If one theme emerged in the past year's scientific research, it's that no two humans are alike--at least, not when it comes to their genes. Myriad of discoveries in 2007 found a wide variation between one person's genome and another's. How did we get to be so different? One of the newest genetic variation studies shows that human evolution might have sped up over the past 10,000 years. "We found that human evolution was going really fast and it couldn't have been going that fast for very long," says anthropologist Henry Harpending at the University of Utah, who coauthored a study that appeared in the Proceedings of the National Academy of Sciences. Harpending and his colleagues found that right after the ice age, as humans began living in more diverse environments, their genomes adapted to their various habitats.
The research raises important questions. How do we understand human equality in the face of biological inequality? "I think we're going to have a major revision in our shared attitudes about what social decency and justice are," says Harpending. He spoke with NEWSWEEK's Sarah Kliff about his research and the social implications of biological differences. Excerpts:
NEWSWEEK: How did you get started with this research?
Henry Harpending: Darwin said that to get rapid evolution you need a big population. It occurred to us that there was a massive increase in human numbers, especially since farming. So we looked into this issue of acceleration and found both evidence and theory that say that yes we ought to have accelerated and indeed we have.
In order to get this rapid burst of evolution we need two things in any species. We need big numbers, in order to have a supply of mutations, and we need an environmental change. We happen to be in the midst of both. A species like cockroaches, for example, have big numbers but they haven't changed their environment, so they are probably close to equilibrium. Once you put humans in new environments, then there are all sorts of ways to evolve.
So how does that change humans?
In different populations, from Northern Europe to China to Japan, there are different [genes] that are becoming more common in different populations.
There is some concern that research like this, which reveals biological inequalities, could engender racism. What do you think about that?
If you think that justice and equality demand biological identity, I think it could. I think that human rights and civil rights don't depend on the assumption that where our ancestors were 500 years ago were equivalent [to one another]. Having said that, we do, especially in America, have the idea that all groups have to be equivalent. I think that idea is not too long in this world.
Humans are different, they are diverse and a lot of that diversity seems to be in the genome. If I can't sing, it's not because my music teacher repressed me, it's because I'm different. In our public life we have to open ourselves to the idea of biological diversity.
Why do you think the idea of biological differences is so alarming?
Beats me. I think it's bizarre [that it's alarming]. I know part of it is that a big phenomenon in academics in the 20th century was the rise of social science. Social science, for its validity, needed to get rid of biology. There was the notion that arose by proclamation that biology was irrelevant to social behavior, that everything was learned.
Do you think your research is risky?
The kind of thing I do is very much mathematics, which means that I don't have to live off of federal grants. I can speak freely. If I were living on grants, I'd be terrified because it is controversial. Certainly our government could decide that they didn't want to spend money things that are politically dangerous. There certainly is that.
It seems like the research community has accepted the idea of genetic diversity. Do you think society will?
I think we can't avoid it. I think we're going to have a major revision in our shared attitudes about what social decency and justice are. I think we can't duck it any longer.
So, if society does accept genetic diversity, how will that play out?
We've gone far enough that I don't think bigotry will ever be acceptable again. I think we'll have to learn to treat people as individuals. The differences within groups are much bigger than the differences between groups. You've got to tell the truth, and I guess I have faith that underlying all of [this research] is a lot of decency, goodwill and optimism in the citizenry, and I think we'll handle it decently.