selection on different levels (Score 1)

I just wanted to point out that selection can take place on many levels, for example, there is selection at the gametic level (sperm and eggs), and at the embryonic level.

I can't quote a number but I once heard that a high percentage of early term pregencies are miscarried. Selection could be acting at this level to select, for example, embryos that are resistant to certain outside toxic substances which disrupt development. In the long run these fetuses would come to term more often thus the alleles that were selected would increase in frequency in the population. These alleles might also have other affects on adult's ability to resist these substances later in life.

I don't think evolution in humans will ever end--we might go extinct--but evolution might be acting in ways which people have not considered. Remember that evolution by natural selection is defined as the change in frequency of an allele in a population.