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ok, first let me relate to you a saying by my Developmental Psychobiology Proffessor Mathew Sharps (look him up, several books on development of cognition and gestalt/feature intensive processing theory). "Evolution doesnt have to work WELL, it just has to work."
with that in mind, are we evolving? Of course we are. But we are changing the way in which we evolve. over the past couple of pages, we have seen ideas put forth that humans adapt our environments to our liking (which we do), and that intermingling of the "races" is evolution (which it is not... more on that in a sec).
First, "race" is socially defined, and is an inane distinction for two reasons: 1. if i am your typical American mutt (mostly European), statistically i have more genes in common with a native African than with any Englishman. (if u dont believe me, look it up. there was a fantastic documentary on PBS years ago that did just that experiment). 2. True evolution is not a change in any individual, it must be on a species level. change in an individual is mutation (or the influence of teratogens), and it is only once the relative gene frequency within a population increases that it can be called evolution. the biggest differences between ethnicities are pysical features, and these are the result of environmental factors, so putting a resistance to sunburn into a person that lives in the modern world of sunblock accomplishes nothing.
now, back to the first point: we have adapted our environment to our liking, with many interesting side-effects. there is a 600% increase over normal in rates of autism in the central valley in California because of polution and pesticide use. nationwide, there are increases in fetal alcohol syndrome, cancers of all kinds, obesity. the list goes on and on. Individuals with Down's syndrome used to barely make it to adolescence, and now live into their 70s fairly regularly. can any of these be seen as evolution? not really. relative gene frequency is still way down on most of these (obesity not even necessarily genetic in nature). what we are seeing is the selective pressures against teratogenic influence and pesticide use, but we are trying to adapt our environment to fit our needs. what we end up with is the survival of genes that should by all rights and means have been fatal. the implications for this are not known by anyone, but it will be our children and our children's children that will learn the cost of our dealings with nature.
Food for thought
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