More evidence of macro-evolution.
http://news.yahoo.com/s/ap/20060616/ap_on_...zkxBHNlYwN0bQ--
Printable View
More evidence of macro-evolution.
http://news.yahoo.com/s/ap/20060616/ap_on_...zkxBHNlYwN0bQ--
Okay... I'll ask... what is the distinction between just plain old 'evolution' and 'macro-evolution'? and then, what do very long dead ducks have to do with it?Quote:
Originally posted by bradybaker
More evidence of macro-evolution.
http://news.yahoo.com/s/ap/20060616/ap_on_...zkxBHNlYwN0bQ--
Macro evolution describes the processes involved in the development of new species. For example, dinosaurs into birds. Micro evolution on the other hand deals with changes within a species. For example, Darwin's birds on the Galapagos Islands.Quote:
Originally posted by Leo Volont
Okay... I'll ask... what is the distinction between just plain old 'evolution' and 'macro-evolution'? * and then, what do very long dead ducks have to do with it?
One of the most common 'arguments' against macro evolution is the lack of a complete fossil record showing clear transition fossils. The very long dead ducks are an example of such a transition fossil, showing a clear link between ancient and modern species of birds.
Oh... okay... I get it. Learn something new everyday.Quote:
Originally posted by bradybaker
Macro evolution describes the processes involved in the development of new species. For example, dinosaurs into birds. Micro evolution on the other hand deals with changes within a species. For example, Darwin's birds on the Galapagos Islands.
One of the most common 'arguments' against macro evolution is the lack of a complete fossil record showing clear transition fossils. The very long dead ducks are an example of such a transition fossil, showing a clear link between ancient and modern species of birds.
Hmmmm... don't be surprised if next week I write an essay on the subject...
I have been in some lengthy discussions about this.
The information was just intuitive in nature. My argument has no scientific evidence to back it up. But I have not looked either.
This macro evolution being about as close that I have seen.
We all see evolution as something that takes a considerable amount of time. But regardless of how long something takes there still HAS to be minuscule changes during this long duration.
So how miniscule. How small?
Does our sperm change over the coarse of one man's lifetime?
It may sound absurd. But there has to be genetic changes and alteration at some small level
But a time line has to be drawn somewhere. Where does the beginning of the evolutionary process begin?
[quote]We all see evolution as something that takes a considerable amount of time. But regardless of how long something takes there still HAS to be minuscule changes during this long duration.
So how miniscule. How small?
Does our sperm change over the coarse of one man's lifetime?
It may sound absurd. But there has to be genetic changes and alteration at some small level
But a time line has to be drawn somewhere. Where does the beginning of the evolutionary process begin?
An individual does not genetically mutate during the course of its lifetime - the DNA with which it was born is the DNA with which it will die (barring a strong external forcing mechanism such as exposure to dangerous radiation, etc). However, there certainly can be, and are, small genetic changes which occur between two generations as the parental DNA combines to form that of its offspring. When discussing macro-evolution, the question of where to speciate an evolving population has some fairly complicated answers. A common and simplified rule-of-thumb is that a population has evolved into a separate species when it can no longer breed with an un-evolved population descended from a common ancestor (i.e. two separate species cannot interbreed). That's not a firm rule, though, since horses and donkeys can interbreed as can, apparently, grizzly bears and polar bears. There are other examples, as well, but if you're looking for a fairly good estimate, the "two species cannot interbreed" rule is accurate in most cases.
I think I have mutated a bit. :wink:Quote:
Originally posted by Peregrinus
An individual does not genetically mutate during the course of its lifetime - the DNA with which it was born is the DNA with which it will die (barring a strong external forcing mechanism such as exposure to dangerous radiation, etc). *However, there certainly can be, and are, small genetic changes which occur between two generations as the parental DNA combines to form that of its offspring. *When discussing macro-evolution, the question of where to speciate an evolving population has some fairly complicated answers. *A common and simplified rule-of-thumb is that a population has evolved into a separate species when it can no longer breed with an un-evolved population descended from a common ancestor (i.e. two separate species cannot interbreed). *That's not a firm rule, though, since horses and donkeys can interbreed as can, apparently, grizzly bears and polar bears. *There are other examples, as well, but if you're looking for a fairly good estimate, the "two species cannot interbreed" rule is accurate in most cases.
