Thursday, 28 August 2008

Is it true about men ?

This piece of news may not go down well in a largely monogamous nation like India, but new research suggests that men who marry more than once tend to outlive their single-spouse counterparts, reports In defence, it cites findings from a study by Virpi Lummaa, an ecologist at the University of Sheffield, UK, that says men aged over 60 from 140 countries that practiced polygamy lived on an average 12 per cent longer than monogamous men.Lummaa's findings were presented last week at the International Society for Behavioural Ecology's annual meeting in New York.

However, the study is not meant to be a validation of polygamy as much as it set out to answer the question why men, and women, live so long. With women it has long been considered to be a result of the grandmother effect, which makes sense if one considers that unlike most mammals, women live long past menopause. Conventional wisdom has it that spoiling grandchildren, as we know it in India, is one of the contributory factors to female longevity. Every decade since menopause gives the woman two more grandchildren to dote on.

For the male of the species, however, it seems that longevity is not about emotion but physiology, since unlike the distaff side they can reproduce well into their 60s, 70s and, thanks to the little blue pill, even into their 80s now. But Lumma and colleague Andy Russell were not sure if this was it, or if there was a grandfather effect on them as well. After considering data from 18th and 19th century Finns (who did not practice contraception and among who the Church enforced strict monogamy) the researchers gave up the notion of grandfather effect on men. Next they compared the ages of men from polygamous nations to those from monogamous ones, spreading their study across 189 countries in all. Using WHO data they ranked the nations on a scale of 1 to 4, one being totally monogamous to four being totally polygamous. To even out the nutritional and other kinks between the developed and not-so developed world they factored in the nation's GDP, average income etc. Discounting female longevity as the reason for the male's long lifespan, the study said if that were the case then both monogamous and polygamous men would live for about the same length of time.

But, the study said, fathering more children with more wives seemed to be the reason behind male longevity. In short, those who remain sexually fertile into their old age tended to live longer. Researcher Lumma herself stresses that this is not a fool-proof study. Terming the 'monogamy score' as a crude stab, she said they are working on assessing marriage patterns which may blow this finding apart. Chris Wilson, evolutionary anthropologist at Cornell University, Ithaca, New York, however finds it a "valid hypothesis and good prediction". "It doesn't surprise me that men in those societies live longer than in monogamous societies where they become widowed and have nobody to care for them," he adds.

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