al@gtx.com (Alan Filipski) (01/23/91)
In article <72753@bu.edu.bu.edu> colby@bu-bio.UUCP (Chris Colby) writes: > We, as in humans, are not evolving. Given that just about >about everyone lives to reproductive age and reproduces, natural >selection is not acting on our species. Also, the population size >of human beings is such that genetic drift does not take place. > To be a little more accurate, >some small amount of selection and drift is most likely occuring, >but it is negligible compared to other living species and our exposure I don't have the figures, but I'm sure that the average South American reproduces at a much higher rate than the average European. If you consider the (currently) low birthrates of Europeans, Euro-Americans, and Northern Asians and the high birth rates of American Blacks, South and Central Americans, Philipinos, Pakistanis, etc, I'd say that "we" are getting darker-skinned at a good clip, with all the genes associated with darker-skinned populations increasing in frequency. On the average, darker skinned people (and catholics) thus have greater fitness than WASPS. It's a strange kind of fitness, though, since it is only statistically rather than causally related to genotype. There is nothing, I think, intrinsic that causes a Mexican to have more kids than a Frenchman-- it's just where they happen to be born. Would it be technically considered group selection? I don't have a broad enough knowledge of biology to say whether such frequency change is negligible compared to gene frequency changes in other species. Perhaps so, but only because we live in extraordinary times of very rapid artificial environmental change (A "major extinction event", I forget who has said). Also, I believe that almost any kind of speculation about human selection starts many otherwise objective people frothing at the mouth for political reasons. Maybe this is one of those subjects. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ( Alan Filipski, GTX Corp, 8836 N. 23rd Avenue, Phoenix, Arizona 85021, USA ) ( {decvax,hplabs,uunet!amdahl,nsc}!sun!sunburn!gtx!al (602)870-1696 ) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
north@manta.NOSC.MIL (Mark H. North) (01/25/91)
In article <1435@gtx.com> al@gtx.UUCP (Alan Filipski) writes: > >Also, I believe that almost any kind of speculation about human >selection starts many otherwise objective people frothing at the mouth >for political reasons. Maybe this is one of those subjects. > Yes, you better check your little red book on politically correct ideas before you float another one like this. 8^) Mark