Let's discuss evolution from a scientific perspective -not for Creationist, anti-scientific argument

Apparently mice that are taught aversion to a particular smell will pass on that aversion to their offspring, even if the offspring have never encountered the smell themselves and have no reason whatsoever to associate it with fear or aversion, according to this NatGeo article:

Mice Inherit the Fears of their Fathers

Do these experiments point to the possibility that natural selection isn't as random as it's believed to be, at least among the Dawkins-style "Selfish Gene" camp? If newly-acquired knowledge can be encoded directly into DNA and passed on to the next generation, what does that mean about the supposed randomness of genetic mutations?

I'd appreciate hearing from anybody who knows more about the subject of evolutionary biology and especially this interesting subject of possibly directed mutation.

***Please note change in the title. Added this: not for Creationist or other anti-scientific arguments

Please respect thread starters parameter for this debate. - admin

Great so I inherited a fear of vietnamese people and agent orange.

Trolled in the 1st post loool!!! :voodoo:

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Originally Posted by Darkmatters

Do these experiments point to the possibility that natural selection isn't as random as it's believed to be, at least among the Dawkins-style "Selfish Gene" camp? If newly-acquired knowledge can be encoded directly into DNA and passed on to the next generation, what does that mean about the supposed randomness of genetic mutations?

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Natural selection isn't random, the mutations are. But as this article seems to be about epigenetic inheritance, it has nothing to do with mutations of the actual nucleotide sequences. It's a change in either the expression of the gene or the function of the gene instead of the genotype itself.

Epigenetics - Wikipedia, the free encyclopedia
Epigenetic Inheritance - Modern Genetic Analysis - NCBI Bookshelf

Awesome, thanks for responding Blueline. That first article gets way too dense with scientific jargon for me, but I did glean from it and from what you said that epigenetic inheritance isn't a change in DNA that could create a new permanent mutation, so it doesn't affect evolution. Apparently just a few generations inherit the trait, and then I suppose it fades out?

Still it's intriguing that such a trait can be passed on directly at all, rather than through parents teaching the children. I wonder about the possibility of this (epigenetic inheritance) or something similar contributing to actual genetic mutation.

I suppose it's possible that some parts of the DNA is malleable in such a way, that classical conditioning can be transferred onto offspring. It makes a lot of sense, because it would allow very quick adaptation between generations, like say if a certain sound or smell indicated a danger/food/whatever, then the offspring would also instinctively be aware of this.

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Originally Posted by Darkmatters

That first article gets way too dense with scientific jargon for me, but I did glean from it and from what you said that epigenetic inheritance isn't a change in DNA that could create a new permanent mutation, so it doesn't affect evolution.

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I'm not particularly well-versed in epigenetics (it hasn't been a major focus of any of my classes, and I'm about a year away from getting my BSc in biology), but I don't know if it couldn't play a role in evolution by natural selection. Whether a gene is expressed or not, or whether its function is altered, might have some role in how an organism is adapted to its environment. To what extent, I have no idea. But the main point is that epigenetic inheritance does not relate to the nucleotide sequence (the actual base-pairs of the DNA strand - the adenine, cytosine, guanine, and thymine molecules).

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Apparently just a few generations inherit the trait, and then I suppose it fades out?

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I have no idea. Did the original article say this? I didn't read it thoroughly.

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Still it's intriguing that such a trait can be passed on directly at all, rather than through parents teaching the children. I wonder about the possibility of this (epigenetic inheritance) or something similar contributing to actual genetic mutation.

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It is weird, and much cooler than regular old genetics IMO. It reminds me of Lamarckian evolution (where, for example, a giraffe has a long neck because its ancestors would literally stretch their own necks to reach food high in a tree. Evolution doesn't work like that, but with epigenetic inheritance, Lamarckism may not be as wrong as previously thought?). In fact: Lamarckism - Wikipedia, the free encyclopedia

The article did say that 2 generations of mice inherited the smell aversion, but that's all it said on that count. I assumed the trait wouldn't be permanent because, if it was, then wouldn't that constitute a mutation and cause an evolutionary change? I'm still pretty confused about the difference.

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Originally Posted by Darkmatters

I assumed the trait wouldn't be permanent because, if it was, then wouldn't that constitute a mutation and cause an evolutionary change? I'm still pretty confused about the difference.

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Well, a genetic mutation would be changing the actual DNA sequence. An epigenetic modification doesn't affect the DNA sequence. Rather, it affects whether a gene is expressed/turned on, or how much it is expressed, or how the gene functions. This site should be helpful: Epigenetics

If I understand it correctly, epigenetic inheritance works by the addition or removal of certain epigenetic tags that are attached to the DNA and/or histones in response to outside signaling. Histones are proteins that the DNA is wrapped around. They serve two basic purposes: gene expression regulation and space-saving. They help compact the DNA strands so that everything can fit in the nucleus of a cell. But in doing so, they also affect the availability of the genes on the strand to be copied. If they're too compact, they can't be transcribed. This is where the epigenetic tags come in. Each cell type will have a certain epigenetic tag blueprint. One of these tags is a simple methyl group (-CH3), and it seems that DNA that is heavily methylated tends to be transcriptionally inactive. So you can probably understand that changing an epigenetic tag layout may change what kinds of genes are expressed, and in turn change what kinds of proteins a cell will pump out, and what those proteins will go on to do in the body.

You can think of the tags as switches, and the histones as dials. The tags determine whether the gene will be expressed, and the histones determine how much (by changing the physical availability of a gene on the DNA strand).

I think this section of the wiki can answer your question fairly succintly: "These epigenetic changes may last through cell divisions for the duration of the cell's life, and may also last for multiple generations even though they do not involve changes in the underlying DNA sequence of the organism; instead, non-genetic factors cause the organism's genes to behave (or "express themselves") differently."

Ok, that clears things up a lot - especially the last part, thanks for that.

Here's the thing that always kind of bugged me about evolution via natural selection (as a complete layman who's only exposure was to read Dawkins' Mount Improbable and a bunch of Sagan books) -

It just seems to strain credibility that almost any species at all manage to generate viable mutations when environmental conditions threaten their existence.

I mean - how does that work?

Are there constantly mutations happening and the vast majority of them never lead to new species because the environment doesn't necessitate it (not that I'm expecting you to know this Blueline… just conjecturing)? Punctuated equilibrium is a thing, isn't it? Meaning that evolutionary changes generally don't happen for long periods of time, until environmental changes make it necessary to change or die out, and suddenly wham! New species pop up.

It just seems to me (again, as a layman) that it would make sense if somehow the genes are actually responding to environmental pressure. I'm not saying that's definitely what happens - of course nobody knows. But it seems like if evolution really happened only through random mutations that happened to coincide with environmental changes that select in favor of those exact changes - it sort of seems like new species would almost never happen. Or am I sounding like a Creationist? I absolutely don't mean to imply any Creator who's pulling the strings, just to make that clear! Just some hitherto unknown mechanism that causes genes to respond to changing conditions and generate new mutations of specific types. Not because that's what an animal or species WANTS to happen consciously of course - like some species of dinosaur thinking "Wow, wouldn't it be cool if we could grow wings and fly around, and maybe our scales could change into feathers… ". Or "Let's change into banandas". I don't mean to propose any particular mechanism, just saying…

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Originally Posted by Darkmatters

Ok, that clears things up a lot - especially the last part, thanks for that.

Here's the thing that always kind of bugged me about evolution via natural selection (as a complete layman who's only exposure was to read Dawkins' Mount Improbable and a bunch of Sagan books) -

It just seems to strain credibility that almost any species at all manage to generate viable mutations when environmental conditions threaten their existence.

I mean - how does that work?

Are there constantly mutations happening and the vast majority of them never lead to new species because the environment doesn't necessitate it (not that I'm expecting you to know this Blueline… just conjecturing)? Punctuated equilibrium is a thing, isn't it? Meaning that evolutionary changes generally don't happen for long periods of time, until environmental changes make it necessary to change or die out, and suddenly wham! New species pop up.

It just seems to me (again, as a layman) that it would make sense if somehow the genes are actually responding to environmental pressure. I'm not saying that's definitely what happens - of course nobody knows. But it seems like if evolution really happened only through random mutations that happened to coincide with environmental changes that select in favor of those exact changes - it sort of seems like new species would almost never happen. Or am I sounding like a Creationist? I absolutely don't mean to imply any Creator who's pulling the strings, just to make that clear! Just some hitherto unknown mechanism that causes genes to respond to changing conditions and generate new mutations of specific types. Not because that's what an animal or species WANTS to happen consciously of course - like some species of dinosaur thinking "Wow, wouldn't it be cool if we could grow wings and fly around, and maybe our scales could change into feathers… ". Or "Let's change into banandas". I don't mean to propose any particular mechanism, just saying…

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Your post is a little confusing, so I'm not exactly sure what you're asking. But here is quick overview of mutations and natural selection, and a link to a page that describes punctuated equilibrium.

Most mutations are neutral; they neither help nor hurt the organism. Imagine you have a codon in a DNA template that codes for the amino acid alanine, which will then go on to be part of a protein/enzyme. There are four sets of codons that can code for alanine: GCU, GCC, GCA, and GCG. If you have a DNA template that reads CGA, then if the RNA polymerase (which transcribes DNA into mRNA) is working correctly, you will get GCU, which codes for alanine. But if the RNA pol. makes a mistake, it can transcribe CGA incorrectly, perhaps as GCA. But that won't have any effect on the final protein, since GCA also codes for alanine.

Mutations happen all the time, and as I just explained, most are neutral. But whether a mutation is beneficial or deleterious depends on the organism's environment. A mutation that is beneficial for one organism may be harmful to another. Whether a mutation (or group of mutations) is selected for in an environment is where the randomness stops. The mutations are random (i.e we cannot predict them, AFAIK), but their continued existence is not (if they are beneficial).

Punctuated equilibrium: Evolution 101: The Big Issues

I was just basically restating the thread's premise, not asking a question with any straightforward answer. To word it a little differently in hopes some people might join in - I wonder if it's possible that mutations can respond to environmental pressure, rather than just being completely random?

I know that according to the Dawkins-style theory mutations are completely random, but is it a known fact that this is so?

A mutation is just a change in the DNA code, so it doesn't make sense to ask if a mutation can respond to environmental pressure. DNA can be changed by the environment; think of what prolonged and repeated sun exposure can do to skin cells (melanoma). But I don't think DNA can change itself in the context of responding to environmental pressure. That's where epigenetics becomes more relevant, I think.

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Originally Posted by Darkmatters

It just seems to strain credibility that almost any species at all manage to generate viable mutations when environmental conditions threaten their existence.

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This isn't the case. There are a couple of things to clarify.

The first is what Blueline said: evolution doesn't work by organisms generating mutations in times of environmental stress. Rather, they're generating them all of the time. Most of these mutated genes are fairly harmless, and lots of them actually have no effect at all on their carriers because the gene is recessive. So the mutated genes are latent in the population all the time. It's only when the environment changes that selection will occur - but this isn't when the mutation is occurring. For example, chickens still have the genes for teeth, but these genes are ancient. If their environment were to change so that toothed chickens had an advantage, then natural selection would occur and toothed chickens would branch off from the population. But that's not when the mutation occurred, it occurred long ago.

Secondly, evolution doesn't work by "almost all" species adapting their way out of an environmental crisis. Most species who suddenly can't survive in their environment will simply die out. Evolution isn't usually about quickly adapting to survive in new conditions; it's about gradually adapting to benefit from new opportunities (called "niches"). For example: the strain of bacteria which can now metabolise nylon, which did not exist until a few decades ago. The original bacteria species wasn't under threat, but some of those bacteria, after some time, had a mutation which created an enzyme which could metabolise nylon. No other organisms were doing this, so there was a new source of free energy for these bacteria to live off. In this way the mutation spread and a new species was born. This is called "radiative adaptation" because life is radiating outwards into an empty gap. This occurred en masse after the event which killed the dinosaurs. The dinosaurs did not quickly adapt and survive; they all died out. The important thing though was that this left a huge number of niches free. The mammals in particular capitalised on this opportunity, gradually evolving over thousands of years to occupy the niches, which gave us most of the large variation of mammals we see today.

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Originally Posted by Darkmatters

I was just basically restating the thread's premise, not asking a question with any straightforward answer. To word it a little differently in hopes some people might join in - I wonder if it's possible that mutations can respond to environmental pressure, rather than just being completely random?

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Mutations are just chemical events. A random mutagen comes along and collides with a random bit of DNA, changing the base sequence in a random way. Clearly there's nothing "guided" about this process. That's impossible, it would require the DNA to somehow "know" what it coded for, know what the environmental changes were, and come up with a plan to modify itself - and we can see that's just not how the process happens.

These mice experiments are fascinating and ground breaking, although it's early days in terms of whether the results will be vindicated. But what's happening, if it is happening, is not a directed mutation of the DNA. The mutated feature is already there; it's the gene which controls sensitivity to the aroma. This evolved long ago, via blind natural selection. What's happening is a modification the level of expression of this gene, which is called epigenetics. This is not done by the DNA; it's done by various enzymes acting on the DNA. In other words, it's more akin to a feature of the organism - just like the enzymes which control sensitivity to the aroma, or any other kind of gene - than it is to a feature of the DNA. Therefore there's nothing strange about in acting in a "directed", non-random way; it's a feature of the organism, acting in the organism's interests, and like any other feature, it evolved by blind natural selection.

Excellent - thanks for typing all that up Xei. It explains a lot.

I have to read this thread yet - thanks for making it Darkmatters!
But if it's not mentioned already - I read something about this study lately - maybe on neuroskeptic.

The tenor was - yes they found something special - more study will commence.
But no - it does definitively not mean, that a specific fear is directly inheritable.
The hype in the media not being justified because of a, b, c ...

Text from your link, Darkmatters, a bit edited by me to bring out the points which I find esp. interesting:

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Dias trained mice to fear acetophenone over three days, then waited 10 days and allowed the animals to mate. The offspring show an increased startle to acetophenone (with no shock) even though they have never encountered the smell before. And their reaction is specific: They do not startle to a different odor.

The scientists also looked at the F1 and F2 animals’ brains. When the grandparent generation is trained to fear acetophenone, the F1 and F2 generations have more “M71 neurons” in their noses, Dias said. These cells contain a receptor that detects acetophenone. Their brains also have larger “M71 glomeruli,” a region of the olfactory bulb that responds to this smell.

”What is striking is that the neuroanatomical results still persist after IVF (in vitro fertilization),” Dias said. “There’s something in the sperm.”

“Do you have any idea of how this information being stored in the brain is being transmitted to the gonads?” a questioner asked.
The short answer is that the researchers don’t have any idea, though they’ve thought about several possible explanations.

Apparently a study in cats and pigeons showed that after smelling an odor, the odorant receptor molecules can get into the blood stream, and other studies have reported odorant receptors on sperm. So maybe the odor molecules get into the bloodstream and make their way to sperm.

Another possibility is that microRNAs — tiny RNA molecules involved in gene expression — get into the bloodstream and deliver odor information to sperm.

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Fascinating stuff - so they consider free receptors in the bloodstream reaching the gonads and being taken on board by sperm as a mechanism besides classical epigenetics, too!

