Friday, February 1, 2013

If we evolved from monkeys...

"If we evolved from monkeys/apes why are there still monkeys/apes"

This is a study in how to clearly and boldly display that you are utterly ignorant about Evolution. No statement I'm aware of shows more blatant and willful ignorance than this one. You are like a peacock, showing off just how ignorant of the facts you are as if you are proud of being ignorant. Baffling. I mean, it's fine if you don't understand Evolution and don't take a position on it, it's when someone speaks publicly, as if one is an authority, that I take objection to it.

If you even remotely cared about the truth then you would do your due diligence and research such simple topics, but you clearly don't or you wouldn't have made such a statement.

Did it not even cross your seemingly vacuous mind that we DIDN'T evolve from modern monkeys, but rather from a distant common primate ancestor?

In fact, we have very good information about when each lineage split (but not perfect of course, exacting details are lost in the mists of time, but this doesn't mean that we cannot know anything about the subject).

For example, Homo sapiens and Pan troglodytes (modern chimpanzee, NOT the same as the common ancestor) last shared a common ancestor some 4.1 million years ago.

And if we consider the Pongo pygmaeus (modern orangutan, again, NOT the same as the common ancestor), the divergence is even greater, indicative of MUCH older last shared common ancestor some 14 million years ago.

What was that common ancestor? We don't know precisely what it was because 14 million years is a LOT of time and intelligent animals aren't fossilized as often as those that die in favorable sediments for fossilization. But we do have fossils that date from around these times and we believe (based on the evidence) that they would be the close cousins of the suspected common ancestor.

It would be ridiculous to expect to find, out of the billions of animals dead over millions of years, one that was EXACTLY in our lineage. Nor is such a thing necessary. They would be almost indistinguishable from the ones we do find. Some random person from Europe isn't your direct ancestor but they are still a Homo Sapien and their DNA is extremely close to yours. Now imagine that you find a European from 5000 years ago -- that's still close enough. Even human beings 100,000 years ago are anatomically modern Homo Sapiens, you have to look back deeper in time before you start seeing genetic variants that are different enough to warrant being categorized as a different species, 250,000 years is on the edge, 1 million years, 4 million years, 14 million years, 3.6 BILLION years -- these are the massive timescales where evolutionary changes accumulate to significant levels.

But for an example, one such species is Ardipithecus kadabba. We can tell from the remains that this was neither modern ape, chimp, or human - but rather has a blend of features that fit into the geological timescale in which it was found. Then there is Ardipithecus ramidus, and Australopithecus afarensis, and Australopithecus africanus, and Australopithecus anamensis, and Australopithecus garhi, Australopithecus sediba, and Homo erectus, and Homo floresiensis, and Homo habilis, and Homo heidelbergensis, and Homo neanderthalensis, and Homo rudolfensis, and Homo rudolfensis -- all different species that show the evolutionary changes from earlier primates to Homo sapiens.

Consider that, aside from beings a completely unique mix of alleles from your parents (DNA recombination during meiosis means that each chromosome you inherit aren't just a copy of one from one of the parents but a completely unique, sliced-and-diced random mix from both parents), you have about 150 mutational changes in your DNA as well. And that is multiplied by every organism in parallel over every generation (and the small animals had much shorter generation times, bacteria have generations measured in hours and there are an estimated five million trillion trillion bacteria on the earth - that is an unimaginable amount of mutational change every minute, not to mention over 3.6 billion years).

Most mutational changes are neutral, neither harmful nor helpful (or at least extremely subtle). Extremely harmful mutations result in either an nonviable gamete or zygote, by some estimates 40-50% of all fertilizations are unviable and produce natural miscarriages. The moderately harmful mutations that aren't fatal, are evident in our population as diseases. Slightly harmful mutations might be carried in populations for thousands of years, some of these (eg, sickle cell) even prove to have benefits that cause them to spread in populations despite their harmful "side-effects" (really there are only affects, side-effect is a misnomer based on a bias of what is 'beneficial' and what isn't). And occasionally, a mutation will prove beneficial such as Escherichia coli evolving the genes necessary to process Citrate (which actually depended on several independent mutational changes which were EXACTLY identified in the research). Some are mutations are morphological, some affect protein expression, some affect only the timing of expression (especially evident in the HOX gene complex).

And in light of all of that you expect to be taken seriously when you say something utterly devoid of reflective thought like "If we evolved from monkeys why are there still monkeys"?

Have some pride and educate yourself.

See Also: Evolution: As Simple As Possible, and the Rational Wiki response.

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