When this C became available in the diet, omnivores that ingested this C no longer needed to systemically produce C and natural selection caused this mutation. And in what organisms would this environment have selected for? ALL of them, people, chimps, gorillas, little funky tree monkeys, little monkin' tree.........So you are quite surprised to see this mutation in common with primates?
Stop it, Jerry, you're killin' me here! I haven't laughed like this for months.
Yes, of course it's not surprising ... but you forgotr to mention that other omnivores such as pigs, chickens, and raccoons do synthesize vitamin C. So the fact that one subset of omnivores, within which we find literally thousands of strtiking similarities, shares this exact mutation (when we know that there is at least one other mutation that would knock out vitamin C, and there's probably hundreds or thousands that would) is not surprising at all; it's only yet another comfirmation (albeit a dramatic and easily understood one) of common descent among primates. Like us.
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