In an examination of why men and women age differently, Evolution is given way too much power.  It’s the problem with any totalizing theory: EVERYTHING can be explained.  Well, not really.   How is this falsifiable?  Is this the case in every society?  Might it be cultural that men act a certain way and then, in societies where men don’t act that way, they live the same length?  Aaargh.

But a more subtle effect may also be at work. Most students of ageing agree that an animal’s maximum lifespan is set by how long it can reasonably expect to escape predation, disease, accident and damaging aggression by others of its kind. If it will be killed quickly anyway, there is not much reason for evolution to divert scarce resources into keeping the machine in tip-top condition. Those resources should, instead, be devoted to reproduction. And the more threatening the outside world is, the shorter the maximum lifespan should be.

There is no reason why that logic should not work between the sexes as well as between species. And this is what Dr Clutton-Brock and Dr Isvaran seem to have found. The test is to identify a species that has made its environment so safe that most of its members die of old age, and see if the difference continues to exist. Fortunately, there is such a species: man.

Dr Clutton-Brock reckons that the sex difference in both human rates of ageing and in the usual age of death is an indicator that polygyny was the rule in humanity’s evolutionary past—as it still is, in some places. That may not please some feminists, but it could be the price women have paid for outliving their menfolk.