Comment: If you think Darwin's theory

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If you think Darwin's theory

was that every species on some mythical continuum from "lowest" to "highest" is marching resolutely up the "evolutionary ladder" to become human, then I'd say you you don't understand the theory. I know you didn't say this above but it's a common mistaken belief and something in what you said made me think that's what you thought. (Apologies if I'm wrong.)

Evolution entails the survival or rejection of certain traits, including mutations caused by chemicals or radiation particles, in a species population based on the advantage or disadvantage they give an individual in parenting offspring. The more success a trait lends, the more it spreads in the gene pool. The whiter in winter the snowshoe hare or the lizard in the White Sands of New Mexico, the better it evades predators.

Over time, Darwin says, cumulative advantageous changes in one geographic part of the population make it too different to interbreed with another portion of the population to which it once belonged. Further such changes over time warrant assignment to a different genus, then taxonomic tribe, then subfamily, then family, then superfamily, etc.

It is the amount of accumulated change, not some supposed "advancement up the ladder" that is the result of evolution.

You may have heard that "nature abhors a vacuum." What that means is that any time there is an unexploited niche (food source or territory, even in a hostile environment) some creatures will begin to exploit it and those individuals that are most successful at it due to longer fur, longer legs, smaller size, better coloration, etc., will better survive and pass those traits on to their offspring and eventually the entire gene pool that is operating in that mode. Many such changes in the gene pool make it at home in the new niche and also make it distinct from some larger population to which it once belonged.

It's true that there are organisms that appear not to have changed in 100-million years and more. (They probably did change somewhat, but not anatomically.) It proves one thing: They lived in a stable environment that lent no advantage to new traits or mutations. In other words, without an advantage awaiting it, a mutation will not expand in the gene pool.

Evolution produces a radiating out of species into all possible environments, not "advancement." Apes evolved because there was a niche awaiting large brachiators (creatures that can swing by their arms from tree limb to tree limb) with high intelligence.

Other apes began to forage in a niche with fewer trees and began to locomote more on their hind legs so they could see over the brush and tall grass, or so the speculation goes. In time they accumulated enough minor changes to make them distinct from the population they had once belonged to, one whose other portions may have remained in a stable arboreal environment and changed little over time. Bigger brained individuals may have had a further advantage to these erect-walking tribal hunter-apes while a bigger brain in a cebus monkey or horseshoe crab might be a hindrance.

If humans evolved naturally from apes (and I doubt they did), it was because there were survival advantages to them in becoming relatively hairless, becoming physically weaker but with finer motor coordination, developing bigger brains and smaller teeth, etc. It was not because of some presumed grand scheme of evolution to produce a human or because all species bear an inner drive to advance and become human. Even if there were such a drive to advance, it is not part of the theory of evolution.

New Hampshire and Ecuador.