In physical anthropology class years back, my professor was discussing the skull structure of Neanderthals, and specifically the occipital bun. She went on to discuss this being a marker of the species, and that it was exclusive to Neanderthals, I immediately raised my hand, and questioned, how her information was gathered on that particular subject, for I happened to have brought strong physical evidence with me that day to class to the contrary of what she was saying...my own skull, occipital bun included.
We discussed at fairly great length my hypothesis that Neanderthal had indeed been interbreed with modern man, and that we carried in us a trace of that lineage, even if it might be small. I maintained the position the there was an admixture, the obviousness lay right in front of our eyes if we only took a moment to see it.
I would also expect that beyond just the occipital bun, and other genes responsible for skull shape, that there was likely other inclusions that would have been very fortuitous to take from Neanderthal, on a purely physical level. These inclusion would be those that had helped Neanderthal adapt to the northern climate, including dietary/nutritional systems, pigmentation and hair types, and immune systems. Just for starters these inclusions would carry obvious benefits...and if one let their imagination loose on the idea of the admixture, the realm of the mind and brain comes to play.
She maintained, however, that no such admixture had taken place (nor could have taken place). As there is no trace of their mitochondrial dna in present man, making it impossible to have interbreed. I tried to explain the flaw in that logic to her, that mitochondrial dna is mother to child, and an admixture from Neanderthal male to human female would have produced a half-breed with human mitochondrial dna....but she maintained it wouldn't have been possible.
It irks me when mostly rational people fail to understand things that seem so obvious to me. But, I digress...
I have an occipital bun, it is rather pronounced, hats don't fit me properly, my head has a somewhat narrow, elongated appearance. I've been self conscious about it before, but it really doesn't seem to be viewed as unattractive or terribly disfiguring or anything, so I mostly just ignore it anymore....and don't wear hats.
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I am Ignostic.
Go ahead and define god, with universal acceptance of said definition.
I'll wait.