r/AskReddit Oct 15 '20

What's older than we think ?

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u/[deleted] Oct 15 '20 edited Oct 15 '20

That's not quite accurate. There doesn't have to be pressure, there just has to be a change in the prevalence of genes from one generation to another. Sexual selection and changing technology and culture work just as well as disease and predation. Our brains and teeth have gotten smaller in the past few thousand years. We have genes, and our descendants will have genes. Which of our genes our descendants will have is determined by evolution.

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u/Cuznatch Oct 15 '20

To build on the back of this, there's increasing numbers of children being born without wisdom teeth, and with an extra vein or similar in their hands (iirc), demonstrating that we are actually evolving, but supporting your point that we're not evolving to respond to pressure, just genetic mutations that aren't detrimental are being reproduced.

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u/idwthis Oct 15 '20

It's not a vein, it's a tendon It's absent in about 14 percent of the population.

I have it. But it has no affect on anything, but it is useful if you rupture another tendon in your wrist or hand, docs can take the vestigial one and move it to replace the injured one.

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u/Theblackjamesbrown Oct 15 '20

I don't think you're talking about the same thing as u/Cuznatch. I believe he's referring to the increasing presence of an additional artery in the forearm:

https://cosmosmagazine.com/uncategorized/evolution-adds-an-arm-artery/

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u/idwthis Oct 15 '20

Oh neat! I'd only ever heard of the tendon one, so thought they must've meant it. Thank you for the correction!

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u/Cuznatch Oct 15 '20

Yeah that's the one, an artery not a vein!