Pages

Tuesday, May 1, 2012

Humans still subject to natural and sensual selection (again)

The above headline is nothing new, but something still important to remind people about. (also we say 'sensual' instead of 'sexual selection' to keep this a family place. Crap, I just said 'sexual.') A little over a year ago a popular physicist got in some trouble for saying that humans were impervious to evolution because natural selection was no longer able to act on us smart creatures. Right after the scientist put a big smelly foot in his mouth I explained why this statement was incorrect (at best), and why you should learn biology from biologists rather than theoretical physicists.

I was reminded of this when I came across a study by Alexandre Courtiol and colleagues, out in PNAS yesterday, that examined whether natural and sexual selection were acting on an 18th-19th century Finnish population, based on local church records of births, marriages, etc. Natural selection refers to the differential survival and reproduction of individuals in a population, a disparity that generally arises because individuals may be better- or worse-adapted to their circumstances than others. Sexual (aka sensual) selection is a special type of natural selection, referring to how well individuals are able to acquire mates. Sure enough, Courtiol et al. found such differences between individuals in their Finnish sample. I have only gotten to glance at the paper, so I still need to check how they measured their variables (like fitness or mating success), but the last line of the abstract is what really stuck out at me:
Our results emphasize that the demographic, cultural, and technological changes of the last 10,000 y[ears] did not preclude the potential for natural and sexual selection in our species.
The fat lady in the opera of Human Evolution has yet to sing (this show's motto would be, "No fat chicks," if such a statement weren't sexist and offensive).

ResearchBlogging.orgRead for yourself!
Courtiol, A., Pettay, J., Jokela, M., Rotkirch, A., & Lummaa, V. (2012). Natural and sexual selection in a monogamous historical human population Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1118174109