Scientists Ask Why Humans are Nice. I Ask: Are Humans Nice?

This is my column for next week. It will also appear in the Health and Science section of Monday's Philadelphia Inquirer:

It's nearly impossible to write objectively about the science of human kindness, cooperation, and altruism if you are, in fact, a human being. That's especially true now that there's a rift in the evolution community over two competing theories to explain why we're nice or, in technical terms, eusocial.

Since the best way to deal with bias is disclosure, I'll admit I've had more vicious hate mail than usual this week, and so when I hear the world eusocial, I think my part of the universe is mal-social. When the scientists talk about understanding why we're nice, I say, "where?"

Biologist David Sloan Wilson, who is enmeshed in the scientific dispute over the evolution of niceness, says it's understandable that our personal attitudes come into play. Those who value individualism may gravitate toward the theory of kin selection, which is favored by Richard Dawkins. Those who have a more communitarian attitude may be more open to an idea known as group selection, also called multilevel selection, which was recently championed by the equally prominent scientist-author E.O. Wilson.

Group selection, roughly, is the idea that Darwin's theory can act on groups as well as individuals, and that genetic tendencies toward cooperation can proliferate when groups of people cooperating outcompete groups that are constantly hitting one another over the head with clubs and hogging all the food. Kin selection, on the other hand, equates kindness with benefiting relatives and others who share genes.

The dispute has festered for years, but last week things came to a head. In April E.O. Wilson released his latest book, The Social Conquest of Earth, in which he argued that our social nature is the key to humanity's successful spread around the planet. He also makes the contentious claim that group, or multilevel, selection is the right way to explain our social roots, and kin selection is not.

Earlier this month the book got a scathing review from Dawkins, who is famous for his science popularization as well as his cutting wit: "Just as a child may enjoy addressing an envelope: Oxford, England, Europe, Earth, Solar System, Milky Way Galaxy, Local Group, Universe, so biologists with non-analytical minds warm to multilevel selection. …"

I asked Penn evolutionary psychologist Rob Kurzban to weigh in. He said we should all be careful not to see altruism where it doesn't exist or try to invoke complicated explanations for it when ordinary natural selection does the job.

First of all, human altruists usually prosper. People who help others gain allies, which benefits them, or they improve their reputations. People who act selfishly are punished with public shame — think of the captain who abandoned his sinking cruise ship off the Italian coast. Experiments show that people are much less altruistic when they think nobody is looking, Kurzban said. We should, in other words, be realistic about just how nice we really are.

Being nice himself, Kurzban pointed me to the ongoing discussion on the evolutionary psychology Facebook page, where attention had focused on a piece by David Sloan Wilson, a professor of biology at Binghamton University who is a known champion of group selection.

His piece, called "Richard Dawkins, Edward O. Wilson, and the Consensus of the Many," ran on his website, called "This View of Life." He wrote that both kin selection and multilevel selection can be useful for describing human behavior. "The many," in his opinion, refers to the bulk of the biology community. He claims the many take a middle ground and accept the usefulness of both theories, though at the end he adds the disclaimer that the many are invited to disagree.

So I called Sloan Wilson to get him to explain how two seemingly different ideas could be compatible. "It's like looking at a mountain from the east and the west," he said. Both views give you information.

I wanted him to explain how kin selection worked on non-kin and whether this has anything to do with the fact that we humans are more than 99 percent genetically identical to one another. Sloan Wilson said the relatedness used in kin-selection theory is based on how much more related two individuals are than two random individuals would be. Siblings are more closely related than cousins, for example.

And yet, he said, kin selection has been expanded into a theory called inclusive fitness, which can act on non-relatives. Imagine, he said, that we both shared a gene for being nice. Even if we're not related, we might help each other get food, or get out of trouble, because we share this gene. Our cooperation helps the niceness gene propagate itself. It all fits nicely with the selfish-gene concept popularized by Dawkins: Selfish genes can make us nice, and in doing so, they help themselves.

But what about the fact that many altruists are acting in their self-interest?

While ordinary natural selection may explain how such people survive now, it's harder to explain how altruistic groups arise in the first place, or how our ancestors evolved from more selfish animals to us, Sloan Wilson said. Now that we're surrounded by other altruists, being nice pays off.

Group selection, he emphasized, is not the idea that traits evolve for the good of the species. It's often confused with that, he said, but group selection can take place among much smaller groups. The important point is that it can influence the course of evolution if traits that are disadvantageous for individuals within groups can nevertheless propagate because they cluster in groups that outcompete other groups.

In the early 20th century, the idea of group selection was accepted uncritically, and then rejected with force in the 1960s, he said. The situation was reminiscent of the way Darwinian evolution killed off its predecessor, known as Lamarckian evolution. In reality, Darwin accepted some of the wrong concepts attributed to Lamarck. And Lamarck's evolution was a huge leap over the creationist dogma of his time. But ever since Darwin, "it's been portrayed as stupid."

Ideas rejected in this way are made taboo, Sloan Wilson said. "All [that] students learn about group selection is you never dare invoke that." Unless, that is, you are a double Pulitzer Prize-winning writer like E.O. Wilson.

As for Wilson's new book, "the stuff [from critics] about kin selection is a big distraction," Sloan Wilson said. He recommends that people concentrate on the more central point, which is about the consequences of human social behavior. "It accounts for our worldwide domination," he said, "which is not necessarily a good thing."

Despite a stormy week in which I briefly thought the only being I could trust was my cat, everyone who was interviewed for this story was very cooperative, even altruistic. So maybe humans are not so bad after all.

Contact Faye Flam at 215-854-4977, fflam@phillynews.com; @fayeflam on Twitter.