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Originally Posted by Darkmatters

Apparently just a few generations inherit the trait, and then I suppose it fades out?

Still it's intriguing that such a trait can be passed on directly at all, rather than through parents teaching the children. I wonder about the possibility of this (epigenetic inheritance) or something similar contributing to actual genetic mutation.

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The first one is a good and probably not yet answerable question.
As to the second one - it is not fear, what the offspring inherit - they inherit having more olfactory receptors in the nose and a bigger brain-region, which belongs to these receptors and their detective work on acetophenone. And they react with startle when exposed to it.
How the neuroanatomic features in the offspring correlate with this reaction - behaviour - is not clear, as far as I understand it.

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Originally Posted by BLUELINE976

I'm not particularly well-versed in epigenetics (it hasn't been a major focus of any of my classes, and I'm about a year away from getting my BSc in biology), but I don't know if it couldn't play a role in evolution by natural selection. Whether a gene is expressed or not, or whether its function is altered, might have some role in how an organism is adapted to its environment. To what extent, I have no idea. But the main point is that epigenetic inheritance does not relate to the nucleotide sequence (the actual base-pairs of the DNA strand - the adenine, cytosine, guanine, and thymine molecules).

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I also believe, there is some way, in which epigenetic happenings will enter into the hard code. We lack understanding of these processes, though, as far as I know.

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Originally Posted by BLUELINE976

It is weird, and much cooler than regular old genetics IMO. It reminds me of Lamarckian evolution (where, for example, a giraffe has a long neck because its ancestors would literally stretch their own necks to reach food high in a tree. Evolution doesn't work like that, but with epigenetic inheritance, Lamarckism may not be as wrong as previously thought?). In fact: Lamarckism - Wikipedia, the free encyclopedia

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Yes. The environment, inner workings of the mind and actual behaviour change at least neuroanatomy without a doubt. Since these mice startle, and are not just only more sensitive to registering the stuff olfactorily - there must be more than just a lowered detection threshold, I guess.
Or are there so many receptors then, that smelling some of the stuff leads to startle because of unusually intense olfactory sensations in general?
Since olfactory information is so crucial to detect danger and avoid it, maybe it's just enough to have a really unusual intensity of any smell to generate startle? Startle is not avoidance after all - only a raise in directed attention. But then - the olfactory bulbs, they talk about here, are in contrast to other sensory processing brain-areas literally and directly a part of the famous, emotion generating limbic system. So maybe an emotional content, or at least a negative association, could lie directly in the bulbs, where they did find modifications, see above. Fascinating! Very!!

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Originally Posted by Darkmatters

The article did say that 2 generations of mice inherited the smell aversion, but that's all it said on that count. I assumed the trait wouldn't be permanent because, if it was, then wouldn't that constitute a mutation and cause an evolutionary change? I'm still pretty confused about the difference.

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Originally Posted by Darkmatters

Here's the thing that always kind of bugged me about evolution via natural selection (as a complete layman who's only exposure was to read Dawkins' Mount Improbable and a bunch of Sagan books) -

It just seems to strain credibility that almost any species at all manage to generate viable mutations when environmental conditions threaten their existence.

I mean - how does that work?

It just seems to me (again, as a layman) that it would make sense if somehow the genes are actually responding to environmental pressure. I'm not saying that's definitely what happens - of course nobody knows. But it seems like if evolution really happened only through random mutations that happened to coincide with environmental changes that select in favor of those exact changes - it sort of seems like new species would almost never happen. Or am I sounding like a Creationist? I absolutely don't mean to imply any Creator who's pulling the strings, just to make that clear! Just some hitherto unknown mechanism that causes genes to respond to changing conditions and generate new mutations of specific types. Not because that's what an animal or species WANTS to happen consciously of course - like some species of dinosaur thinking "Wow, wouldn't it be cool if we could grow wings and fly around, and maybe our scales could change into feathers… ". Or "Let's change into banandas". I don't mean to propose any particular mechanism, just saying…

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Originally Posted by Darkmatters

I was just basically restating the thread's premise, not asking a question with any straightforward answer. To word it a little differently in hopes some people might join in - I wonder if it's possible that mutations can respond to environmental pressure, rather than just being completely random?

I know that according to the Dawkins-style theory mutations are completely random, but is it a known fact that this is so?

Are there constantly mutations happening and the vast majority of them never lead to new species because the environment doesn't necessitate it (not that I'm expecting you to know this Blueline… just conjecturing)? Punctuated equilibrium is a thing, isn't it? Meaning that evolutionary changes generally don't happen for long periods of time, until environmental changes make it necessary to change or die out, and suddenly wham! New species pop up.

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I have some sweet material at hand, from collectively taking this thread: http://www.dreamviews.com/religion-s...ns-here-6.html on the path of evolution for the time being.
It could be helpful - your missing link might be "decent with modification":

http://38.media.tumblr.com/8e65ae4b1...66ao3_1280.jpg


And seriously - the following video, courtesy UM, is not only super-sweet and hilarious - it is great concerning the information being presented - clear and concise, a broad and quite comprehensive overview on the basics.
I think, you might find suitable explanations for some of your questions:

http://www.youtube.com/watch?v=hOfRN0KihOU

Thanks Steph, all of that is very helpful!

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Originally Posted by StephL

I also believe, there is some way, in which epigenetic happenings will enter into the hard code. We lack understanding of these processes, though, as far as I know.

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See, now this stuff is fascinating to think about!

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Originally Posted by Xei

evolution doesn't work by organisms generating mutations in times of environmental stress. Rather, they're generating them all of the time. Most of these mutated genes are fairly harmless, and lots of them actually have no effect at all on their carriers because the gene is recessive. So the mutated genes are latent in the population all the time. It's only when the environment changes that selection will occur - but this isn't when the mutation is occurring. For example, chickens still have the genes for teeth, but these genes are ancient. If their environment were to change so that toothed chickens had an advantage, then natural selection would occur and toothed chickens would branch off from the population. But that's not when the mutation occurred, it occurred long ago.

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This idea is very intriguing. So if I understand correctly, there are a lot of these old recessive mutations stored in the DNA, and if one of them becomes useful in a changing environment it can or will 'take effect'? I don't know the terminology. I'm curious about how long it would take for instance for toothed chickens to develop if it became necessary useful. Several generations? One? Dozens? Does this mean for instance that modern humans might have recessive genes for thick body hair, or for feet that look like hands, with opposable 'thumbs' (yeah, like in AeonFlux, or the Beast)? And that in the right environmental circumstances these traits could become 'reactivated'?

And when this happens - when these recessive traits become reactivated, that's not called evolving? I'm getting the sense that it isn't evolution unless it changes the DNA, and/or maybe creates a distinct new species?

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Originally Posted by Darkmatters

This idea is very intriguing. So if I understand correctly, there are a lot of these old recessive mutations stored in the DNA, and if one of them becomes useful in a changing environment it can or will 'take effect'? I don't know the terminology. I'm curious about how long it would take for instance for toothed chickens to develop if it became necessary useful. Several generations? One? Dozens? Does this mean for instance that modern humans might have recessive genes for thick body hair, or for feet that look like hands, with opposable 'thumbs' (yeah, like in AeonFlux, or the Beast)? And that in the right environmental circumstances these traits could become 'reactivated'?

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I can't answer this specifically out of thin air - but I might get back to you on it.
I needed to do some reading up first - my university studies were a long time ago.
But what is maybe also interesting to know here, is that while we develop after conception and into a complete birth-rife baby - we undergo what is called ontogeny or morphogenesis. And the funny thing is, that we develop our final shape by taking the "evolutionary route" - which is called phylogenetics.

So that means, that an embryo starts out with gills for example - and that is not for breathing in the uterus. Otherwise we needed them until birth. An embryo gets oxygen directly from the mother's blood, only after birth do the lungs unfold and breathing starts.
But first come gills, which then develop away into other structures.
So some of these silent genes are not even always silent - they come to expression in the womb, and then get deactivated again.

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Originally Posted by Darkmatters

And when this happens - when these recessive traits become reactivated, that's not called evolving? I'm getting the sense that it isn't evolution unless it changes the DNA, and/or maybe creates a distinct new species?

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I can tell you, how evolution is currently defined: Changes in allelic frequency.
If we map the different forms of genes (alleles) of a population and after a few generations, the frequency changes - evolution has occured.
Allele frequency - Wikipedia, the free encyclopedia
That still doesn't answer your question completely, though.


But I can tell you something, which you might find fascinating.
In case of malignant tumours - it can happen that all sorts of genes get "mis-activated" and in places, where they do not belong at times.
Gene expression is regulated not only to switch on "human" so to speak - but you need to activate exactly the correct genes for a certain sort of adult cell in the organs. Every cell has all of the organism's genetic information - but you do not want teeth in the brain for example, or hair.
But exactly this can happen, and among freaky illnesses - this tumour is a star: the 'Craniopharyngeoma'. It develops from "omnipotent" embryonic stem cells in the pituitary gland. Mainly in children - and yupp - a brain-tumour with teeth and hair and other features in it results:

http://upload.wikimedia.org/wikipedi...aryngioma1.jpg
The stuff in the middle is not supposed to be there.

One thing though - your offspring cannot inherit your body-cell tumour - neither this one from embryonic stem cells.
Only what is in the gametes (eggs and sperm) can be passed down - not what is somewhere else.
Now men produce fresh sperm all the time - while females make their eggs once and for all while they are still in the womb. The eggs get released one at a time (well or two = non-identical twins etc.) during her fertility phase, however I should call it in English..?

That is also why it is genetically dangerous to get a child late in life as a woman, while age does not - or by far not so much - matter in men.
While time goes by - more and more mutations, brought about by chance or environment, will heap up in these eggs with their half set of chromosomes. Meaning mistakes and even disastrous mistakes are more likely to occur - mainly spontaneous early abort.
A famous other example is Down-syndrome = Trisomy 21. What happens here, is that children end up with one chromosome 21 too many -
a chromosomal aberration as opposed to a point-mutation, which happens on the level of genes with their base-pairs.

To make sure, I do not come over as doing something like vaccination-scaremongering here with maternal age, despite me really knowing this -
I'll spoiler you the respective part from Wikipedia:

Spoiler for Trisomy 21 prevalence/risks with maternal age:

Maternal age affects the chances of having a pregnancy with Down syndrome.[89] At age 20 the chance is 1 in 1441; at age 30 it is 1 in 959; at age 40 it is 1 in 84; and at age 50 it is 1 in 44.[89] Although the probability increases with maternal age, 70% of children with Down syndrome are born to women 35 years of age and younger, reflecting the fact that younger people have more children.[89] The father's older age is also a risk factor in women older than 35 but not in women younger than 35, and may partly explain the increase in risk as women age.[92]

Menopause comes very late in some women - even in their 60s, or in freak cases even later. I believe to remember a 70 year old giving birth in India a while ago, but with taking oral hormones - resulting in 6-fold "twins", all healthy, but it's madness and irresponsible in my eyes.

Buut - evolution can occur like this as well - a point-mutation, or a whole bunch of them in the gametes, can of course result in an unusual genotype (the overall genetic make-up), and as a result an unusual phenotype (the actual shape of an organism) in the offspring. And that organism might be something special in a positive way!

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Originally Posted by Darkmatters

This idea is very intriguing. So if I understand correctly, there are a lot of these old recessive mutations stored in the DNA, and if one of them becomes useful in a changing environment it can or will 'take effect'?

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I think the key thing to point out in order to answer your question is that there are always a small number of mutants in the population. It's not a matter of the mutation only becoming "active" when the environment changes. There are probably a few chickens with teeth living right now, and there always are. It's just that currently, that's not advantageous, so those particular chickens don't produce as many children and the mutation doesn't spread... it just keeps appearing sporadically at the same rate. But if the environment were to change, then they would have more progeny relative to their peers, and so the mutation would quickly spread throughout the whole population. Another random example is people with "werewolf syndrome" whose faces are covered in fur. Let's say for the sake of illustration that this is caused by a recessive mutated gene. So, there always a small number of people with one copy of the gene, but it doesn't affect them, so they reproduce at the normal rate and the gene stays in the population. But in the rare case that two people with the gene procreate and produce a child with two copies of the gene, that child will have the condition. So a very small number of these people always exists in the population. Normally they don't have as many children and so the werewolf feature dies away. But say we suddenly found ourselves in another ice age. Those people might be compensated by the extra warmth to such a degree that they survived more than other people and thus had more offspring; and therefore werewolf syndrome will clearly spread through the population.

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And when this happens - when these recessive traits become reactivated, that's not called evolving? I'm getting the sense that it isn't evolution unless it changes the DNA, and/or maybe creates a distinct new species?

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This is just a semantic issue, really. Evolution is more of a topic than a strictly defined scientific event. It's defined as "inherited change in generations of organisms over time", which is quite general and vague. A mutation spreading throughout the population due to, for example, a change in the environment, is evolution "en masse" because it's a general change to a whole population of organisms. A single chicken being born with an unusual (but unoriginal) trait... you could say is evolution on the scale of single organisms. The fact that it's not a new mutation doesn't rule it out as evolution... there was no new mutation in the "en masse" example either, it was just an old mutation changing its prevalence, but that's definitely evolution. Evolution doesn't even have to be "directed"; sometimes a variation of a gene dies out just by random, not because it was inferior (a process called "genetic drift").

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Originally Posted by Xei

I think the key thing to point out in order to answer your question is that there are always a small number of mutants in the population. It's not a matter of the mutation only becoming "active" when the environment changes. There are probably a few chickens with teeth living right now, and there always are. It's just that currently, that's not advantageous, so those particular chickens don't produce as many children and the mutation doesn't spread... it just keeps appearing sporadically at the same rate. But if the environment were to change, then they would have more progeny relative to their peers, and so the mutation would quickly spread throughout the whole population. Another random example is people with "werewolf syndrome" whose faces are covered in fur. Let's say for the sake of illustration that this is caused by a recessive mutated gene. So, there always a small number of people with one copy of the gene, but it doesn't affect them, so they reproduce at the normal rate and the gene stays in the population. But in the rare case that two people with the gene procreate and produce a child with two copies of the gene, that child will have the condition. So a very small number of these people always exists in the population. Normally they don't have as many children and so the werewolf feature dies away. But say we suddenly found ourselves in another ice age. Those people might be compensated by the extra warmth to such a degree that they survived more than other people and thus had more offspring; and therefore werewolf syndrome will clearly spread through the population.

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This is what I termed 'descent with modification'.

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Originally Posted by Xei

This is just a semantic issue, really. Evolution is more of a topic than a strictly defined scientific event. It's defined as "inherited change in generations of organisms over time", which is quite general and vague. A mutation spreading throughout the population due to, for example, a change in the environment, is evolution "en masse" because it's a general change to a whole population of organisms. A single chicken being born with an unusual (but unoriginal) trait... you could say is evolution on the scale of single organisms. The fact that it's not a new mutation doesn't rule it out as evolution... there was no new mutation in the "en masse" example either, it was just an old mutation changing its prevalence, but that's definitely evolution. Evolution doesn't even have to be "directed"; sometimes a variation of a gene dies out just by random, not because it was inferior (a process called "genetic drift").

