We are still evolving (and how!)

Recent common sense in general science and among biologists has been that humans are no longer evolving. Natural selection is a process which depends on differential rates of death, and we've gotten so good at avoiding death (at least before reproductive age) that lots of people with theoretically disabling genes still get to pass those genes on (I, for example, have horribly flat feet and a genetic disposal to tear my ACLs. While not great for my athletic career, this probably will not, fingers crossed, affect my ability to reproduce).

Some recent work in the field of genetics, however, is possibly turning this assumption on its head. Mostly through projects like the HGP (Human Genome Project), and advanced techniques for processing very large amounts of data, we can now compare and trace lots of different genes in the genomes of lots of different people. When examined on this level, there is some preliminary evidence that our genome is actually going under extremely fast selection, in geo-historical terms. It could be that 10% of our genes are actually under some kind of active selection, which is very much on the high end for evolution. Most of this work is pure statistics, and based on the assumption that if mutations are inherently random, and we see a whole bunch of alleles (specific versions of genes) changing in the same direction over some appreciable amount of time, then this is indicative of active selection for these specific alleles. With a few notable exceptions (like some work on selection for the gene that allows adult humans to digest lactose), these genetic changes cannot be linked to specific functions, and so we don't know exactly what kind of gene is being selected for. But, from a certain perspective, it makes lots of sense that we are actually under greatly accelerated natural selection, since the rate of changes in our lifestyles, as well as the increased rates of disease evolution that are likely from increasing population densities, are in the big scheme of things, very recent phenomena. Either way, very interesting to think that for all of our medicine and modern mumbo-jumbo, our genes are still being aggressively selected.