Teen motherhood: Evolutionary strategy.

There’s a whole shovel-load of politics wrapped up in this New Scientist report on the evolutionary effects of poverty on human reproduction:

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.

It is not simply a case of teenage girls from deprived backgrounds accidentally becoming pregnant. Evidence from many sources suggests that teen pregnancy rates are similar in poor and affluent communities. However, motherhood is a choice, as both Geronimus and Johns are keen to point out. Teenage girls from affluent backgrounds are more likely to have abortions than their less-privileged peers. In terms of reproduction, the more affluent girls are best off concentrating on their own career and development so that they can invest more in the children they have at a later stage. “It seems that girls are assessing their life chances on a number of fronts and making conscious decisions about reproduction,” says Johns.

Still, reducing poverty alone probably isn’t the answer. In their book The Spirit Level (Allen Lane, 2009), epidemiologists Richard Wilkinson and Kate Pickett, of the universities of Nottingham and York, UK, respectively, emphasise the degree of income inequality in a society rather than poverty per se as being a major factor in issues such as death and disease rates, teenage motherhood and levels of violence. They show that nations such as the US and UK, which have the greatest inequality in income levels of all developed nations, also have the lowest life expectancy among those nations, the highest levels of teenage motherhood (see diagrams) and a range of social problems.

Observation 1: These studies are just dying to be misquoted.

Observation 2: We are never as smart or self-determined as we want to be. Our environments constrain us. In other words, these things matter.