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It can be said a bit more specifically, as I did above - the key term is: 'changes in allelic frequency'.

"If we map the different forms of genes (alleles) of a population and after a few generations, the frequency changes - evolution has occurred.
This definition is is the best description to date that captures the ever-changing living world."

I quote from the rest of the info-graphic which is not here.

Yeah, that's a good definition for these purposes.

What I meant when I said that "evolution" was more of a broad conceptual structure than a single process is, for example, that "evolution" also refers to the fact that any two species has a common ancestor, and that thus we're all on the same tree of life - which is a distinct concept from changes in allele frequency.

Going back to the original question for a moment, elaborating on what I said about epigenetics being more akin to a feature of the organism than a feature of its DNA: it may also help to think in the following terms. We're already okay with the idea that a mouse may have a mutation which makes it averse to, for instance, cyanide. This is a helpful feature for whichever mouse has it, so by natural selection it becomes prevalent. The feature in the article is not so very different. The difference is that it's more like a "meta feature"; it's a feature which benefits the next several generations, rather than the first mouse to receive it. It doesn't do anything for the first mouse... but if that mouse learns to be averse to a certain chemical, its progeny will be also. So this "meta-feature" of the next few generations of mice (rather than a feature of one mouse) is positively selected for over time. The reason we find it weird is that the specific physical mechanism which this feature uses to transmit the information is closely linked to the genetic material itself. Of course, the genetic material is also what codes for the meta-feature in the first place, so we have something of a confusion of levels. It's easier to understand if you pretend that the meta-feature used some different physical mechanism... for instance, if the mutation instead caused the first mouse to constantly sing "don't eat chemical X" for the rest of its life, including to its children. Or perhaps if it caused the first mouse to feed its babies special food which somehow increased the expression of the "don't eat chemical X" genes in its babies. This we're okay with; it's just a weird case of natural selection. What's really happening is analogous, but the message isn't being transmitted via song or via special food: it's being transmitted via chemical processes acting on the chromosomes.

Hi there!

I don't know if it comes to the discussion here and if you already know it, but some time ago I was discussing with my brother about evolutionism and he showed me the following documentary that let me thinking about the complexity of mutations and natural selection:

https://www.youtube.com/watch?v=VekUf325SHM

I think it's something to take into account too, when talking about the subject of evolution.

There's no such thing as "evolutionism" any more than there is such a thing as "gravityism". Evolution is an observed fact with mountains of evidence, some nice descriptions of which you can find here:

Evidence of common descent - Wikipedia, the free encyclopedia

With respects to "irreducible complexity", no instance of irreducible complexity has ever been found in nature. A classic example of claimed "irreducible complexity" was the flagellum of a bacteria, which requires many separate parts to function. But this was disproven: in fact, there are bacteria in nature which only have around half of the parts required for a flagellum, but they use it for a completely different purpose; for injecting toxins. You can read about that here:

Irreducible complexity - Wikipedia, the free encyclopedia

Another common claimed example is the eye, but you only need to actually look at the animal kingdom to discover many sequential steps in complexity. You can read about that here:

Evolution of the eye - Wikipedia, the free encyclopedia

And there's a cool video here:

https://www.youtube.com/watch?v=7jEhzAn1hDc

I recommend you also show all of this information to your brother.

^^Actually I showed him other videos including one I saw in one of the @StephL's threads to answer my brother's comment. I liked the eye one you posted there because it was something I was looking for to understand the disposal of the photo sensors inside of it although that's not the subject of this thread.

What is still unclear to me is the random origin of the DNA instructions sequence, which I can only argument that possibly life didn't start on earth.

Hach Xei!

Attachment 7266

I suppose I have to add that I sigh purely platonically here - despite that congratulation joke...:wink:
This might be termed mathematician-ophilia - I married mine already and my best female friend is one, too!

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Originally Posted by Xei

Yeah, that's a good definition for these purposes.

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:thanks:

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What I meant when I said that "evolution" was more of a broad conceptual structure than a single process is, for example, that "evolution" also refers to the fact that any two species has a common ancestor, and that thus we're all on the same tree of life - which is a distinct concept from changes in allele frequency.

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Yes - there is not only the frequency aspect - 'common ancestry' or 'tree of life' stands for a very crucial concept.
Life needed only to come into existence once for evolution to occur.
And "meta-features" is an apt description of the sphere of epigenetic influences!

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The reason we find it weird is that the specific physical mechanism which this feature uses to transmit the information is closely linked to the genetic material itself. Of course, the genetic material is also what codes for the meta-feature in the first place, so we have something of a confusion of levels. It's easier to understand if you pretend that the meta-feature used some different physical mechanism...

for instance, if the mutation instead caused the first mouse to constantly sing "don't eat chemical X" for the rest of its life, including to its children. Or perhaps if it caused the first mouse to feed its babies special food which somehow increased the expression of the "don't eat chemical X" genes in its babies.

This we're okay with; it's just a weird case of natural selection. What's really happening is analogous, but the message isn't being transmitted via song or via special food: it's being transmitted via chemical processes acting on the chromosomes.

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Such lovely metaphors for our meta-featured mouse!

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Originally Posted by Xei

There's no such thing as "evolutionism" any more than there is such a thing as "gravityism". Evolution is an observed fact with mountains of evidence, some nice descriptions of which you can find here:

Evidence of common descent - Wikipedia, the free encyclopedia

With respects to "irreducible complexity", no instance of irreducible complexity has ever been found in nature. A classic example of claimed "irreducible complexity" was the flagellum of a bacteria, which requires many separate parts to function. But this was disproven: in fact, there are bacteria in nature which only have around half of the parts required for a flagellum, but they use it for a completely different purpose; for injecting toxins. You can read about that here:

Irreducible complexity - Wikipedia, the free encyclopedia

Another common claimed example is the eye, but you only need to actually look at the animal kingdom to discover many sequential steps in complexity. You can read about that here:

Evolution of the eye - Wikipedia, the free encyclopedia

And there's a cool video here:

https://www.youtube.com/watch?v=7jEhzAn1hDc

I recommend you also show all of this information to your brother.

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Ha!
Xei - this is a superb little gem on the eye!
Dawkins talking, I believe?
For who is too lame to click and find it's only two minutes of easily digestible and convincing "explanations with pictures" - here you go:

https://www.youtube.com/watch?v=7jEhzAn1hDc

An afterthought: the eye has evolved separately and independently several times in life's history on earth - insects with facet-eyes, our camera-eyes - and I forgot the others, but I will look it up eventually (octopuses have very special camera eyes - I should look that up as well).
'Evolutionary conversion' is the concept here - quite rare - but it makes you speculate how similar alien beings could be to local lifeforms. Could it even be that they have DNA like ours - maybe even in the sense of common ancestry? It could in such a case also be convergence, though. Maybe DNA or something very similar is simply the best carrier for this sort of code, which can be made with the atoms on offer?

As an example for using very different concepts for a common purpose: clocks. You can use a pendulum or a spring and some human help, or use the sun or water - build an atomic clock and more. Not to forget the biological clocks!

One level up from the basic code - what sort of eyes will they have, if we finally met somebody? Would they use the same concepts?
But one thing is for sure - if we finally met aliens - almost everybody would look back at us! :wink:

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Originally Posted by Box77

^^Actually I showed him other videos including one I saw in one of the @StephL's threads to answer my brother's comment. I liked the eye one you posted there because it was something I was looking for to understand the disposal of the photo sensors inside of it although that's not the subject of this thread.

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Just saw that. For once I feel flattered that you use my threads in order to inform yourself!

Attachment 7267

As said above - it could be that life on earth is "imported" - for example by meteor impacts.
But then it had to have come into existence somewhere else.
Why should anything be different there?
Besides the fact, that we begin to understand, how life works around hydrothermal vents in the deep sea.
Life without oxygen - using the heat and local chemicals for energy production.
And pores in stone could have played a role in separating mere so called "hyper-cycles" into a unity with membrane.
These cycles being free reactions among nucleotide acids alone or in combination with amino acids - featuring self-replication.
This is one hypothetical mechanism for the origin of life on earth.

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Originally Posted by Box77

What is still unclear to me is the random origin of the ADN instructions sequence, which I can only argument that possibly life didn't start on earth.

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Could you please expound on this - are you talking about 'The Game'?

Ah crap!! It's too late for me to edit the original post and add "NO CREATIONIST ARGUMENTS!!" I never intended for this thread to descend into that mess - that's already what the majority of 'discussions' about evolution are on this site, no need for more of that obstructionist claptrap to clog up the actual discussion! Maybe I can get a mod to edit it. Sorry Box77 - I don't know if that's where you're coming from or not - the instant I saw the non-word Evolutionism the red lights and sirens started going off, but then you seem to be conversant with the science of evolution to some extent, so I'm not sure where you stand.

Steph, yes, I am familiar with the way embryos seem to cycle through the stages of evolution, beginning as a single cell in a liquid environment, then emerging to begin breathing air and crawl on all 4s until they can rise to 2 legs (and like you said of course, gills etc). I ran across that in a Sagan book somewhere. It serves as a very literal illustration of the way evolution progressed, by only adding new systems onto existing ones and deactivating older unneeded ones while leaving the mechanisms in place. It's why the brain is built in layers like an onion, around a core called the lizard brain surrounded by the limbic system or mammal brain with all the warm fuzzy emotions and altruism, followed finally by the neocortex or human brain, seat of abstract thinking and more advanced consciousness. Evolution can't remove old unneeded systems, it can only build on top of them and switch the genes for the old systems off when they're no longer needed. Sort of the way you see modern cities built over old ruins of stone buildings.

The main difference I can see between your description of what evolution is and Xei's is that I can understand his! :cheeky: So, alleles is just another word for genes? Sheesh! If they mean genes, why don't they just SAY genes?! Scientists - making their ideas incomprehensible to the rest of the world for hundreds of years… :lol:

Xei - you know I knew some of this, but it just didn't click together completely until you said this, about the 'werewolf mutation' or whatever it's called. Of course!! Side show freaks etc.. yes, mutants do walk among us, it's not just at Xeivier's School For Gifted Youngsters! And I have heard about people growing tumors or lumps filled with teeth and hair etc… nasty stuff! In fact I went up and had lunch right after reading this and almost gagged a couple of times, so thanks for that! :hurl: But it's all in the name of science, so I can deal. So yeah, obviously then if an old recessive gene or trait or whatever becomes activated, it takes effect immediately and completely in the offspring. Wicked! I assume that's contingent on the trait being compatible - I mean, something far removed in evolutionary timescale like scales or fins wouldn't be able to develop on a human, right? Or would it? Maybe some kind of "mermaid mutation"? I've laughed myself hoarse a few times over commercials for that mermaid show that purports to show real evidence and footage of living mermaids, but maybe there actually could be some form of human with scales or fins (though highly doubtful it would incorporate a human torso and head with a fish tail… :chuckle: )

Hey, I Just realized - there are people with webbed fingers and toes - not exactly fins, but close! So maybe an Oswald Cobblepot (the Penguin from Batman Returns) could be a possibility, or something similar, after all. (LOL ok, never mind - he was a freakin' PENGUIN - not a fish!! Not one of our ancestors.. )

Just wanted to bump this to the top, because the title has been changed at my request. Hopefully everybody can still find it. But I guess it will still show up as a subbed thread or somebody quoting you even with the new title. Anybody approaching this from a Creationist or other non-scientific perspective - feel free to discuss evolution, but not to argue against it. There are countless other threads for that already, and all the arguments have been heard ad infinitum anyway. On this thread we ask questions of those who have studied the science of evolutionary biology - we don't tell them they're wrong.

@Darkmatters: I didn't have the time yet to read the whole thread (I will as soon as I can, because of I think it's relevant to my interest). I was just wondering if all the variables were taking into account. I don't consider myself on the creationist side (:chuckle: Thank god!) I understand some people tend to believe in creators when they cannot explain the origins of something. I don't want to argue about imaginary variables. I have my point about the "imaginary" part on the complex numbers but it's the subject of another discussion. Although if we are talking about nature, I think it must be considered the imaginary unit, which satisfies the equation i^2 = −1; because of I think we could be the expression of that.

I found the title of your thread interesting, including the corrected one, because of two things I recently read about:

1. The apparently fact that it's possible to erase memories and restore them by using pulses of light. How scientists used a virus to deliver a gene to some neurons in order to produce a series of light-responsive proteins, etc.

2. The apparently fact that it was found vitamin B3 in a group of eight ancient, carbon-rich meteorites, and the possibility that it was generated out of earth, etc.

I was studying something about proteins, enzymes, vitamins, etc. And it called my attention the structure of all these sort of molecules, including DNA, which I cannot find random at all. And I wondered, under a scientific field, if life could have been originated out of earth, or at least its basic components more than just the chemical elements but the complex molecules.

Your thread called my attention because of as usual, I tend to project these sort of concepts back in time looking for the moment when it started, and once again I found myself floating in some quantum state where I couldn't collapse the system into something I can understand.

By the way, I saw that video I posted with the intention to understand their point of view and I found some pretty interesting things there which I think could be missing on this thread. But as I said, I don't know, I have to read the whole thing first.

That's all, thanks for reading.

Awesome - glad to hear you're coming at this from a scientific viewpoint. Part of what you're talking about - the origin of life - is really outside of the field of evolution though, since evolution is only about the progression of life, not how it got started.

Do you have links to those articles? It would be a lot better to read the articles rather than just a vague description of what they're about. I'd like to see them, they do sound intriguing.

Sorry, I forgot to mention the articles:

1. A New Technique Could Erase Painful Memories -- Or Bring Them Back

2. Meteors May Have Brought Vitamin B To Earth | Popular Science

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Originally Posted by Darkmatters

Steph, yes, I am familiar with the way embryos seem to cycle through the stages of evolution, beginning as a single cell in a liquid environment, then emerging to begin breathing air and crawl on all 4s until they can rise to 2 legs (and like you said of course, gills etc). I ran across that in a Sagan book somewhere. It serves as a very literal illustration of the way evolution progressed, by only adding new systems onto existing ones and deactivating older unneeded ones while leaving the mechanisms in place. It's why the brain is built in layers like an onion, around a core called the lizard brain surrounded by the limbic system or mammal brain with all the warm fuzzy emotions and altruism, followed finally by the neocortex or human brain, seat of abstract thinking and more advanced consciousness. Evolution can't remove old unneeded systems, it can only build on top of them and switch the genes for the old systems off when they're no longer needed. Sort of the way you see modern cities built over old ruins of stone buildings.

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Yes - you could see it like this - but in the case of "the reptile brain" or "basic mammal brain" - it's not so, that these are the shabby old stuff.
They work beautifully well - and we wouldn't get overly far without them, too.
No fear, aggression, sexual desires - no love and compassion-base - not even Spok would get anywhere!

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Originally Posted by Darkmatters

The main difference I can see between your description of what evolution is and Xei's is that I can understand his! :cheeky: So, alleles is just another word for genes? Sheesh! If they mean genes, why don't they just SAY genes?! Scientists - making their ideas incomprehensible to the rest of the world for hundreds of years… :lol:

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Pööh! Attachment 7270

Well I found my little picture on 'descent with modification' also nice - only with rabbits and carrots, and without explaining why the light grey ones are better carrot munchers - but anyway!

