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Anything can evolve into anything.

Discussion of everything related to the Theory of Evolution.

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Anything can evolve into anything.

Postby SelfishGene » Fri Nov 19, 2010 6:31 am

Anything can evolve into anything.

The statement sounds laughable, but it's worth recognizing that in principal it is a true statement. Pick any two organisms on the evolutionary tree of life (ancestral or modern), and there were always be transitional forms leading from one to the other. Dawkins explains this in the first chapter of The Extended Phenotype:

Consider another thought experiment, this time from evolutionary biology. When I was an undergraduate obliged to write speculative essays on 'the origin of the Chordates' and other topics of remote phylogeny, one of my tutors rightly tried to shake my faith in the value of such speculations by suggesting that anything could, in principle, evolve into anything else. Even insects could evolve into mammals, if only the right sequence of selection pressures were provided in the right order. At the time, as most zoologists would, I dismissed the idea as obvious nonsense, and I still, of course, don't believe that the right sequence ofselection pressures ever would be provided. Nor did my tutor. But as far as the principle is concerned, a simple thought experiment shows it to be nearly incontrovertible. We need only prove that there exists a continuous series of small steps leading from an insect, say a stag beetle, to a mammal, say a stag. By this I mean that, starting with the beetle, we could lay out a sequence of hypothetical animals, each one as similar to the previous member of the series as a pair of brothers might be, and the sequence would culminate in a red deer stag.


Just something interesting I thought I'd point out. Your comments/criticisms are welcome.
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Postby enarees » Fri Nov 19, 2010 2:58 pm

Our genes may give rise to a number of simpler organisms.
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Re:

Postby canalon » Fri Nov 19, 2010 3:24 pm

enarees wrote:Our genes may give rise to a number of simpler organisms.

Your point is? In fact, no, please do not answer, your fantasy are neither informative, interested, or based in anything that look like science. So please STFU.


In response to the OP,
I guess the lecturer has a point, one can imagine that it is theoretically possible. However, when on start to imagine the number of gene replications, duplication, loss and acquisition by horizontal genetic transfer that would be necessary, and the odds associated to get a specific (set of) gene in response to a given selective pressure, the possibility is quite microscopic.
As S.J. Gould pointed in one of his essays, if there was a way to rewind the story of life to replay it, the outcome would be radically different each and every time. There is often more than one "good" reaction to a given evolutionary pressure, and the one(s) that prevails are not necessarily the best in an absolute way, just the one that were lucky enough to be selected for.
And I think that Dawkins' tutor hypothetical case is not much more than just mental masturbation, without much significance in term of evolutionary biology.
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Science has proof without any certainty. Creationists have certainty without
any proof. (Ashley Montague)
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