No. That makes complete sense. To combine two genes would be an obvious short term change in offspring.
So in theory just as the rich get richer and the poor get poorer wouldn't stand to reason that the smart would get smarter and the dumber stupidererer?
Let's face it, all men (And woman ) are not created equal. Therefore we get social classes of people that seem to grow apart.
I met a liger.
Your a freak. Those things are wierd.Quote:
Originally posted by Aquanina
I met a liger.
So to get this straight.
Your DNA is your DNA from start to finish regardless of anything. (except radiation and such)
Your own progression, diet, environment will NOT change the coarse of your DNA?
Why do certain diseases skip generations?
There is no smaller scale of evolution than the mating process?
Jeez! That's harsh. You call ME a freak just because I met a liger and you think ligers are weird? That was sort of a closed minded comment. Ligers are actually extremely cool. They look like giant tigers with lion colored skin.Quote:
Originally posted by Howetzer
Your a freak. Those things are wierd.
Yup. What you're born with is what you're stuck with (unless you want to expose yourself to gamma rays like the Hulk, but that's a bit of a gamble, really).Quote:
Originally posted by Howetzer
So to get this straight.
Your DNA is your DNA from start to finish regardless of anything. (except radiation and such)
Your own progression, diet, environment will NOT change the coarse of your DNA?
Well, I'm not a pathologist, but as far as I'm aware, no gene has yet been discovered which guarantees that a person who carries it will develop a certain genetic disease. Certain genes increase the likelihood that a person will develop a disease - it gives them a predisposition, but not a death sentence. Environmental factors (such as diet and exercise) are the other main influence on whether a person will develop a genetic disease.Quote:
Why do certain diseases skip generations? *
There is no smaller scale of evolution than the mating process?[/b]
And I'm with Nina on this one: ligers are very cool
http://www.sierrasafarizoo.com/images/animals/hobbs.jpg
How could you not like that? Badass and cute, both at the same time.
Woah.. I thought "liger" was a joke. What a cool lookin animal!
1. Recessive genesQuote:
Originally posted by Howetzer
1. Why do certain diseases skip generations? *
2. There is no smaller scale of evolution than the mating process?
2. Well... not everything mates. Mitosis only needs 1 organism, but the prinicple is the same: evolution isn't a concept to applied to a single organism, it is only meaningful when applied to populations of organisms.
[creationist]But now there's two more gaps lacking transitional fossils. :roll:Quote:
Originally posted by brady
One of the most common 'arguments' against macro evolution is the lack of a complete fossil record showing clear transition fossils. The very long dead ducks are an example of such a transition fossil, showing a clear link between ancient and modern species of birds.
-spoon
Quote:
Originally posted by Aquanina
Jeez! That's harsh. You call ME a freak just because I met a liger and you think ligers are weird? That was sort of a closed minded comment. Ligers are actually extremely cool. They look like giant tigers with lion colored skin.
ya ya. I know. I was jealous. So rather than explaining this deep rooted feeling of envy i just took the cowardly way out and called her a name. :PQuote:
And I'm with Nina on this one: ligers are very cool [/b]
Thats not true. Just like some genes will guarantee you have say blue eyes, others will guarantee that you will be born with a genetic disease. A lot of birth defects are caused by bad genes.Quote:
Originally posted by Peregrinus
Well, I'm not a pathologist, but as far as I'm aware, no gene has yet been discovered which guarantees that a person who carries it will develop a certain genetic disease. Certain genes increase the likelihood that a person will develop a disease - it gives them a predisposition, but not a death sentence.
Actually if you have the genes that causes a disease your pretty much guaranteed to get it. Now some might raise the risk to other diseases but the ones caused by bad genes your normally born with, or they could effect you later in life.
Since Howetzer was talking about diseases skipping generations and environmental causes of genetic diseases, the ones about which I was speaking in my above post were more along the lines of cancer, auto-immune diseases, and such, for which one can have a predisposition, but as yet, are not known to be caused exclusively by a gene or set of genes (not, for instance, Down’s Syndrome, congenital hypothyroidism, etc, for which we already have tests to isolate the causal gene(s)). However, looking over that post, I realize I didn’t specify that, so sorry for the misunderstanding.Quote:
Originally posted by Alric
Thats not true. Just like some genes will guarantee you have say blue eyes, others will guarantee that you will be born with a genetic disease. A lot of birth defects are caused by bad genes.