And this is what I wrote on 'allelic frequency':

"If we map the different forms of genes (alleles) of a population and after a few generations, the frequency changes - evolution has occurred." There is a slight semantic difference - none our business here, though.

But you are right of course - hence my platonic sighing at maestro Xei.
This can't even hope to beat werewolves feeling nice in the next ice age and singing mice! I stand humbled! :wink:

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Originally Posted by Darkmatters

Xei ... - And I have heard about people growing tumors or lumps filled with teeth and hair etc… nasty stuff! In fact I went up and had lunch right after reading this and almost gagged a couple of times, so thanks for that! :hurl: But it's all in the name of science, so I can deal.

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Aand - another pöööh! That was "my tumour" which made you gag!! Attachment 7270

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Originally Posted by Darkmatters

So yeah, obviously then if an old recessive gene or trait or whatever becomes activated, it takes effect immediately and completely in the offspring. Wicked! I assume that's contingent on the trait being compatible - I mean, something far removed in evolutionary timescale like scales or fins wouldn't be able to develop on a human, right? Or would it? Maybe some kind of "mermaid mutation"? I've laughed myself hoarse a few times over commercials for that mermaid show that purports to show real evidence and footage of living mermaids, but maybe there actually could be some form of human with scales or fins (though highly doubtful it would incorporate a human torso and head with a fish tail… :chuckle: )

Hey, I Just realized - there are people with webbed fingers and toes - not exactly fins, but close! So maybe an Oswald Cobblepot (the Penguin from Batman Returns) could be a possibility, or something similar, after all. (LOL ok, never mind - he was a freakin' PENGUIN - not a fish!! Not one of our ancestors.. )

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It is probably not so, that all and everything, which is in the human genome, can come to expression suddenly just like that. But remember the gills - you and me, we had them expressed already. What about more freaky stuff showing up in the final phenotype (the shape of an organism)?
As you found yourself - webbing is easy.
But once you have something rather extreme, you are quite likely going to end up as a tiny little blob of "blood" in sanitary trash after a very early spontaneous abort - completely unnoticed by the world. Gagging already? Attachment 7270

Another thing - we have a lot of so called "junk-DNA" - non-coding bits, which seem to be good for nothing. They could well come in for evolutionary purposes. When I studied, junk-DNA was just a riddle - but I believe nowadays we understand more about it..?

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Originally Posted by Box77

1. The apparently fact that it's possible to erase memories and restore them by using pulses of light. How scientists used a virus to deliver a gene to some neurons in order to produce a series of light-responsive proteins, etc.

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It is meanwhile possible to erase traumatic memories with drugs given at crucial points in time. But I guess, what you are getting at is completely different. I do not know, what you could mean and agree with Darkmatters - a link would be fine!

Edit: I saw your two links just now - thank you - will get back to you at a later point!

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Originally Posted by Box77

2. The apparently fact that it was found vitamin B3 in a group of eight ancient, carbon-rich meteorites, and the possibility that it was generated out of earth, etc.

I was studying something about proteins, enzymes, vitamins, etc. And it called my attention the structure of all these sort of molecules, including ADN, which I cannot find random at all. And I wondered, under a scientific field, if life could have been originated out of earth, or at least its basic components more than just the chemical elements but the complex molecules.

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Yeah - but what does this tell you? I know, we found an organic* macromolecule somewhere.
Thing is - bigger organic molecules would only be the basis for further steps towards life, such as the hypothetical hyper-cycles I mentioned.
It is easier to propose, that such molecules could have come into being a myriad times all over the cosmos, than actual life.
So it might mean, that where that came from is life - or it means there are just carbon based molecules.
And even if there was life which "made" this vitamin B - it would still not follow, that we share a common ancestry.

One also has to take into account, that any life will probably be carbon-based - simply because of carbon's traits as an atom.
Silicate could also work - but not much else. And silicate is less likely for reasons, I can't pull out of my nose right now.
If there is oxygen and hydrogen, including in the form of liquid water, carbon, nitrogen, some sulphur and phosphate - and some extra energy from volcanism, or impacts, or cosmic radiation, or something - these molecules can form.
What would actually be suspicious on account of common ancestry, would be finding actual DNA or RNA identical to ours or very similar in life from outer space. But it's all science fiction up to now, idle speculation.

Of course these molecules are not random - atoms follow their structure and chemical attributes concerning with what they go into binding. Certain molecules are bound to happen, just simply because of how chemistry works.
I'm not saying, we would know all and everything about how organic* macromolecules form spontaneously, though.

Could you explain to me, what you mean with "ADN" please?

* "Organic" only denominates the structure of these molecules - namely (often complex) hydro-carbons.
It does not mean, that such a molecule was necessarily once "made" by an organism.

But they are out there! I want to and do quite firmly believe!!

:alien:

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Originally Posted by StephL

Could you explain to me, what you mean with "ADN" please?

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DNA!!!!! :rolllaugh: Sorry, once again my language neural connections are playing those tricks on me... :D (Already fixed it, thanks!)

Edit: More than an answer, some questions

Finally I reviewed the whole thread and some intrigues came up to my mind along the way:

Am I wrong or during the gene transmission from one generation to another, it is the male progenitor who has the major chances to 'inject' new memory-based information into his DNA sequence because of its always producing new gametes rather than the females who have all of her gametes somehow already there? Perhaps that would be the reason why female gametes would get kind of age-worn?

Some time ago I was fascinated with the phenomena that occurred with the Brine Flies (Short video here: Alien Empire III - Brine flies. - YouTube) and I thought it was evolution taking place already. Although after some discussion it was told that what is happening there is just the adaptation of a species into an environmental change. I got confused by the concepts, but isn't it that adaptation is the first step towards the evolution of a species? I would like to hear a more detailed explanation about what is exactly happening there. I think there could be very useful information about insect evolution here.

I don't think that the origin of life is completely outside of its progression because of the first generations after its start, wouldn't it be somehow the first steps of its evolution?

Another thank you to Darkmatters for this thread - I had such an itch in my fingers to finally get somewhere in the creationist debate next door.
And it simply does not seem to happen! :shakehead2:
But this here is much better in terms of entertainment and educationary experiences anyway!!

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Originally Posted by Box77

Am I wrong or during the gene transmission from one generation to another, it is the male progenitor who has the major chances to 'inject' new memory-based information into his DNA sequence because of its always producing new gametes rather than the females who have all of her gametes somehow already there? Perhaps that would be the reason why female gametes would get kind of age-worn?

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Just on this shortly:
First of all - their findings are not about classic genetics but something unusual.
They talk about free olfactory receptors in the bloodstream of other species, and note that there are olfactory receptors to be found in sperm as well. As far as I know, sperm use such receptors to find out where to swim to.
Sperm with receptors playing a role in our specific case here is a mere speculation, though - but if it were so - it would be a quite special and unusual case, I believe. It could well be, and is probably more likely, that "classical epigenetic happenings" are the mechanism here.

And I believe, it is rather the other way round with men and women adding something new! :cheeky:
But maybe not so, if you only look at epigenetics - you might have a point here - does somebody have an idea on that?

Otherwise and repeating myself - mutations bring in "diversity" and eggs and their DNA lie about for a long time, which means, that mutations are more likely to occur in eggs than sperm. An example for what causes mutations would be exposition to radiation but also mere chance.
Most mutations are "bad" for the organism in question - but not all of them - otherwise no evolution.

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Originally Posted by StephL

Yes - you could see it like this - but in the case of "the reptile brain" or "basic mammal brain" - it's not so, that these are the shabby old stuff.
They work beautifully well - and we wouldn't get overly far without them, too.
No fear, aggression, sexual desires - no love and compassion-base - not even Spok would get anywhere!

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Of course, you're right! I wasn't trying to say that the older parts of the brain are unnecessary, or that they've been deactivated, my point with the brain stuff was simply that evolution can only work by building onto already existing systems, and can't remove them. I think I tried to get across all that stuff I learned from Uncle Carl too briefly, just wanted to spit it out quickly and not take up too much space with it, so I reduced it too much and left my meaning a bit ambiguous. I sometimes do that, thanks for straightening it out Officer Spock! :rolllaugh:

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Originally Posted by StephL

Pööh! Attachment 7270

Well I found my little picture on 'descent with modification' also nice - only with rabbits and carrots, and without explaining why the light grey ones are better carrot munchers - but anyway!

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Yes, I said all of it was valuable, which includes that part! So touchy today! Sheesh! :chuckle:

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Originally Posted by StephL

Aand - another pöööh! That was "my tumour" which made you gag!! Attachment 7270

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Sorry, I didn't mean to attribute your tumor to Xei! I just got lazy and was writing the Xei paragraph when I brought that up - I know I mixed up my references. Ok, if it makes you feel better, it was YOU who made me gag, more than Xei! Better now? :pfft:

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Originally Posted by StephL

It is probably not so, that all and everything, which is in the human genome, can come to expression suddenly just like that. But remember the gills - you and me, we had them expressed already. What about more freaky stuff showing up in the final phenotype (the shape of an organism)?
As you found yourself - webbing is easy.
But once you have something rather extreme, you are quite likely going to end up as a tiny little blob of "blood" in sanitary trash after a very early spontaneous abort - completely unnoticed by the world. Gagging already? Attachment 7270

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Haha… well, I'm not eating right now, and hopefully I won't think of that when I am..

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Originally Posted by StephL

Another thing - we have a lot of so called "junk-DNA" - non-coding bits, which seem to be good for nothing. They could well come in for evolutionary purposes. When I studied, junk-DNA was just a riddle - but I believe nowadays we understand more about it..?

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Exploring the vast junkyard that is DNA :alien: (< mutant smilie)

Quote:

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Originally Posted by StephL

It is meanwhile possible to erase traumatic memories with drugs given at crucial points in time. But I guess, what you are getting at is completely different. I do not know, what you could mean and agree with Darkmatters - a link would be fine!

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I learned some time ago that apparently every time you recall a memory you're actually changing it, recalling is an active process that slightly 're-writes' the memory. Just on a related note, I haven't read the article yet.

Just teasing ya!
And I have a reputation to defend of being skilled in gleefully disgusting people with my science loving - especially while they are eating!

Attachment 7277

And yupp - memories are not stored somewhere like on a computer - every time you remember something - you change it in the process.
I would love to know much more about memory, actually - and it's not only me, not being very well acquainted with what we do know - there's a lot to be found out yet. I guess, you read my little "recapitulation from flawed memory" concerning this science fiction short story around how "perfect memory" would change our lives and all of society in Ginsan's transhumanism thread. Not so sure about some other things I wrote there, and how - but whatever. It's fascinating, how plastic our personal stories really are, and to wonder about the mechanisms, which for example lead us to rather forget the bad things in favour of the good things in our lives. Especially good things about ourselves - we all tend to polish our self-image up and sort out some painful truths in the process. I guess, this is a good thing because too much reality might make us depressed and socially awkward and miserable. It might be, that our cannabinoid receptors play a role there - we're not entirely sure, what purpose they might actually have.
There's a hypothesis about something called 'depressive realism'. I will spoiler the Wikipedia article on it, since I don't trust my memory enough for just going ahead and claiming it is a real thing - but I do believe that it is for certain situations!

Spoiler for Wikipedia on depressive realism:

Depressive realism is the hypothesis developed by Alloy and Abramson[1] that depressed individuals make more realistic inferences than non-depressed individuals. Although depressed individuals are thought to have a negative cognitive bias that results in recurrent, negative automatic thoughts, maladaptive behaviors, and dysfunctional world beliefs,[2][3][4] depressive realism argues not only that this negativity may reflect a more accurate appraisal of the world but also that non-depressed individuals’ appraisals are positively biased.[5] This theory remains very controversial as it brings into question the mechanism of change that cognitive behavioral therapy for depression purports to target.[6] While the evidence currently supports the validity of depressive realism, its effect may be restricted to a select few situations.[7]


Evidence for
When participants were asked to press a button and rate the control they perceived they had over whether or not a light turned on, depressed individuals made more accurate ratings of control than non-depressed individuals.[8] Among participants asked to complete a task and rate their performance without any feedback, depressed individuals made more accurate self-ratings than non-depressed individuals.[9][10][11][12] For participants asked to complete a series of tasks, given feedback on their performance after each task, and who self-rated their overall performance after completing all the tasks, depressed individuals again were more likely to give an accurate self-rating than non-depressed individuals.[13][14][15][16][17][18] When asked to evaluate their performance both immediately and some time after completing a task, depressed individuals made accurate appraisals both immediately after and after time had passed.[19] Finally, in an fMRI study of the brain, depressed patients were shown to be more accurate in their causal attributions of positive and negative social events than non-depressed participants who demonstrated a positive bias.[20] This difference was also reflected in the differential activation of the fronto-temporal network, higher activation for non self-serving attributions in non-depressed participants and for self-serving attributions in depressed patients, and reduced coupling of the dorsomedial prefrontal cortex seed region and the limbic areas when depressed patients made self-serving attributions.

Evidence against
When asked to rate both their performance and the performance of another, non-depressed individuals demonstrated positive bias when rating themselves but no bias when rating others. Depressed individuals conversely showed no bias when rating themselves but a positive bias when rating others.[21][22][23] When assessing participant thoughts in public versus private settings, the thoughts of non-depressed individuals were more optimistic in public than private, while depressed individuals were less optimistic in public.[24][25][26][27] When asked to rate their performance immediately after a task and after some time had passed, depressed individuals were more accurate when they rated themselves immediately after the task but were more negative after time had passed whereas non-depressed individuals were positive immediately after and some time after.[28][29] Although depressed individuals make accurate judgments about having no control in situations where they in fact have no control, this appraisal also carries over to situations where they do have control, suggesting that the depressed perspective is not more accurate overall.[30] When studied in real-world settings, depressed individuals are actually less accurate and more overconfident in their predictions about the future than their non-depressed peers.[31] Participants’ attributional accuracy may also be more related to their overall attributional style rather than the presence and severity of their depressive symptoms.[32]

Criticism of the evidence
Some have argued that the evidence is not more conclusive because there is no standard for "reality," the diagnoses are dubious, and the results may not apply to the real world.[33] Because many studies rely on self-report of depressive symptoms, the diagnosis of depression in these studies may not be valid as self-reports are known to often be biased, necessitating the use of other objective measures. Due to most of these studies using designs that do not necessarily approximate real-world phenomena, the external validity of the depressive realism hypothesis is unclear.[clarification needed] There is also concern that the depressive realism effect is merely a byproduct of the depressed person being in a situation that agrees with his or her negative bias.[34][35][36]

Wow! I love how this thread 'evolved'...

First of all I want to sum up what I have understood about the process of evolution which is not how it was taught to me, in the conventional way of a single change in a species, that have a start and an end. Actually, according to what was told here so far, it's a constant process that doesn't stop. The only thing that could stop is the change in the environment, right?

