Mairi Macleod in New Scientist:
FROM feckless fathers and teenaged mothers to so-called feral kids, the media seems to take a voyeuristic pleasure in documenting the lives of the “underclass”. Whether they are inclined to condemn or sympathise, commentators regularly ask how society got to be this way. There is seldom agreement, but one explanation you are unlikely to hear is that this kind of “delinquent” behaviour is a sensible response to the circumstances of a life constrained by poverty. Yet that is exactly what some evolutionary biologists are now proposing.
There is no reason to view the poor as stupid or in any way different from anyone else, says Daniel Nettle of the University of Newcastle in the UK. All of us are simply human beings, making the best of the hand life has dealt us. If we understand this, it won't just change the way we view the lives of the poorest in society, it will also show how misguided many current efforts to tackle society's problems are – and it will suggest better solutions.
Evolutionary theory predicts that if you are a mammal growing up in a harsh, unpredictable environment where you are susceptible to disease and might die young, then you should follow a “fast” reproductive strategy – grow up quickly, and have offspring early and close together so you can ensure leaving some viable progeny before you become ill or die. For a range of animal species there is evidence that this does happen. Now research suggests that humans are no exception.
Certainly the theory holds up in comparisons between people in rich and poor countries. Bobbi Low and her colleagues at the University of Michigan at Ann Arbor compared information from nations across the world to see if the age at which women have children changes according to their life expectancy (Cross-Cultural Research, vol 42, p 201). “We found that the human data fit the general mammalian pattern,” says Low. “The shorter life expectancy was, the earlier women had their first child.”
But can the same biological principles explain the difference in behaviour between rich and poor within a developed, post-industrialised country?