Some genes in certain species are just sitting as dormant until activated. An example is in many cats, the hair color on the ears will change from white to black depending on the temprature (black to absorb more heat in the winter). So the argument about being stuck with the DNA you have is true, however, it may be possible to 'turn on' certain genes using various stimulus, in order to adapt to new environments.
What do people think about the elephant population in Africa. Many elephants are now being born without tusks. Could this be called an example of evolution?
This change wouldn't happen during a single animal's lifetime... I'm pretty sure no animal has the ability to activate genes, no matter what the stimuli. What happens is the process of natural selection - in the colder climates, cats that have the gene for black hair on the ears are more successful and breed more etc etc. i think that's what you mean, isn't it?Quote:
Originally posted by PhowaBoy
Some genes in certain species are just sitting as dormant until activated. An example is in many cats, the hair color on the ears will change from white to black depending on the temprature (black to absorb more heat in the winter). So the argument about being stuck with the DNA you have is true, however, it may be possible to 'turn on' certain genes using various stimulus, in order to adapt to new environments.
As for the elephants, then yeah I guess it would be a process of natural selection, which if sustained long enough would give rise to evolutionary change.
No, I mean each season. Another exampe is rabbits fur. The genes code for brown fur in the summer when the weather is warm and the sunlight is plentiful, and then code for white (no color) when the weather is cold and the light is less plentiful. The rabit's DNA has codons that switch off and on adding the pigment to the fur folical in the summer.Quote:
Originally posted by Roller
This change wouldn't happen during a single animal's lifetime... I'm pretty sure no animal has the ability to activate genes, no matter what the stimuli. What happens is the process of natural selection - in the colder climates, cats that have the gene for black hair on the ears are more successful and breed more etc etc. i think that's what you mean, isn't it?
Nearly every animal on the planet has seasonal coats, humans included. Nothing special about that.Quote:
Originally posted by PhowaBoy
No, I mean each season. Another exampe is rabbits fur
PhowaBoy is definitely right here.
Another example; puberty. During the preteen years a gene is (naturally) activated that stimulates the production of various hormones (testosterone, estrogen, etc). This is an event that takes place naturally, but can be 'triggered' by certain outside stimuli.
It's not as if rabbits consciously activate brown fur, or humans decide to go into puberty. But it's still an example of activation/deactivation of genetic code.
EDIT: to be clear, the genetic material for such events is present at birth. When the gene is 'activated', this means that the DNA begins to be translated into RNA and then transcribed into proteins, which in turn do the work.
Actually I would say that 2 separate species certain can crossbreed, but it just does not happen very often in the natural world without intervention, probably I would say due more to different but similar species having different habits than it being a biological impossibility. But we crossbreed animals quite a bit; we crossbreed plant species all the time now, especially for industrial and commercial reasons; hell we've even crossbred plants with animals.Quote:
Originally posted by Peregrinus
(i.e. two separate species cannot interbreed). That's not a firm rule, though
Certainly.Quote:
Originally posted by dream-scape
Actually I would say that 2 separate species certain can crossbreed, but it just does not happen very often in the natural world without intervention, probably I would say due more to different but similar species having different habits than it being a biological impossibility. But we crossbreed animals quite a bit; we crossbreed plant species all the time now, especially for industrial and commercial reasons; hell we've even crossbred plants with animals.
Hence ligers, no?
A fundamental category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding.
Just like new breeds of dogs alpacas, lamas etc. But I think that gene code has have a specific attribute for this to happen. Like a man can't breed with an ape, even as close as we are in some genetic areas.
A shiatsu and a giraffe...Now that would be interesting
A giraffe masseuse?Quote:
Originally posted by Howetzer+--><div class='quotetop'>QUOTE(Howetzer)</div>And Tigons... don't forget about the tigons.Quote:
Hence ligers, no?[/b]
<!--QuoteBegin-Howetzer
A shiatsu and a giraffe...Now that would be interesting