I can distinguish 3 stages of this constant natural process called 'evolution'. One would be a 'stationary' stage where there's a stable environment and there's not a big differentiation between the individuals of the same species, although there are slight variations (aka mutations) between all of them which go unnoticed because of they're not 'needed', therefore most of the individuals will look like almost the same. The second stage would be when there's a change in the environment, which would force the individuals to adapt to it. In this stage, those slight variations would benefit some of them while others not, it would even be harmful to others. In the third stage, the variations of the individuals of the next generations will start to be significantly noticeable compared with the initial ones, that is in favor of the adaptation to the new environment which now, will turn into a new stationary stage. (Things already said I think, just I'm reinforcing my new neural connections). I could see the process of evolution like a flowing stream, where life is sort of a source of flowing water (sort of self replicating drops in this case) and it will flow to where its source of energy is. The process of evolution, could be understood somehow like the course of a river. If you put a dam, the water will stay for a while and turn, until it finds a new way to reach the lower places pulled by gravity. Generating different pools along its way. Those pools would be the different species.

Now, about the memory process. It is known that a memory implicates most (if not all) of the neurons that were involved during a experience. Memories are malleable by the process of thinking, that is to say, they are not unalterable in time. There are different types of memories and it's main purpose is survival. What called my attention about the process of evolution taking place influenced by this process of memory was its possible application in relation to the article about the technique where a memory could be erased or restored by pulses of light (aka electromagnetic waves). I know there is a strong moral restriction there, and perhaps my ideas as usual would sound a bit over the edge about what can be done or not. But I was fascinated by the idea of how it was possible to alter the synapse using a virus to deliver a gen into the neuron which produced a light-responsive protein, that once stimulated by a nano-led inserted into the brain close to the region, it could turn on and off those connections. I was wondering how about if in stead of inserting nano-devices in the brain, the resulting protein could be responsive to other frequencies of electromagnetic waves? The way to deliver the gen to certain regions of the brain would be by the blood flow, I don't know, if it's known that during brain activity there's a major blood flow in those regions, why not take advantage of that? Well, that was my 'scientific trip', and I was wondering if it would be possible to genetically alter the DNA sequence by using the same system.

The technique is named 'Optogenetics', and here's an additional article, which I forgot (:tongue: again) to mention: A device that controls your mind with pleasurable stimulation

One more edit: I've just found this article recently spread on the web: Family violence leaves genetic imprint on children -- ScienceDaily

That's a pretty accurate description of evolution, Box. The water metaphor is rather nice. Note how everything you said is completely uncontroversial, and the conclusion is therefore sound. A lot of creationists accept the uncontroversial facts as facts but then somehow deny the conclusion, which is like accepting that Los Angeles is in California and that California is in the USA but refusing to accept that Los Angeles is in the USA. The undeniable facts are that species have variation, including some rather extreme variants due to potent mutations; that this variation is passed down to children; and that some variants are better suited to the environment and will hence survive more and have more children. You could say that these roughly correspond respectively to the fact that water likes to spread outwards; the fact that water moves in continuous blobs; and the fact that water prefers lower pools. When these facts are granted, evolution is no longer in question; indeed the question is why on Earth evolution wouldn't happen after a change in environment. On top of this logical argument of course, there's also a mountain of direct empirical evidence mentioned earlier.

To answer your earlier questions about how life could have got started in the first place, it's a very good question. This topic is called "abiogenesis". Although we don't have a historical record, in the same vein as the preceding paragraph, we can observe various interesting things which do indeed happen, and piece them together. The first is that the organic molecules you alluded to, including DNA, RNA (which is essentially a single-stranded variant of DNA used by cells to translate DNA into the actual physical molecules it codes for, namely proteins), proteins (which are the molecules that control all activity in the cell), and then basic building materials like sugars and fats, do arise by themselves, as blind chemical process with no help required. The most famous experiment regarding this was the "Miller-Urey" experiment, where they basically put the gases of Earth's early atmosphere into a jar with some energy. After some time this produced a rich organic gloop which contained, among other things, all 20 of the amino acids used by life - a protein is just a string of amino acids. Later, similar experiments also produced the five nucleobases which are strung together to make RNA and DNA. In addition, it's a common experience that fats like oil will spontaneously form balls when in water, rather than mixing. There's a simple variant of fats called "phospholipids" which, in the same way, will spontaneously form a spherical wall. Thus cell membranes, too, can form all by themselves.

So it's not in question that the building blocks of cells and life can and do form spontaneously due to the blind action of chemical laws. There's still a big explanatory gap from building blocks to an actual building, though. The clue to bridging the gap is in molecules called "ribosomes". These are the molecules which translate RNA into proteins. The interesting thing is that unlike almost all other molecules responsible for a cell's activities, ribosomes aren't solely made of protein; they are largely made of RNA. Other active RNA molecules have been discovered, but the ones in ribosomes are particularly interesting because they are themselves acting on RNA. This is very intriguing because it suggests RNA could act on other RNA, without the prerequisite of the presence all of the other complex machinery like DNA and proteins - which otherwise poses something of a "catch 22" mystery. This idea of an initial "RNA world" would then explain the surprise of the ribosome not being purely protein as a kind of ultimate ancestral hangover - a necessary pathway to the emergence of life which can't be redesigned afterwards.

So RNAs can create other RNAs. The last piece in the puzzle would be an RNA molecule (or perhaps two or more RNA molecules) which creates RNAs which are copies of itself - and at a rate greater than the rate at which it was destroyed (i.e. a birth rate exceeding the death rate). Once it came into existence (by RNA bases randomly sticking together in the right order), the RNA strand would multiply through its environment very quickly. Then you would have "mutations"; imperfect copies which were more stable and/or faster at reproducing, and which would, therefore, quickly replace the old molecule - and so on. So you can see at this point, we would essentially have life and natural selection. And scientists have synthesised RNA molecules which come very close to being able to replicate themselves: what they do is replicate other RNA molecules they come into contact with. The caveat is that the molecules they replicate are shorter than themselves; but this is not a fundamental problem. All that's needed is an RNA that can replicate longer molecules, or perhaps another RNA working in tandem to piece together the short sections - and from that, life would follow.

Oh Box - you are talking about optogenetics!!
I will check out your links and think about it all, and get back to you on your paragraph on memory!
Just wanted to say how well I remember, when I first read about it in 2009 in a German scientific magazine.
I was so excited, that this episode is really "well imprinted" - I know, that I was sitting in a bus in Berlin, I even remember how the bus interior looked and where I sat, that it was hot and I had taken my shoes off.

When you look back at a certain time of your life and search out indiscriminatingly - or you search for something specific, which happens to be special - my experience is, that the episodes which come up are comparable to gold nuggets - patches of context around something, which used to hold emotional importance for you. As if memory would work like a sieve for extracting gold from muddy river waters. Na well. Maybe not the best metaphor, for what I want to express.

And optogenetics - I have to say - it thoroughly enthused me back then in my bus!!
I've been reading about it later on as well - but you present a good opportunity to get my nose back into it!
'Nature' has selected the technique as the method of the year 2010 and produced the below video.
And it is (still) expected, that the developers will eventually get decorated with Nobel Prizes.
A bit of a squeaky voice, but great graphics and information:

http://www.youtube.com/watch?v=I64X7vHSHOE


Me and my picture-mania - as you can see, the virus needed to be injected directly into the brain - and because of a specific promotor
gene-sequence - it only comes to expression in certain targeted cells:

http://i1339.photobucket.com/albums/...pscfedde3b.jpg
http://i1339.photobucket.com/albums/...ps2a31ff0b.jpg

http://www.robotspacebrain.com/wp-co...togenetics.png

She doesn't look unhappy or tortured, now does she? :wink:
Well - but it's not nice of course to be born a Parkinson sufferer by genetic manipulation, even if she then gets partly "healed by the light".
But it's important and justified in my opinion! If you eat meat - you shouldn't be hypocritical about these things!

One more:

http://ibro.info/wp-content/uploads/...ic-709x267.jpg


Edit: I find this soo great, that you came to understand evolution thanks to this thread here - something your school failed to accomplish, Box!!

Xei: I knew I was onto something when I pointed the behavior of ferrofluids (yes Steph, one of those videos) perhaps it wasn't that accurate but that gave me a clue to illustrate that there was the possibility of generating such molecules without a 'divine intervention', just atomic forces. It would be also corroborated by the presence of vitamin B3 in those meteorites mentioned in the other article which I could infer from there, that the presence of such complex molecules in the universe could be more ordinary than we think. Definitively I will check more about abiogenesis. Thanks for your time to expand the knowledge on this topic!

Steph: I know what you mean when you talk about your impressions in the Bus, right now I'm having that kind of impression (Not in a Bus :cheeky:) that perhaps later I will remember with the same enthusiasm. The video you posted there, was something I wasn't able to find when I first read about optogenetics. Thanks for sharing! And your pics are very illustrative. It was something that used to happen with me during university (as long as I was able to tolerate their system) when studying Math and Physics, it was easier for me to understand some concepts with the graphics. By the way, now I understand why somebody told me that 'Pinky and the Brain' was not a joke.

Quote:

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Originally Posted by StephL

I find this soo great, that you came to understand evolution thanks to this thread here - something your school failed to accomplish, Box!!

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:content: Perhaps the best thing my school accomplish to do, was to get rid off me :chuckle:

Could it maybe be said, that evolution is responsible for the phenomenon, that the range of colour is the same for most of us creatures,
for all to see, so to speak?
Agreeing with each other on what to see?
Just a probably silly idea, before falling into bed, exhausted...

^^Apparently photo-receptors evolved from a cell which was sensitive to some range of electromagnetic waves which included the frequencies we are capable to see, like the range of blue for example.

Well, I would like to add a link I find interesting related to the process of evolution in order to guide other people interested in the subject from a scientific point of view and not necessarily skilled in the matters, like me and many others who I think, are willing to understand this little world around us just for curiosity and not by force:

Sharks' Sixth Sense Related to Human Genes

Short explanatory video about that 'sixth sense' here.

I would like to point out a paragraph from that article: "It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors"

Does anybody know if that "definitive experiment" already took place? That article dates from 2006. The one I found in National Geographic date back in 2010 but basically it says the same.

It looks to me as if you guys in here would have been so nice as to wait up for me - if so - thank you soo much - you are really sweet!
I want to apologize to yall for that - I am really sorry for bringing threads to a grinding halt like this.

So now I am back again - at least for now and hopefully for longer – I had a lot of free time on my hands – which is not exactly a bad thing – I got some amazing amount of fun things done – besides important things as well.

First of all - one of those fun things was following up on your two links Box77!
Unfortunately one doesn’t work – the meteor one. But the other does and it contains red-hot stuff I would say!

Once more:
A New Technique Could Erase Painful Memories -- Or Bring Them Back

Fascinating how much more fine-grained our understanding of memory is these days that such specific manipulations are possible! But it's pretty easy to get fantasies of mind-control and brainwashing like in the movies with on and off buttons here, too!
Okay – here goes – the usual – I indiscriminately suspect everybody including myself of laziness in clicking through:

Quote:

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A New Technique Could Erase Painful Memories -- Or Bring Them Back

By using pulses of light, researchers at the UC San Diego School of Medicine have produced, erased, and restored fearful memories in rats. It's a finding that could have profound implications for people struggling with neurodegenerative and anxiety disorders.
The study, though not the first to implant a memory in a rodent, is the first to selectively remove a memory — in this case, a conditioned fear response — and then predictably reactivate it by stimulating nerves in the brain at frequencies known to weaken and strengthen the connections between synapses. It's probably the most sophisticated memory engineering experiment done to date.
What's more, the study confirms a long-standing theory about how memories are made and stored in the brain. The experiment suggests that the weakening of specific nerve cells likely disassembles neuronal circuits, resulting in the inactivation of a memory. This confirmation hints at future therapies in which neuroscientists can take control of runaway emotional memories in mental illnesses, such as post-traumatic stress disorder.

Let There Be Light

Neuroscientists theorize that memories are formed when connections between neurons are strengthened — a process facilitated by mechanisms such as long-term potentiation (LTP) and long-term depression (LTD). But this has been difficult to demonstrate in the lab. This latest study, which was conducted by Roberto Malinow of the University of California, San Diego, Roger Tsien of NIH's National Institute on Neurological Disorders and Stroke (NINDS), and other UCSD colleagues, proves that a causal link exists between these synaptic processes.
It was a confirmation made possible by the burgeoning field of optogenetics — a technique in which a gene is delivered to the brain cell of an animal using a special virus. Once delivered, the gene produces a series of light-responsive proteins which can either be activated or disabled by fiber optic cables inserted into the brain. To date, neuroscientists have used the technique to induce sensations, memories, and behavioral changes in mice and monkeys. In the new experiment, pulses of fibre optic light were used to both remove and reactivate conditioned responses in rats.

http://i.kinja-img.com/gawker-media/...eizcgzc9yi.png

Engineering Memory

The first stage of the experiment was to produce a conditioned fear response in the rats. The scientists did so by optically stimulating a group of nerves in rats' brains that had been genetically modified to make them sensitive to light. At the same time, the researchers delivered an electric shock to the rats' feet. The rats thus learned to associate the optical nerve stimulation with pain, thereby triggering fearful behavioral responses. Subsequent analysis showed that the resulting chemical changes were consistent with synaptic strengthening.

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I wonder, what exactly they might mean by that - were they able to show that actual LTP or LTD (long term potentiating/depression on the level of synaptic micro-anatomy) has taken place? Which chemicals have they measured and where?

Quote:

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Following this stage, the scientists weakened this neural circuitry by stimulating the same batch of nerves with a memory-erasing, low frequency train of optical pulses. Following this, the rats no longer responded in a fearful way to the original nerve stimulation. The memory had, for all intents-and-purposes, been erased.
For the final and most astounding step, the neuroscientists restored the memory by re-stimulating the same nerves with the memory-forming, high-frequency train of optical pulses. Subsequent experiments shows that the rats were once again responding to the original stimulation with fear.
"We can cause an animal to have fear and then not have fear and then to have fear again by stimulating the nerves at frequencies that strengthen or weaken the synapses," noted lead author Sadegh Nabavi in a statement.

Looking to the future, and in addition to treating anxiety disorders, a similar technique could be used to treat age-related neurodegenerative diseases, such as Alzheimer's. But that's a far way's off; we still don't know how humans will respond to optogenetics. Moreover, for it to work in us humans, we'll have to be genetically modified to respond to the light in specific ways, and have the genes delivered to our brains via viruses. There's clearly a lot of work — and ethical objections — that still need to be overcome.

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On my raid through Mr. Kurzweil’s wonderful transhumanism et cetera page – I came across something on memory formation, which doesn't equate with classical LTP:
Synchronized brain waves enable rapid learning | KurzweilAI

What they propose here, is that there is another, faster and more flexible way of learning besides or maybe prior to LTP/LTD. Which is long-term-potentiation/-depression on the level of micro-anatomy, actual synapses – what they talk about in Box77’s article for memory engineering. Especially categorical learning which is of a higher order than simple conditioned fear seems to be taking place in form of different brain areas synchronizing their firing rhythms. Before this learning takes place each of the areas only sings its own song:

Quote:

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Synchronized brain waves enable rapid learning

Why brain-wave resonance may be the key to learning, not synapses

MIT neuroscientists have found that as monkeys learn to categorize different patterns of dots, two brain areas involved in learning — the prefrontal cortex and the striatum — synchronize their brain waves to form new communication circuits.

