"Nature versus nurture. The pendulum swings back and forth, and right now we're in the midst of a major lurch towards preoccupation with 'nature,'" said Professor Jon Seger at the April meeting of Humanists of Utah. There are current books by well-respected geneticists espousing an "enthusiasm for this modern form of predestinationism."

Professor Seger identified four "myths" about human genetic variation and spent the bulk of his presentation debunking them:

1. There are substantial genetic differences among the human "races."
2. Within populations, physical and mental differences are also largely genetic and heritable.
3. People could, in principle, be improved by selective breeding.
4. Civilization has relaxed natural selection to the point where less fit individuals reproduce as much (or more than) more fit individuals so that bad genes are increasing in frequency.

The first argument against these common conceptions was general in nature: the propositions could, in principle, be true. "The problem is that these beliefs lend themselves to odious applications involving nonfactual value judgments and rationalizations of events in which we could intervene. It is just good luck that these myths are untrue, or at least not true in the forms commonly believed. Thus a correct understanding of the facts can undermine certain kinds of social and political arguments by depriving them of key factual premises."

Professor Seger presented a variety of charts and statistics to undermine each of the four statements. Among the items discussed were genetic distribution schemes for common markers found on blood cells. The distribution of "blood types" is an effective argument that the whole notion of "race" among humans is fallacious. (myth one) Other studies showed that the vast majority of variation in human genetic makeup is found in small, isolated populations. For example, if an alien, wanting to capture breeding stock for an extraterrestrial human zoo, landed at a basketball game in Nephi and abducted the basketball players and cheerleaders, it would take with it some 80% of human genetic variation! (myth two) In fact humans are more genetically homogeneous than our nearest relative the chimpanzee (which goes to show you that if you have seen one chimp, you haven't seen them all!) (myth three) Finally, "bad genes" found in isolated populations often serve to provide a level of protection against some environmental threat. The classic example is that of hemoglobin variations among Africans and Mediterranean peoples that provide a natural resistance to malaria. (myth four)

After the lecture I overheard a small group exclaiming that at last they had "proof" of humanism. While I agree, I think it prudent to quote Professor Seger's disclaimer: "My comments on these myths will necessarily be very brief and in many respects very superficial and inadequate...I'm not the leading expert on any of these issues; I'm here because you invited me, and I decided to take on this issue because I think it is important, and timely, and close to the central concerns of your organization. I'll be quite happy if I succeed in raising your awareness of the issues and motivating you to learn more, and think more about them." He should still be happy!

--Wayne Wilson