In a video clip that's made the rounds lately, Richard Feynman puts the essence of science in a nutshell: If your idea doesn’t agree with experiment or observation, it’s wrong. The sound bite was clipped from a much longer lecture, in which the famous physicist offered some important insights into the process of science.
And indeed, getting at the truth is complicated because it's not always obvious what agrees or disagrees with nature. If it were clear-cut, you’d never see two titans such as Richard Dawkins and E.O.Wilson in raging disagreement. But they are.
The Dawkins/Wilson war is over the roots of cooperative and altruistic behavior. I touched on the controversy more than a year ago in this column. There, I took on a question of more general interest: Do humans need to believe in God to be good? Both sides agree that we don’t. We’re social animals and we evolved to be cooperative and, to some extent, altruistic.
But how does natural selection do this? The existing paradigm rests on a concept known as kin selection or inclusive fitness, which is based on the idea that our selfish genes nudge us to help our relatives. The more related, the more we help. Dawkins and most of the biology community take this view, as did E.O. Wilson, until recently.
Wilson is famous for his groundbreaking work on social insects and his founding of the field of sociobiology (now evolutionary psychology). Now he’s abandoned kin selection and in its place embraced a concept called group selection – in which natural selection can favor some groups of organisms over others. In biology, the mention of group selection is not just controversial – it’s downright inflammatory.
Both Dawkins and E.O. Wilson are thoughtful, eloquent writers, but at least one of them must be wrong. Wilson lays out his case in his new book, “The Social Conquest of Earth,” which I’m in the process of reading. One of Wilson’s arguments is that kin selection uses rigorous math without a rigorous enough understanding one of the key variables – r – which quantifies degree of relatedness.
In this review, Dawkins is rather scathing:
The argument from authority, then, cuts both ways, so let me now set it aside and talk about evolution itself. At stake is the level at which Darwinian selection acts: “survival of the fittest” but, to quote Wilson’s fellow entomologist-turned-anthropologist RD Alexander, the fittest what? The fittest gene, individual, group, species, ecosystem? 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 multi-level selection: a bland, unfocussed ecumenicalism of the sort promoted by (the association may not delight Wilson) the late Stephen Jay Gould. Let a thousand flowers bloom and let Darwinian selection choose among all levels in the hierarchy of life. But it doesn’t stand up to serious scrutiny. Darwinian selection is a very particular process, which demands rigorous understanding.
The essential point to grasp is that the gene doesn’t belong in the hierarchy I listed. It is on its own as a “replicator,” with its own unique status as a unit of Darwinian selection. Genes, but no other units in life’s hierarchy, make exact copies of themselves in a pool of such copies. It therefore makes a long-term difference which genes are good at surviving and which ones bad. You cannot say the same of individual organisms (they die after passing on their genes and never make copies of themselves). Nor does it apply to groups or species or ecosystems. None make copies of themselves. None are replicators. Genes have that unique status.
There ought to be some kind of agreed-upon test that would settle this dispute. I haven’t yet read anything from either side giving us a specific observation or experiment to show that the other side is unequivocably wrong. Both sides claim their ideas describe nature to some extent. The fight is over which describes nature better.