“Category-learning results in new functional circuits between these two areas, and these functional circuits are rhythm-based, which is key because that’s a relatively new concept in systems neuroscience.”
There are millions of neurons in the brain, each producing its own electrical signals. These combined signals generate oscillations known as brain waves, which can be measured by electroencephalography (EEG). The research team focused on EEG patterns from the prefrontal cortex — the seat of the brain’s executive control system — and the striatum, which controls habit formation.

The phenomenon of brain-wave synchronization likely precedes the changes in synapses, or connections between neurons, believed to underlie learning and long-term memory formation, Miller says. That process, known as synaptic plasticity, is too time-consuming to account for the human mind’s flexibility, he believes.

“There’s got to be some way of dynamically establishing circuits to correspond to the thoughts we’re having in this moment, and then if we change our minds a moment later, those circuits break apart somehow. We think synchronized brain waves may be the way the brain does it.”

Humming together

Miller’s lab has previously shown that during category-learning, neurons in the striatum become active early, followed by slower activation of neurons in the prefrontal cortex. “The striatum learns very simple things really quickly, and then its output trains the prefrontal cortex to gradually pick up on the bigger picture,” Miller says
“The striatum learns the pieces of the puzzle, and then the prefrontal cortex puts the pieces of the puzzle together.”

http://www.kurzweilai.net/images/MIT...JLOlivares.jpg

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This should cause some joy among those, who “always said it’s all about rhythm, waves and what have you”. Yupp – but you got to know, what you are talking about to make sense!


So – such a long post already – and I didn’t even answer your latest posts yet, Box77!

Quote:

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Originally Posted by Box77

Steph: I know what you mean when you talk about your impressions in the Bus, right now I'm having that kind of impression (Not in a Bus ) that perhaps later I will remember with the same enthusiasm. The video you posted there, was something I wasn't able to find when I first read about optogenetics. Thanks for sharing! And your pics are very illustrative. It was something that used to happen with me during university (as long as I was able to tolerate their system) when studying Math and Physics, it was easier for me to understand some concepts with the graphics. By the way, now I understand why somebody told me that 'Pinky and the Brain' was not a joke.

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Thank you!

Quote:

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Originally Posted by StephL

Could it maybe be said, that evolution is responsible for the phenomenon, that the range of colour is the same for most of us creatures,
for all to see, so to speak?
Agreeing with each other on what to see?
Just a probably silly idea, before falling into bed, exhausted...

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Doesn’t really make sense – at least not like this – I might start on over with it one day.

Quote:

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Originally Posted by Box77

^^Apparently photo-receptors evolved from a cell which was sensitive to some range of electromagnetic waves which included the frequencies we are capable to see, like the range of blue for example.

Well, I would like to add a link I find interesting related to the process of evolution in order to guide other people interested in the subject from a scientific point of view and not necessarily skilled in the matters, like me and many others who I think, are willing to understand this little world around us just for curiosity and not by force:

Sharks' Sixth Sense Related to Human Genes

Short explanatory video about that 'sixth sense' here.

I would like to point out a paragraph from that article: "It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors"

Does anybody know if that "definitive experiment" already took place? That article dates from 2006. The one I found in National Geographic date back in 2010 but basically it says the same.

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Very interesting! Thank you!!

Sharks can detect electricity and the below article says that probably a direct ancestor of ours with a spine could do that too. Genetic material pertaining to it is in the human genome, and plays a role in forming head and face features of ours.

There is a very attractive jump in reasoning, which could be made, but I guess they are not implying it with their experiment.

I think, they want to dye these neural crest cells in order to watch where they migrate and if the dye shows up in the electroreceptors.
Not in order to show how colour molecules could have found entry into such cells like suggested in the Sagan video - if you mean that?
He had his neural crest of electro-receptive cells and they came to contain "colour-molecules" - dye. If I remember this correctly now.
This is crucial to vision – you need a molecule, which is able to respond to light by changing molecular conformation and thus provide a signal, which can then be further processed.

They say there might be a connection to our sense of balance from the inner ear.
But who knows? Maybe they are the same cells, Sagan has been talking about anyway?

Now upon editing I am not entirely sure of some things actually... Attachment 7319
Soo – could we maybe get electro-receptivity back with retro-gene-engineering?!
It would only enable us to swim straight and other minor things I am afraid, though.

One more exhaustive quote - its exteeended discussion here after all and it’s interesting:
Sharks' Sixth Sense Related to Human Genes

Quote:

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Sharks' Sixth Sense Related to Human Genes

The same genes that give sharks their sixth sense and allow them to detect electrical signals are also responsible for the development of head and facial features in humans, a new study suggests.
The finding supports the idea that the early sea creatures which eventually evolved into humans could also sense electricity before they emerged onto land.
The study, led by Martin Cohn and his lab at the University of Florida, is detailed in the current issue of the journal Evolution & Development.

Sixth sense

Sharks have a network of special cells that can detect electricity, called electroreceptors, in their heads. They use them for hunting and navigation.
This sense is so developed that sharks can find fish hiding under sand by honing in on the weak electrical signals emitted by their twitching muscles.

The researchers examined embryos of the lesser spotted catshark. Using molecular tests, they found two independent genetic markers of neural crest cells in the sharks' electroreceptors. Neural crest cells are embryonic cells that pinch off early in development to form a variety of structures. In humans, these cells contribute to the formation of facial bones and teeth, among other things.

The finding suggests that neural crest cells migrate from the sharks' brains to various regions of the head, where they develop into electroreceptors.
Glenn Northcutt, a neuroscientist at the University of California, San Diego, who was not involved in the study, said the finding was interesting, but that more studies are needed before a direct link between neural crest cells and electroreceptors can be established.
"It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors," Northcutt said.
In the new study, the researchers found snippets of genetic material associated with neural crest cells in the electroreceptors. They did not dye the neural crest cells and trace their development.

Our electrical ancestors

Scientists think that all primitive animals with backbones, including the early ancestors of humans, could sense electricity. As they evolved, mammals, reptiles, birds and most fish lost the ability. Today, only sharks and a few other marine species, such as sturgeons and lampreys, can sense electricity.
"Our fishy ancestors had the anatomy for it," said study team member James Albert, a biologist from the University of Louisiana.
The ability to sense electrical signals is useful in aquatic environments because water is so conductive. On land, however, the sense is useless.
"Air doesn't conduct electricity as well," Albert said. "When it happens, it's called a lightning bolt and you don't need special receptors to sense it."
The development of the electroreceptors is believed to mirror the development of the lateral line, a sense organ in fish that allows them to detect motion in surrounding water. Similar processes are thought also to be involved in the development of the inner ear, the organs which help humans keep their balance.
The electroceptors are also believed to behind many sharks' ability to detect changes in the Earth's magnetic field. Other studies indicate that like sailors, sharks can also navigate by celestial cues.
Scientists think that these two abilities are what allow some sharks to swim straight lines across vast distances of featureless ocean. One recent study found that a great white shark, nicknamed Nicole, swam nearly 7,000 miles between South Africa and Australia in just under 100 days.

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Thanks also for the video - I didn't watch it yet, though. But why oh why does it have to use the term Extrasensory Perception (ESP)?? It is clearly all about exactly and only sensory perception after all! And thank god for that! :wink:
Is it to lure in otherwise unwilling audience? Well maybe then that’s okay - or so.

I have something sweet on “how evolution made us human” – comes later maybe.

Quote:

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Originally Posted by StephL

It looks to me as if you guys in here would have been so nice as to wait up for me - if so - thank you soo much - you are really sweet!
I want to apologize to yall for that - I am really sorry for bringing threads to a grinding halt like this.

So now I am back again - at least for now and hopefully for longer – I had a lot of free time on my hands – which is not exactly a bad thing – I got some amazing amount of fun things done – besides important things as well.

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It's nice to see you again!! :happyface: Welcome back!!

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Originally Posted by StephL

Unfortunately one [of the two links] doesn’t work – the meteor one.

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I checked it and it still working.. hmm.. Although I think what Xei said about abiogenesis was pretty explanatory about the subject, besides a couple of days ago I found this article here: Origin of life: Stanley Miller's forgotten experiments, analyzed -- ScienceDaily and I think it basically supports what Xei said.

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Originally Posted by StephL

This is serious business – they only mention the benign, the good purposes for which it could be used – my fantasy runs wild on it, though. Now there we have all we need for good old brainwashing even with switching on and off – just like in the movies! This could be massive discussion-fodder, actually!

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I think you get it! If memories can be removed, restored and possibly artificially implanted, and if memory could affect the way how genes are transmitted from one generation to another then it would be possible to direct the way how an organism could evolve? I don't know, just an idea but it could be one of those subjects of friendly discussion.

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Originally Posted by StephL

What they propose here, is that there is another, faster and more flexible way of learning besides or maybe prior to LTP/LTD. Which is long-term-potentiation/-depression on the level of micro-anatomy, actual synapses – what they talk about in Box77’s article for memory engineering. Especially categorical learning which is of a higher order than simple conditioned fear seems to be taking place in form of different brain areas synchronizing their firing rhythms. Before this learning takes place each of the areas only sings its own song:

This should cause some joy among those, who “always said it’s all about rhythm, waves and what have you”. Yupp – but you got to know, what you are talking about to make sense!

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I think it could be a part of a whole, but it's a very interesting article and perhaps it could support some other thread about inducing some signals to stimulate some regions of the brain (:hrm:Was it the frontal lobe?) to produce awareness in dreams or so.

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Originally Posted by StephL

Sharks can detect electricity and the below article says that probably a direct ancestor of ours with a spine could do that too. Genetic material pertaining to it is in the human genome, and plays a role in forming head and face features of ours.

There is a very attractive jump in reasoning, which could be made, but I guess, it is not meant so. Namely that these electroreceptors of sharks, consisting of electro-receptive cells, could be a progenitor cells of our eyes. I think, they want to dye these cells in order to watch where they migrate – not in order to show how colour molecules could have found entry into these cells like suggested in the Sagan video. He had his crest of electroreceptive cells and they came to contain "colour-molecules" - dye. If I remember this correctly now.
This is crucial to vision – you need a molecule, which is able to respond to light by changing molecular conformation and thus provide a signal, which can then be further processed. I suppose, the shark’s sixth sense is not thought to be connected to our vision. I believe the article rather says, that we might have the genetic information for that sixth sense. And that there might be a connection to our sense of balance from the inner ear.
But who knows? Maybe they are the same cells, Sagan has been talking about anyway?

Soo – could we maybe get electro-receptivity back with retro-gene-engineering?!
It would only enable us to swim straight and other minor things I am afraid, though.

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Actually, I was just pointing one more example of evolution and how could we be related to our ancestral marin-super-hyper-grand-grand-grand-parents :tongue:, but as it needed still to be definitively confirmed, it cannot be claimed as a fact and we can only speculate about it until that definitive experiment takes place... it's interesting though, your point about how could it be related to the vision, although I think the article infers that other structures developed from those ancient sensors.

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Originally Posted by StephL

Thanks also for the video - I didn't watch it yet, though. But why oh why does it have to use the term Extrasensory Perception (ESP)?? It is clearly all about exactly and only sensory perception after all! And thank god for that! :wink:
Is it to lure in otherwise unwilling audience? Well maybe then that’s okay - or so.

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The text apparently is trying to call some attention to show some real stuff in youtube.

Edit: By the way, I forgot to mention another article I found interesting about the processing of information in the brain. I don't know if it could be related to what is discussed about memory, but I let you the link anyway: Clever Suppression in the Brain: Diversity of inhibiting nerve cells allows for more complex information processing | neuroscientistnews.com

Hi Box77!
Thank you!
Attachment 7320

I found this: Why Language Is All Thumbs | KurzweilAI

How did we become human beings? All living things are unique. The forces that drive evolution make them so, honing each down to the razor edge of itself, providing it with a handful of qualities that distinguish it as the only animal of its kind. The elephant has its trunk. Bombardier beetles manufacture and precisely shoot boiling hot toxic chemicals from their tails. Peregrine falcons have wings that propel them unerringly through the air at seventy miles an hour to their catch. These traits define these creatures and determine the way they act. But what unique traits shape and define us? I have whittled it down to six, each unique to our kind: our big toes, our thumbs, our uniquely shaped pharynx and throat, laughter, tears, and kissing. How, you may ask, can something as common as a big toe, as silly as laughter, or as obvious as a thumb, possibly have anything to do with our ability to invent writing, express joy, fall in love, or bring forth the genius of ancestral China? What could they have to say about rockets and radio, symphonies, computer chips, tragedy, or the spellbinding art of the Sistine Chapel? Just this.

The origin of all these human accomplishments can be traced to these traits, each of which marks a fork in the evolutionary road where we went one way and the rest of the animal kingdom went the other, opening small passageways on the peculiar geography of the human heart and mind, marking trailheads that lead to the tangled outback of what makes us tick. Take the knobby big toes we find at the ends of our feet. If they hadn’t begun to straighten and strengthen more than five million years ago our ancestors would never have been able to stand upright, and their front feet would never have been freed to become hands. And if our hands had not been freed we would not have evolved the opposed and specialized thumbs we have, which made the first tools possible.

Both our toes and thumbs are linked to the third trait—our unusual throats and the uniquely shaped pharynx inside, which enables us to make more precise sounds than any animal. Standing up straightened and elongated our throats so that our voice box dropped. In time that made speech possible, but we also needed a brain that could generate the complex mental constructions that language and speech demand. Because toolmaking required a brain that could manipulate objects, it supplied the neural foundations for logic, syntax, and grammar so that eventually it could not only take objects and arrange them in an orderly manner, it also could conceive ideas for our pharynx to transform into the sound symbols we call words and organize them so they made sense as well.

A mind capable of language is also a self-aware mind. Consciousness melded our old primal drives with our newly evolved intelligence in entirely unexpected ways that even language couldn’t successfully articulate. This explains the origins of laughter, kissing, and crying. Though we can glimpse their origins in the hoots, calls, and ancient behaviors of our primate cousins, no other species carries these particular arrows in the quivers they use to communicate.

© 2006 Chip Walter


Only a little excerpt - but it makes a load of sense...

^^ Perhaps there's something interesting about language evolution too:

- The evolution of language: Babel or babble? | The Economist

- Before babel: in search of the first language

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Originally Posted by Box77

^^ Perhaps there's something interesting about language evolution too:

- The evolution of language: Babel or babble? | The Economist

- Before babel: in search of the first language

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Originally Posted by Economist link

It looks, then, as if the correlations between grammatical features noticed by previous researchers are actually fossilised coincidences passed down the generations as part of linguistic culture. Nurture, in other words, rather than nature. If Dr Dunn is correct, that leaves Dr Chomsky's ideas in tatters, and raises questions about the very existence of a language organ.

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Very, very interesting article! And it's also nice to read, that there are scientific counter-arguments to Dr. Chomsky's ideas on language and mind.
I have actually forgotten why I came to strongly disagree with him on something more than ten years ago - something didn't compute in my view. But his modules and "language organ" were and still are the leading concept in linguistics. So language has probably only come to pass once and back in Africa - and there are no fixed grammatical correlations which are ubiquitous, common in different language groups.

I will watch the documentary tonight I guess - also looks very enticing!




