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

    1. #26
      Member StephL's Avatar
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      Hach Xei!

      goodsigh2.gif

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


      Quote Originally Posted by Xei View Post
      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.
      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!

      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.
      Such lovely metaphors for our meta-featured mouse!

      Quote Originally Posted by Xei View Post
      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.
      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:



      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!





      Quote Originally Posted by Box77 View Post
      ^^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.
      Just saw that. For once I feel flattered that you use my threads in order to inform yourself!

      thank-you.gif

      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.

      Quote Originally Posted by Box77 View Post
      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.
      Could you please expound on this - are you talking about 'The Game'?
      Last edited by StephL; 06-16-2014 at 10:43 PM. Reason: can't seem to leave it be ..
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    2. #27
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      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! 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…

      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… )

      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.. )
      Last edited by Darkmatters; 06-17-2014 at 05:10 AM.
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    3. #28
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      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.
      Last edited by Darkmatters; 06-17-2014 at 05:25 AM.
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    4. #29
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      @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 ( 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.
      Last edited by Box77; 06-17-2014 at 01:27 PM.
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    5. #30
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      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.

    6. #31
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    7. #32
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      Quote Originally Posted by Darkmatters View Post

      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.
      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!

      Quote Originally Posted by Darkmatters View Post
      The main difference I can see between your description of what evolution is and Xei's is that I can understand his! 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…
      Pööh! biggrin.gif

      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!

      Quote Originally Posted by Darkmatters View Post
      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.
      Aand - another pöööh! That was "my tumour" which made you gag!! biggrin.gif

      Quote Originally Posted by Darkmatters View Post
      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… )

      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.. )
      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? biggrin.gif

      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..?


      Quote Originally Posted by Box77 View Post

      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.
      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!

      Quote Originally Posted by Box77 View Post
      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.
      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!!

      Last edited by StephL; 06-17-2014 at 02:24 PM. Reason: this and that and so forth ..
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    8. #33
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      Quote Originally Posted by StephL View Post
      Could you explain to me, what you mean with "ADN" please?
      DNA!!!!! Sorry, once again my language neural connections are playing those tricks on me... (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?
      Last edited by Box77; 06-17-2014 at 04:45 PM.
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    9. #34
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      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!
      But this here is much better in terms of entertainment and educationary experiences anyway!!

      Quote Originally Posted by Box77 View Post
      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?
      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!
      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.

    10. #35
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      Quote Originally Posted by StephL View Post
      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!
      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!



      Quote Originally Posted by StephL View Post
      Pööh! biggrin.gif

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


      Quote Originally Posted by StephL View Post
      Aand - another pöööh! That was "my tumour" which made you gag!! biggrin.gif
      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?


      Quote Originally Posted by StephL View Post
      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? biggrin.gif
      Haha… well, I'm not eating right now, and hopefully I won't think of that when I am..

      Quote Originally Posted by StephL View Post
      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..?
      Exploring the vast junkyard that is DNA (< mutant smilie)


      Quote Originally Posted by StephL View Post
      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!
      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.
      Last edited by Darkmatters; 06-17-2014 at 09:43 PM.
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    11. #36
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      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!

      tease (1).gif

      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:

    12. #37
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      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 ( 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
      Last edited by Box77; 06-18-2014 at 01:19 PM. Reason: trying to clarify...
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      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.

    14. #39
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      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:




      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:






      She doesn't look unhappy or tortured, now does she?
      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:




      Edit: 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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      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 ) 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 Originally Posted by StephL View Post
      I find this soo great, that you came to understand evolution thanks to this thread here - something your school failed to accomplish, Box!!
      Perhaps the best thing my school accomplish to do, was to get rid off me
      Last edited by Box77; 06-18-2014 at 07:29 PM. Reason: As usual
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      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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      ^^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.
      Last edited by Box77; 06-20-2014 at 07:32 AM.

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      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:

      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.



      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.
      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?

      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.
      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:

      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.”


      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 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.
      Thank you!

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

      Quote 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.
      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... biggrin.gif
      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

      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.
      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!
      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.

    19. #44
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      Quote Originally Posted by StephL View Post
      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.
      It's nice to see you again!! Welcome back!!

      Quote Originally Posted by StephL View Post
      Unfortunately one [of the two links] doesn’t work – the meteor one.
      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.

      Quote Originally Posted by StephL View Post
      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!
      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.

      Quote Originally Posted by StephL View Post
      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!
      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 (Was it the frontal lobe?) to produce awareness in dreams or so.

      Quote Originally Posted by StephL View Post
      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.
      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 , 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.

      Quote Originally Posted by StephL View Post
      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!
      Is it to lure in otherwise unwilling audience? Well maybe then that’s okay - or so.
      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
      Last edited by Box77; 06-27-2014 at 06:55 PM.
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    20. #45
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      Hi Box77!
      Thank you!
      smile.gif

      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...

    21. #46
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      ^^ 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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    22. #47
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      Quote Originally Posted by Box77 View Post
      ^^ 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
      Quote 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.
      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!!


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      Some funny maths

      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...
      Last edited by Box77; 06-30-2014 at 11:41 AM. Reason: English not my first language is
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    24. #49
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      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!

      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.
      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...

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      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!
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