Evolved Again

Apparently it's big news that the human brain is still evolving. A couple of U.S. researchers announced recently that they'd isolated two genes connected with brain size that appeared to have evolved only over the past two dozen millennia. In other words, our brains changed in the past hundred generations. Why this would be surprising to anyone even glancingly familiar with evolutionary theory is beyond me. As long as we keep engaging in sexual reproduction, we're going to be evolving. The process ain't teleological, people.

Greg Wray, a Duke University evolutionary genomics professor involved with the study, told the Associated Press, "There's a sense that we as humans have kind of peaked." But, he added, "it's almost impossible for evolution not to happen."

Nevertheless, people both in and out of the scientific community were bemused by the study. I'm tempted to say that's because the intelligent design dorks are making so many headlines that any new information about evolution -- particularly that it's still happening in an observable fashion -- pricks up our ears. But I think what this study calls attention to is the kind of weird folk belief, alluded to by Wray, that somehow we've stopped evolving. Partly this is because the Darwinian tradition is focused on the past. This is what sets evolutionary theory apart from social and political theories of human change, which often examine how the species can change itself today in order to influence the future.

I bring up politics because I think they're ultimately to blame for our short-sighted view of evolution as a process that started 200 million years ago and ended roughly in the mid-19th century, when Darwin started freaking everybody out with his ideas about humans and apes. Few people are comfortable with the idea that they're just one step in a journey toward some other thing that will probably be much cooler and better than they are. That's why intelligent design has become so popular. It's an idea that makes evolution all about who we are right now, because somebody has been guiding everything to this exact point. In other words, we are totally perfect, and nothing will ever be better. Nice try.

Thankfully, the current version of homo sapiens is just that: a current version. We can take some pride in that. We're the very latest thing. We have features previous versions didn't have, like extra height and complicated symbolic systems for communicating. Even better, we now have a basic understanding of how we evolved. Plus, this version of homo sapiens can change itself with science faster than the previous versions could with sexual reproduction.

For example: We are about to have children born of three parents. Some medical researchers in the U.K. have announced they'll be experimenting with creating human embryos that have genetic material from two mothers and a father. The idea is to cure certain diseases inherited through maternal genetic material called mitochondrial DNA that exists outside the cell nucleus (where most DNA is housed). These babies will have one woman's nuclear DNA, another woman's mitochondrial DNA, and more nuclear DNA from the man.

How's that for changing the course of evolution? A human with three genetic parents is definitely a novel version of homo sapiens.

Of course, the people who believe that only some godlike creature or "nature" should be in charge of upgrading the species also think this is a naughty idea. Josephine Quintavalle, a rep for public interest group Comment on Reproductive Ethics, told the BBC, "It is undesirable to create children in this way. It will shock the world." Her response reminds me of the sort of thing an intelligent design adherent would say. Essentially she's arguing that we shouldn't continue to evolve, even though that's impossible.