I have definitely run into the belief that humans aren’t evolving anymore (though not among scientists). I think people with an incomplete understanding of evolution look around, see most human beings survive to adulthood, and assume that there must be no more evolutionary pressures on us (perhaps with the phrase “survival of the fittest” tinging around inside their head). I honestly don’t blame anyone who hasn’t been exposed to the concept of e.g. sexual selection for making the assumption.

▲ delichon an hour ago | parent | next [-]

  There's been no biological change in humans in 40,000 or 50,000 years. Everything we call culture and civilization we’ve built with the same body and brain. -- Stephen Jay Gould, "The Spice of Life", 2000

Gould was an evolutionary biologist and Harvard professor, and one of the most prominent popularizers of evolution since Darwin, but somehow believed that it doesn't apply to modern humans.

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an hour ago | parent | next [-]

[deleted]

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remarkEon an hour ago | parent | prev [-]

That's such an extreme claim. It defies common sense. You'd have to proclaim that there was some event that _stopped_ evolution in humans, universally. How is that even possible? Especially 50k years ago. I'd be a little more forgiving if the claim was that evolution stopped in, say, 1999.

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RajT88 an hour ago | parent | next [-]

Rather a lot more things about human genomic history are known today compared to 2000.

Discoveries about being able to process lactose and when those genes evolved all were after 2000, for example.

Does it excuse Gould for making such bold claims? You have to decide I guess. That is a lot fuzzier.

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remarkEon 29 minutes ago | parent [-]

I guess I would need to read more of what Gould wrote. For example, did he claim that evolution in other species also stopped?

	▲	margalabargala a minute ago \| parent [-]
		I think the claim that humans stopped evolving is an uncharitable reading. Another would be, 50k years is such a narrow window that evolution cannot be observed across it.

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retrac 19 minutes ago | parent | prev [-]

Emphasis should be placed on "everything we call culture and civilization". There is a thought experiment that might help. Imagine we had a time machine, and no scruples, and we could go back and pluck babies from the past to experimentally raise them in modern American families. I'm pretty sure Gould would have argued that babies from 40k years ago would grow up to be behaviourally indistinguishable from modern humans.

	▲	remarkEon 6 minutes ago \| parent [-]
		Well, evaluating the nature of this thought experiment reveals what you actually believe about human evolution and development. I find it extremely hard to believe that someone from 40k years ago would be indistinguishable from humans today. Believing this requires you to imagine that there are no genetic selection pressures for things like intelligence, behavior, physical ability ... 40k years ago had Earth as an almost entirely different planet. Europe was frozen for most of the year, for example. There were no trees. Very, very hard to believe that people born back then could grow up to sit in front of a laptop today.

▲ knowaveragejoe an hour ago | parent | prev [-]

For the average person considering this question it also goes without saying that it's hard to grasp the time scales involved.