I have something rather silly in comparison - but striking and on topic it is non the less:

Newly Discovered Mouse-like Mammal Is Closely Related to Elephants

Jun 26, 2014
By Laura Zuckerman

(Reuters) - A new mammal discovered in the remote desert of western Africa resembles a long-nosed mouse in appearance but is more closely related genetically to elephants, a California scientist who helped identify the tiny creature said on Thursday.

The new species of elephant shrew, given the scientific name Macroscelides micus, inhabits an ancient volcanic formation in Namibia and sports red fur that helps it blend in with the color of its rocky surroundings, said John Dumbacher, one of a team of biologists behind the discovery.

Genetic testing of the creature – which weighs up to an ounce (28 grams) and measures 7.5 inches (19 cm) in length, including its tail – revealed its DNA to be more akin to much larger mammals.

"It turns out this thing that looks and acts like shrews that evolved in Africa is more closely related to elephants," said Dumbacher, a curator of birds and mammals at the California Academy of Sciences in San Francisco.

The findings, published in the Journal of Mammalogy, floored scientists, who said the only visible link between an African elephant and the diminutive shrew is its trunk-like nose.

An elongated snout is a common feature of various shrew species, many of which look like long-nosed mice externally, though shrews are not classified as rodents.

Dumbacher likened the newly discovered mammal to a small antelope in its physique and sleeping habits and to a scaled-down anteater in hunting techniques and preferred prey.

Like an antelope, the creature has long, spindly legs relative to its body size, and hunkers down next to bushes to sleep rather than burrowing. Like an anteater, it uses its extended nose to sweep the ground in search of ants and other insects.

The desert-dwelling shrew is prone to giving birth to twins, which hit the ground running like the calves of some types of African antelope.

Biologists plan to return to Africa in the coming months to outfit the new mammals with miniscule radio collars to learn more about their habits, Dumbacher said.




This is not the brand-new one, but also an elephant shrew - I always found them lovely - and soo fast!!

http://www.youtube.com/watch?v=Nzj6cex6pgA

Talking about curious body changes, recently one of my kids asked me about how an animal gets 'transformed' into another. I showed her some illustrative videos about evolution, and in one of those, it was told how wolves are related to whales. Then I was thinking about some time lapse animations like this one here:

Evolution of Whales Animation - YouTube

Then I was wondering about how would it look like if I turn the time lapse video into real time speed, taking into account that the average video rate is 29.99 fps (practically 30 pictures per second):

Pakicetus ---> Ambulocetus

48 000 000 --> 47 000 000 yrs

for 1 000 000 yrs ~ The sequence lasts around 7 sec which means there are around 210 pictures in it, then:

If 29.99 [30] fps --> in 7 seconds there are 209.93 [210] frames; in 1 000 000 years --> it would be showing 1 frame each 4763.5 years.

Ambulocetus -> Maiacetus

47 000 000 --> 46 000 000

1 000 000 ~ 6 sec

29.99 [30] fps --> 179.94 [180] frames in 1 000 000 years --> 1 frame each 5557.4 years.

Maiacetus ---> Dorudon

46 000 000 --> 37 000 000

9 000 000 ~ 6 sec

29.99 [30] fps --> 179.94 [180] frames in 9 000 000 years --> 1 frame each 50016.7 years.

Dorudon -----> Llanocetus

37 000 000 --> 34 000 000

3 000 000 ~ 7 sec

29.99 [30] fps --> 209.93 [210] frames in 3 000 000 years --> 1 frame each 14290.5 years.

If my maths are still ok and I'm helping my daughter in the right way, I think it's not difficult to infere from my vague calculations that it would be like saying that in the sequence of changing from the Pakicetus into the Ambulocetus, for example, it would take more than 4500 years to go from one frame to another (Remember? There are still 208 more frames in this first sequence ;-)). That is to say, since the time when the great pyramid of Giza was built until now, we would be seeing practically the same kind of animal, and so on...

I'm reading a fantastic book at the moment called "Why We Get Sick" by Randolph M. Nesse. I came to it, because Dawkins recommended it somewhere. So do I!

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We can cure hundreds of ailments, but we understand remarkably little about why diseases exist at all. Why do we crave the very things that make us sick? Why, after thousands of generations, hasn't natural selection eliminated cancer, schizophrenia, and other scourges and evolved us into perfect human beings? Such questions are at the heart of the new discipline called Darwinian medicine, which applies the principles of evolutionary biology to the problems of medicine. The result of a unique collaboration between the chief architects of this new science - a groundbreaking Darwinian physician and one of the pioneers of modern evolutionary theory - Why We Get Sick offers a whole new set of scientific questions and suggests new ways of understanding illness. Finding evolutionary explanations for why we get sick - infectious agents that evolve faster than we do, environmental novelties, genes that are selected despite the fact that they cause disease, defenses, design compromises, evolutionary legacies - can help us uncover new, more effective methods of treatment. It can help resolve medical quandaries - for example, when is it best to let a fever run its course and when best to bring it down with medication? It offers a new view of disease that changes the relationship between our bodies and ourselves. Why We Get Sick takes the first major step toward reconceiving medicine as we approach the twenty-first century. Incorporating an evolutionary perspective into our understanding of illness will revolutionize the art and science of medicine and enable its practitioners to come close to achieving its ancient goals: To cure, sometimes. To help, often. To console, always.

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It's for people, who are willing to strain their grey cells a bit - but perfectly understandable, if the will is there and highly fascinating.

Many interesting things, many of them I didn't know - like about our appendix - it's left over from stages in evolution, where we digested less nutrient rich foods. Rabbits for example have one, or better a coecum, which does a useful job in this. So - we don't need it, other simians neither - so it gets smaller and smaller. Buut - once it has a certain thinness, the risk of an inflammation with infection causing swelling, which obstructs the only artery delivering blood to it rises. If it is obstructed - there's no defence any more against said infection, bacteria multiply like mad - the thing ruptures into the free abdominal cavity and thus turns deadly. While there is selection going against it - at a certain stage, the smaller it gets - the worse. So appendicitis, seemingly the only thing it "does", besides minor contributions to the immune system - might actually keep the thing alive, so to speak. Some of the book is - explicitly so - speculation, but much of it is well known, just usually not viewed from an evolutionary perspective.
Stuff like that - also interesting ideas and speculations on senescence and, and, and...

Hmmm, this mushroom like fiend may upset the current scheme for the tree of life:

Weird mushroom-shaped animals may rewrite animal family tree (Science Alert)

I'm going to make the not too teribbly educated guess that this will turn out to be a missing link between fungi and animalia because superficial similarities ftw!

Uuii - something new!!

http://www.sciencealert.com.au/image...s/mushroom.jpg

I hope they will find more of these to make a genetic analysis and see, where they fit in - shame they only have old samples in formaldehyde.

Hi guys! Well there is some evolution science I wanted to talk about, the evolution of flowers! Something about the evolution of flowers boggles my mind.

For one thing, how crazy is it that the male part of the flower, actually is "male" looking. Its the longer, skinnier part. Just like in animals, its the male part that contains the 1000s or millions of pollen that go into the female part (what we call sex). And the female part, just like in animals, contains the seeds, aka as eggs in animals. Same concept. These seeds, then develop in the ovary. A fruit is literally a swollen ovary - mmm! Tasty pregnant plant parts.

Okay, so its crazy and weird how flower sex has evolved to be so animal like.

But thats not even the craziest part. No, what's crazy is that both trees, grasses and everything else in between grow flowers that function in the same exact manner. Why is that weird? Because flowering grasses (as far as I know) did NOT evolve from flowering trees. But they both have flowers.

Divergent evolution ftw! But this is some extremely precise divergent evolution. Im reading that the same type of genes that mutated a leaf into a flower, were used by all flowering plants. And considering that a flower functions the same on a tree as it does on a grass, doesn't that mean the mutation that occurred in the tree is the same kind of mutation that occurred in the grass?

Doesn't this suggest that not all mutations are "random"? Maybe its random when they happen. But the result isn't so random. At least, not in flowers!

It seems like to me, that the mutations of flowers is a potential in a certain set of genes. Billions of years from now, some other non-flowering plant can mutate those same genes and get a flower that works just like any flower today! That's pretty incredible, and I think it says a lot about evolution as a whole.

^ That is mind boggling, isn't it? I think the answer is natural selection. There are many many random mutations, but only certain kinds will actually produce offspring that are fully functional and also better adapted to survive and pass on their genes, so those are the ones that flourish while the rest can't compete, and get squeezed out. So apparently those mutations that happen to take best advantage of the way nature works are the ones that flourish.

:breakitdown::banana::cheers::rockon::yddd::muffin ::dancingcow::awesomed::bender::giraffe::clap:

I was about to post here to celebrate the news posted by Box77 on a now locked thread that England has cast out Creationism from the public schools!! So excellent!! And yet the question remains, why did it take so damn long? But at least it's finally happened - we can all breathe a bit easier and hope that America soon follows suit (though it's up against much stiffer competition here of course).

Hip Hip HOOORAY!!!!

:breakitdown::banana::cheers::rockon::yddd::muffin ::dancingcow::awesomed::bender::giraffe::clap:

I think you mean convergent evolution there, not divergent, Juroara but pedantry aside, that is pretty awesome stuff.
Another rather newly discovered example is that of caffeine. After sequencing the coffee plant's genome it is now known that caffeine has been independently evolved by the coffee, tea and cocoa plants. The buzz is just that great a sell for potential pollinators such as ourselves!

Coffee genome sheds light on the evolution of caffeine

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Originally Posted by juroara

For one thing, how crazy is it that the male part of the flower, actually is "male" looking. Its the longer, skinnier part. Just like in animals, its the male part that contains the 1000s or millions of pollen that go into the female part (what we call sex). And the female part, just like in animals, contains the seeds, aka as eggs in animals. Same concept. These seeds, then develop in the ovary. A fruit is literally a swollen ovary - mmm! Tasty pregnant plant parts.

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The anthers (the male reproductive parts of flowers) never go into the stigma/style (female reproductive parts). Pollination by other creatures (like bees) is how plants most commonly reproduce. The reason for anthers being long and skinny is probably so that they're more accessible to pollinating organisms. Also, the ovaries contain ovules which only become seeds after fertilization.

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But thats not even the craziest part. No, what's crazy is that both trees, grasses and everything else in between grow flowers that function in the same exact manner. Why is that weird? Because flowering grasses (as far as I know) did NOT evolve from flowering trees. But they both have flowers.

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Trees are gymnosperms, so they don't have flowers.

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Doesn't this suggest that not all mutations are "random"? Maybe its random when they happen. But the result isn't so random. At least, not in flowers!

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The mutation is random, but the survival of the trait isn't.

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Originally Posted by BLUELINE976

The anthers (the male reproductive parts of flowers) never go into the stigma/style (female reproductive parts). Pollination by other creatures (like bees) is how plants most commonly reproduce. The reason for anthers being long and skinny is probably so that they're more accessible to pollinating organisms. Also, the ovaries contain ovules which only become seeds after fertilization.

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Hey, come on man! Stop crushing the fantasies of flora fetishists.

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Originally Posted by BLUELINE976

Trees are gymnosperms, so they don't have flowers.

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o_O what is that tall woody thing outside my house growing flowers?

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Originally Posted by juroara

o_O what is that tall woody thing outside my house growing flowers?

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He means flowers with the purpose of reproduction, I think. Trees bear fruit that protect their seeds and are carried around by animals, increasing the distance the seeds are spread. The tree does not rely on pollination to reproduce.

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Originally Posted by juroara

o_O what is that tall woody thing outside my house growing flowers?

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It's for sexual reproduction Ma'm. Just ignore it. :paranoid:

Excuse me blueline, but I think you are mistaking tree vs coniferophyta there?

Trees that come from gymnosperms include conyferophyta and cycada, right? Although the latter is mostly confused with palm trees, due to their very similar outward structure. And then there are several kind of trees that come from angiosperms such as the apple tree from the rosaceae family.

So all angiosperms have flowers, but not all trees are angiosperms. This is another thing plants do weirdly, the whole wood-structure.

And then, mentioning flowers it is also awesome how Ephedra (From Gnetidae) is starting to grow flower-like structures much like the ones in angiosperms yet different. There is even double fertilization present in them, but the process is different too! So yes this further proves that as much as mutations occour randomly they are not chosen randomly. Guess insects now have a patent on plant evolution and flower-like things are at the top of their list... not like humans don't love ephedra obviously.

Yep, my mistake. Gen Bio II was a while ago and I didn't pay much attention to the botany section. I was thinking of conifers.

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Originally Posted by BLUELINE976

Yep, my mistake. Gen Bio II was a while ago and I didn't pay much attention to the botany section. I was thinking of conifers.

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Recognizing own mistakes, that's an example to follow!

I was wondering about the mechanism that works inside a seed once it gets in a proper place to start a new specimen, etc. but all I was able to find was sort of "miraculous" explanations. Does anyone know any accessible source where I could find more scientific information about the process of germination?

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Originally Posted by Box77

Recognizing own mistakes, that's an example to follow!

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Agreed, it's a shame really that Deanstar was a troll so he was never able to do anything like that and actually earn some respect around here despite his beliefs. If he, by some stretch of the imagination, wasn't actually a troll, I think I would feel sorry for the guy. It's hard to come across people that unapologetically ignorant these days. Bah, who am I kidding? Still, it's really kind of depressing that people like him not only exist but make up the majority of the people on the planet. :blue:

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Originally Posted by snoop

Still, it's really kind of depressing that people like him not only exist but make up the majority of the people on the planet. :blue:

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I personally think that most people don't have that strong of an opinion about the origins of life in a scientific context. Only well nourished and safe people have the luxury to practice militant ignorance like Mr. Star. Your average Sub-Saharan African for example could give less than two shits. If that's what the curriculum that is going to lift them out of poverty says, they will follow it.

Being schooled is a sign of privilege over there, no one would take it for granted like creationists do in the west.

There's no denying that, but they are still ignorant whether the circumstances of their ignorance are out of choice or not. Many of them would surely be just as unapologetically ignorant if given the chance to be as educated as possible. To try and remain truly open minded and willing to accept when you are wrong and learn from it is a very rare quality that many are all too happy to throw away. That, or they are simply incapable of critical thinking and not just believing that they are right and know everything after becoming a teenager (that's when children stop asking questions and believe they know everything). It's more or less human nature, it seems. If it weren't we wouldn't still be fighting wars the way we are, and we wouldn't allow big corporations to run our government and stifle human growth and progress as a society. In third world countries we wouldn't see so much poverty or children being forced to become part of the military. An overwhelming majority of people just don't want to critically analyze things and do what's smart and makes sense. Instead they'd rather fight, believe in things like ghosts and magick and psychic powers, and that dreams are different realms or dimensions or real places you go to at night, or that a man in the sky made the Earth 6000 years ago and that evolution is a fraud. It doesn't matter about your socioeconomic status or if you aren't even living in a place where economics is a thing, people are just too ready to believe out-and-out bullshit be it for confirmation bias, fear, or plain fantasy.

Well, you are equivocating two things there, Snoop (Lion?):
being educated about evolution and being educated in general. You may feel that that people would "surely" chose to be ignorant over being educated but that's not what the evidence shows. Given the chance, most people will chose to be educated. Culturally, many countries highly value studiousness more than the Americans.

