October 20, 2009

Human Evolution In Action

Humans are not immune to evolutionary pressures and that makes some folks wonder what future humans will look like as we continue to evolve.  These folks think that we'll be shorter, heavier, have better hearts, and women will be fertile for longer in their lives.  Not dramatically so but probably enough to notice.  Not sure why they're focusing on women -- seems as though those traits would affect men as well except, obviously, for menopause. 

But that's not the only school of thought on the issue.  There is a somewhat depressing theory posited that humanity will split into two sub-species with one having clear dominance over the other, not unlike the terrifying vision of the future in H.G. Wells' Time MachineTranshumanists believe that we can and should artificially interfere with our descendents' attributes.  Still others suggest that human evolution is done; the theory goes that by taking control of our environment, selecting mates for reasons unrelated to survival, creating tools and medicine to accomodate for physical deficiencies, and so on, we have removed the pressure of natural selection and instead will continue indefinitely like we are now, for so long as we have technological mastery of our world.

I'm actually closer to the "evolution has stopped" school of thought for humans -- because we have lessened the impact of things like susceptibility to diseases through vaccinations, improved nutrition generally, and created contraceptive devices to disconnect sexual behavior from reproduction.  But I wouldn't necessarily think that we've stopped evolving.  Rather, I'd say that we're introducing a new set of criteria for reproduction.  And what those are, I'll say, are not yet clear enough after only a handful of generations of serious technological and medical relief from the pressure of natural selection.  Let's concentrate on finding a way to sustain our industrialized existence first, and let human evolution take care of itself for a while.

1 comment:

zzi said...

"Hewitt responds that he is a lawyer, and Dawkins makes a big show of complaining about that."

His voice portrayed his annoyance after that exchange. Towards the end they seem to soften a bit.