Evolution - small to big?

I hope to get back to this topic later, with further comments, but for now I'll pick on a Crashfrog message a bit.I (even as a non-biologist) strongly suspect that Crash's science in the message this is a reply to, is seriously flawed.

quote:

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Here's an experiment you could do. Take some animals and raise them in oxygen tents of various concentration. Try and grow giant animals.

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I think this statement is much akin to if a creationist made the challenge "Put a reptile into a laboratory, and induce it to evolve into a mammal". Evolution does not happen like that, in such a short time frame.I suspect that higher oxygen concentrations, over a geologicly long time period, could be an aid to the evolution of larger life forms. I now drop this concept into the laps of the biologists present.I intend to get back to the history of oxygen concentration variations over geologic time, and the possible relationship to life form evolution, in a later message.Cheers,
Moose

While Crashfrog may not be wrong, I find his argument to be significantly flawed by incompleteness.Regardless of what the YEC perspective is, the evolution perspective is that the large animals became large animals through evolutionary processes - a response to a change in environment. I think that a higher atmospheric oxygen concentration may sometimes have been a significant factor in the changing environment.Moose

To me, message 1 sure seems to be from an old earth evolution perspective. Message 2 falls under the influence of Carl Baugh, with a vague hint of a YEC perspective.I see the topic as a whole, as being one of old earth evolution.Moose

I have been trying to find some info, on the variation of atmospheric oxygen content through geologic time - not much sucess.The below cited is something I did find.
http://www.sciencedaily.com/...ases/2000/03/000308081611.htmI have been speculating that there was a significant rise in atmospheric oxygen during the Mesozoic (aka "Age of Dinosaurs"). Part of this line of thought was the prominent existance of coal created in the Carboniforous (sp?) period of the late Paleozoic. I was thinking that the great removial and burial of carbon might result in higher atmospheric oxygen levels.Of course, the Mesozoic "Age of Giants" was preceded by the great extinction at the end of the Paleozoic.Mostly just some speculations on my part. I haven't been able to track down much at all in good specific information.I do suspect that the Triassic and/or Jurassic did have higher oxygen concentrations, but again I concede not having tracked down supporting information.I might be babbling,
Moose