There are reasons for why lay people are sceptical about evolution beyond simply ignorance and religious motivations. With a theory like Newton's laws of motion, the inferential gap between that and basic algebra is vanishingly small. As a result, most people would not go around loudly proclaiming his ideas as brainwashed babble. However, with a theory like evolution, there is a far larger inferential gap, a gap that I do not feel many scientists appreciate. To believe in it, you need to take on board several other ideas.

You would need to know why scientists believe the earth is nearly 5 billion years old for example which would in turn require at least a basic understanding of geology and radioactivity. You would also need to understand concepts like genetics at least to a basic Mendelevium level and how traits inherit through generations. If you are more naturally critical, you would probably also require knowledge of the chemistry of life which in itself requires several inferential gaps.

Most believers in natural selection do not in fact understand all of the above. Their knowledge is surface deep and the rest they just take on faith. There is nothing necessarily wrong with that. After all, our time on earth is finite (at least until we finally crack immortality in the next 30 to 60 years) so we cannot sit down and assimilate all the information required to get from first principles to evolution.

However, if you are from a background that has either never appreciated scientists or have a natural mistrust for them (some of which is justified in select circumstances), you are not going to do that. In order to be convinced, someone will have to begin from the very bottom and work upwards. Most people and even scientists are not qualified or interested enough in all those steps and will likely become quickly exasperated with the creationist and dismiss their doubts as simple stupidity.

So now you have a lay person who feels his doubts marginalised. He then hears the words of some creationist who parrots back his doubts to him. He feels validated and drawn in. After all, this creationist guy seems respectable. He uses eloquent language, wears a suit and is a spiritual man. At that point, the creationist sect have a new devoted convert.

Of course, you are absolutely correct that we have a series of naturally evolved heuristics that render us susceptible to biased thinking. However, this is not our fault and hopefully we can update our hardware in the near future to eliminate these bugs. In the meantime we can in fact overcome base human nature with sufficient diligence.

Buddhist practices, the scientific method and the enlightenment are all totems to our fight against our own hardwired stupidity.

I'm interested by the fact that (speaking in broad generalities) many conservatives tend to be fundamentalist Christians, and some are Creationists, and while most liberals adhere strongly to evolution and climate change and to support science in general, many of them are into really esoteric spiritual beliefs and things like solipsism. You know, psychic powers, dreams are really other worlds we visit, that kind of stuff. Of course both groups also have plenty of level headed people free of anti-rational belief systems. Apparently libertarians tend to largely believe that there is an objective reality and that we are capable of perceiving it pretty much as it really is, with of course some wiggle room for various distortions here and there. I suspect a lot of moderates fall into that camp as well.

This gets interesting when you add in the general types of government each group favors (again, totally broad generalities of course) - the hardcore religious fanatics tend to want fascistic governments that push traditionalism, the (radical) leftists tend to want socialism and communism (hippie communes etc) which historically always result in fascistic welfare police states based on taking from the wealthy to give to the poor. The ones who don't fall into either wing or subscribe to anti-rational belief systems tend to favor small government and freedom.

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Originally Posted by Darkmatters

the (radical) leftists tend to want socialism and communism (hippie communes etc) which historically always result in fascistic welfare police states based on taking from the wealthy to give to the poor. The ones who don't fall into either wing or subscribe to anti-rational belief systems tend to favor small government and freedom.

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I agree with much you say but a challenge that I have not seen libertarians answer to is the example of European countries like the Netherlands with socialist government policies yet have better individual freedoms and standards of living then pretty much the rest of the world. Also people like Glenn Beck fall under the wings of libertarianism yet to call him a rationalist would be laughable.

Ha!
I'm really no fan of locked threads usually - but that one - ha!
My fever's gone - immune system vs. bug 1:0 to me - and I'm quite happy not to be in some way feeling I needed to follow through now with my announcements and try for the umpteenth time to run with my head first against a supernaturally thick brick wall.
That was a real wall, though, not a trollish one would be my assessment, sort of scary...

Juroara - I read a fascinating book called "Why We Get Sick" by Randolph M. Nesse - that's about evolutionary medicine, or rather looking at human biology, psychology and pathology through an evolutionary lens. It has very interesting information, but also great educated speculations - for example on the origins of sex.

Drawing on my "education" - if you take bacteria - some of them can also exchange genetic information, little rings of DNA called plasmids, by something called "sex-pili". Some bacteria can connect by making a little tube between them and then inject that information over to the next one - in that way they can gain for example resistance to antibiotics, which is not so nice. That's not sex, though.
Dayam - I needed to look it up again, I'm afraid - but they go from there and then say something like that for an organism to take on genetic information is less desirable than giving it out to others and so on and so forth...
Well - I'm still a bit deranged - that's not really going anywhere before I take up the book once more and this time with exporting quotes - soz.
But this thread is a great motivation to actually do that, to start out with my planned system of reference keeping from books I read on Kindle...
It doesn't explain evolution to doubters and/or the really uninformed, well a bit, but it's really more about teaching what is not so widely known, even among physicians, but it's written so that it is well understandable for non-physicians too, and making suggestions for further research to check up on tons of very reasonable speculations. I got it because Dawkins had recommended it - and it was the most thought-provoking and fascinating thing I read in a long while.

Okay - next try - convergent evolution - the eye has evolved several times over independently on this planet, and one can be reasonably sure, that aliens in an environment with light will look back at us with some sort of eye, if we come to meet them!
Watch this whoever fancies such things:

https://www.youtube.com/watch?v=NqArGW6k5gc

It's about alien life in general - but very much about convergent evolution on our planet, like the different sorts of eyes we have here, and how one can speculate, that very similar features up to actually the same ones, construction-wise, would be selected for by means of the characteristics of the environment, which of course boils down to basic physics and chemistry, and those are the same all over our universe.
Enjoy!
:alien:


Ah - something else - been just thinking about that alien smiley, and how it is green, and how that could be a good guess at an alien's colour, and how we even have an animal on our planet, which can actually do photosynthesis:

http://www.dreamviews.com/science-ma...ld-elysia.html

http://lh3.googleusercontent.com/-KP...fsdfsdfsdf.jpg

^ (@ Deviant)Remember there are a lot of people claiming to be libertarians who really aren't. Plus it's an umbrella term covering a few different positions, with some leaning right and some left (it doesn't allow for anyone who leans the way Beck does though :cackle: )

And of course the Netherlands - that's not a full-on socialist country, more of a social democracy. I've heard arguments on both sides for social democracies - usually it's the socialists who claim they're utopias, while some people say that's not even close to true. I guess it depends on who you are and what your stance on personal liberty is. Many people believe we need to give government lots of power and give up our liberties to it in order to be protected. Of course once you do that, you have no protection from the government! Give them a certain amount of power and they'll only want more, and when they have enough power, then there's nothing to stop them from suddenly just taking it all. I think it takes a certain kind of person to want that - someone who doesn't feel capable of protecting themselves, and is extremely trusting that power doesn't corrupt. I've heard that the various halfway socialisms have a way of just being temporary, and once you start down that slippery slope you'll end up full-on socialist eventually. Not sure if that's true.

And welcome back to the land of the living Steph!! It's good to have you among us again!

Good to see you back, Steph! I find bacteria communities fascinating, especially the way they have their own forms of cross genetic mixing like our own sexual ones. Bacterial diversity is in the metabolism and not the shapes. I often wonder if there are selection pressures out there that could cause bacteria to evolve a collective intelligence. Not quite multicellular but rather a culture.

I agree with you Mr Matter that pure socialism is not the way to go but I do not think libertarianism in it's purest form is a realistic form of governance either. It assumes that humans are far more trustworthy than they really are. I think there has to be some kind of societal framework to keep individuals from asserting dominance over others. The only question is what sort of framework and how much power should be given to it. There are certainly many compelling arguments for deregulation the libertarian employs such as the fact that the FDA leads to far more deaths from delayed acceptance of treatments than it saves in preventing faulty ones.

However, this is very off-topic. I think we should have a more specialized thread for this, perhaps in the philosophy sub-forum. Sorry for this lengthy digression, Steph.

I don't know why every time it comes in words of philosophy I tend to 'empty' read it. Just like looking through the paper (LCD) without making any neural connection - Duh! I think I didn't learn to pay attention enough when reading something. :chuckle: and my language teacher thought I was the best in the class just because of I fluently read the texts!! Bad move Mrs. Hope...

Perhaps there should be a philosophical branch called something like Monetarilism (or something like that if you get it), where the main purpose of life is getting money no matter what you think, which is how I see humans all around the world. Whatever you say or do, whatever you think, no matter where you come from, believe in god or not, you always will need money to live. Work for it, ask for it, steal it, do whatever you want to get it, but without it, you won't get too far unless you live in some isolated place on earth where it's still used sea shells to exchange your goods.

It's a shame to see all the contradictions of people claiming one thing and doing exactly the opposite just to get their pockets charged to pay the bills. Like those punk rockers holding beers and smoking their purchased stuff singing about poverty and how unfair life is. Or all that theater apologizing for the victims of the holocaust every year as a ritual since the first German politician (sorry, I'm not good remembering names and don't find it in Google) did it back in the days when the war was over. I don't remember any Spanish king doing the same for the enormous amount of people killed when conquering the new world, not taking into account the cultural disaster that it meant for mankind! Well, perhaps it's because America (North, Center and South) was just that, the source to save their crackled economy. I think it was just a Ska-punk band who apologized for that catastrophe around 2008 in their tour around the south of that continent but I don't really know, may be I didn't read enough (or didn't pay attention to what I read ;-)) to know there's a memorial for all the natives who lost everything, including their life... but, so is evolution, anything but fair.

Quote:

---

Originally Posted by DeviantThinker

I agree with you Mr Matter that pure socialism is not the way to go but I do not think libertarianism in it's purest form is a realistic form of governance either. It assumes that humans are far more trustworthy than they really are. I think there has to be some kind of societal framework to keep individuals from asserting dominance over others. The only question is what sort of framework and how much power should be given to it. There are certainly many compelling arguments for deregulation the libertarian employs such as the fact that the FDA leads to far more deaths from delayed acceptance of treatments than it saves in preventing faulty ones.

However, this is very off-topic. I think we should have a more specialized thread for this, perhaps in the philosophy sub-forum. Sorry for this lengthy digression, Steph.

---

I have no problem with my thread delving slightly off topic - I think often requiring threads to stay strictly on topic kills the organic nature of human thought and conversation, which tends to need to delve into detours in order to discuss the origins of ideas - like for instance the type of mentalities that insist on disbelieving evolution or other aspects of science.

I don't consider myself a hard libertarian - that sounds a bit scary to me! I'm more attracted to classical liberalism, which is essentially what was laid down by the founding fathers in the constitution to begin with. Not "no government" but a small government with checks and balances to keep it from amassing too much power and from getting involved in our lives too much. Classical liberalism is one of the branches of libertarianism. And actually I would say the opposite of what you did here - "I do not think libertarianism in it's purest form is a realistic form of governance either. It assumes that humans are far more trustworthy than they really are".

I say that allowing a government as centralized and controlling as what we have now is putting too much trust in people. In the ones in charge to be specific. Government tends toward incompetence and often to corruption, and the people who are drawn to power are often corrupt people. Government's job should be to protect our liberties, not to find ways to violate them.

You also said - "I think there has to be some kind of societal framework to keep individuals from asserting dominance over others." Exactly. Like the kind of dominance government has assumed. How can we get them to relax their death grip on their own power? As Benjamin Franklin said, “Those who would give up Essential Liberty, to purchase a little Temporary Safety, deserve neither Liberty nor Safety".

I should add that many of these ideas are brand new to me and the reason I bring them up in here is in hopes that I will hear from some people with different takes on it, so I can learn more. While one of my main sources claims to be libertarian, I suspect he might actually be right wing, and I'm trying to separate the two belief systems.

But yeah, I don't mean for this to become a major part of the conversation here - just wanted to respond to that.

Ok, I guess it's my job now to bring it back on topic…

Steph, that is really bizarre and fascinating, an animal that does photosynthesis?? And I'm actually being completely serious - not just trying to get back on topic. That is a bit of a mind blower!! so far the most alien creatures we've discovered are those that exist deep in our own oceans. Here we are, trying to explore outer space, when we have yet to understand many aspects of our own planet!

I've just found this one recently uploaded on the web showing evolution for kids... and some grow people who don't clearly understand:

https://www.youtube.com/watch?v=lIEoO5KdPvg

Found something again: Spectacular Genetic Anomaly Results in Butterflies with Male and Female Wings | Colossal
Not exactly evolution but genetic caprice, which should fit as well:

http://www.thisiscolossal.com/wp-con...utterfly-1.jpg

http://www.thisiscolossal.com/wp-con...utterfly-4.jpg

http://www.thisiscolossal.com/wp-con...utterfly-5.jpg

http://www.thisiscolossal.com/wp-con...utterfly-6.jpg

"In the realm of genetic anomalies found in living organisms perhaps none is more visually striking than bilateral gynandromorphism, a condition where an animal or insect contains both male and female characteristics, evenly split, right down the middle.
This condition is rare, but not unique. It's been spotted in birds, insects and crustaceans all around the world. It's unheard of in humans and it's thought that it occurs differently in each of the groups listed above.

http://i1339.photobucket.com/albums/...pse8c69245.jpg

In insects the mechanism is fairly well understood. A fly with XX chromosomes will be a female. However, an embryo that loses a Y chromosome still develops into what looks like an adult male, although it will be sterile. It's thought that bilateral gynandromorphism occurs when two sperm enter an egg. One of those sperm fuses with the nucleus of the egg and a female insect develops. The other sperm develops without another set of chromosomes within the same egg. Both a male and a female insect develop within the same body.

There are several theories as to how this can occur in other animals, like birds. Some have suggested that these bilateral gynandromorphs are chimeras, where two separate embryos fuse together early in development - essentially the opposite of identical twins, where one embryo separates into two. Another hypothesis is that gynandromorphism in birds occurs when the sex chromosomes are unable to separate in the first cell division after fertilization. Others suggest that the error occurs in the formation of the egg itself, with an egg accidentally ending up carrying two chromosomes, one of each sex, rather than the single chromosome it should possess. If an egg like this was fertilized by two sperm the resulting embryo would contain some ZZ cells and some ZW cells (female birds have ZW chromosomes and males have ZZ).

Ggynandromorphism doesn't always look so perfect. Sometimes animals can possess a strange patchwork of different cells all across their bodies - it can even occur within a single feather. But sometimes, like in the butterfly above, bilateral gynandromorphism occurs and you see this perfect division between the two halves of the body."

These would make for a great Christmas present I'd say...:wink:

http://thisiscolossal.com/wp-content...7/eraser-1.jpg
http://thisiscolossal.com/wp-content...-2-600x323.jpg

These evolution erasers were designed by Hiroyuki Shiratori for Japanese product design label h concept. Shaped like a person on one side and an ape on the other, the eraser gradually changes form (evolves!) with regular usage. Although not for sale yet, according to Johnny at Spoon and Tamago, you can request to purchase one.

I just love it...

https://www.youtube.com/watch?v=xdWLhXi24Mo