The Foresight report into our obese future - predicting that at least half the population could be seriously overweight by 2050 - doesn't hesitate to deploy powerful metaphors in order to warn us. The shock tactic is explicitly being adopted by government as the best way to avert a social and economic calamity. Thus, scientists can be heard on the radio talking of nothing less than Armageddon.
What is also being stressed is that obesity is not the fault of the individual. Rather, our biology can be blamed. When we were hunter-gatherers, the story goes, we compulsively ate because we did not know where the next meal was coming from. Now we eat as if we do not know where the next meal is coming from, though of course we do. "If we just behave normally we will become obese," Sir David King, the government's chief scientific adviser has said.
It would be a tragedy if, for possibly the first time in history, future generations died at a younger age than their parents. However, implicit in the analysis is a theory of natural selection that, first, might be wrong; second, might lead to the wrong reason we face this problem today; and third, might leave obese people feeling that there is little they can do about their weight anyway.
The hunter-gatherer story is what the biologist Stephen Gould used to call a shaggy dog story. His point was that Darwinism has led to all sorts of human characteristics supposedly being "explained" by saying that they are the result of evolutionary adaptation when, in fact, evolutionary theory is simply not up to that level of explanation at all.
The philosopher Jerry Fodor explains why in the current London Review of Books. In short, there is increasingly good reason to think that all sorts of human characteristics, and those of other organisms, are not the result of evolutionary adaptation. They may be random. They may be the result of other natural mechanisms, evolutionary or otherwise.
Experiments that bred silver foxes for tameness provide a case in point. It turns out that as the creatures became tamer, they also tended to have floppier ears, greyer hairs and curlier tails. These characteristics have nothing to do with being tame, though the foxes do look cute. Neither were the breeders selecting for them. So, there is no teleological explanation to hand. Curly tails do not make silver foxes tame. It seems that it is just that tamer foxes arbitrarily have them.
This throws a spanner in the works for the now very common recourse to evolutionary psychology to "explain" things - the sort that claim why we have such and such a feature on account of what it gains for us, or gained for our hunter-gatherer ancestors. One of the more bizarre recent examples was the "explanation" that girls like pink, and boys blue, because women on the savannah had to search for red berries, and men could hunt better under clearer skies. Fodor concludes that biologists might tell these evolutionary tales for no other good reason than that it adds prestige to their research.
Similarly, perhaps, with the "reason" that we are becoming obese. It may well not be because a hunter-gatherer adaptive advantage of yesteryear has backfired on us today. That piece of science may be as much wishful thinking as the "explanation" offered by intelligent design. Moreover, it is easy to pose counter-examples. For example, presumably the supreme advantage that evolution would have conferred on our ancestors, and therefore left to us, is a profound enjoyment of hunting. So how come so many people loathe the very thought of it today?
This not only matters to science. It matters because, secondly, in relation to the rise in obesity, it could be that the diagnosis for why people are becoming fatter is entirely wrong. It might not be the fault of our past evolution and present environment. The dominant reasons for rising obesity might be, say, because people eat when they feel depressed as many increasingly do; or because of growing personal ill-discipline, if there is; or simply because people don't care. Building more cycle-paths would do nothing to ease that and, thus, nothing to stem the epidemic - and to be fair to the Foresight report it suggests other things that need to be done, beneath the headlines.
Third, the evolutionary accounts of phenomena like obesity are wrapped in an ideology of determinism. "It is in your genes" implies that there is nothing you can do about it; if you are fighting Mother Nature, then why bother? Hence the aura of fatalism that surrounds today's report, and the reaching after metaphors like Armageddon. But as Paul Gately reported, people can lose weight, though it might be hard and the problem is complex. Surely, though, people need to be empowered to tackle it, not led to believe that they are hapless creatures of their genes.
