https://purescience.news/article?id=959625

Good parents and faithful partners live longer lives
Our evolutionary ancestors prioritising sex over survival could be why men don’t live as long as women, according to a new study. Across the world and throughout history, men have generally lived shorter lives than women. To find out why humans evolved this way, a group of researchers at the Max Planck Institute for Evolutionary Anthropology, in Germany, didn’t look at human history – but instead searched for clues from our animal cousins. Their study, published in Science Advances, examined over 1,000 animal species to track down which evolutionary traits were common amongst species where one sex tends to outlast another. They discovered that, though genetics does seem to play a part, monogamy was also a key factor in male longevity. Meanwhile, child-rearing might have helped females expand their lifespan. In humans, women live an average of 5.4 years longer than men, but we’re not the only species where one sex outlives another. In fact, in 72 per cent of mammals, females outlast their male counterparts by an average of 12 per cent. The female lifespans of one species, the moose, can be over twice as long as males’. But this isn’t true across the animal kingdom. In birds, it’s the males that tend to live longer – by an average of 5 per cent in the majority (68 per cent) of species. One of the leading explanations is our chromosomes, given it’s one of the most fundamental differences between sexes. In mammals, females have two X chromosomes, while males have a shortened Y chromosome. Study lead Dr Johanna Staerk told BBC Science Focus explained that because males have only one copy of the X chromosome, “any harmful mutations on that chromosome are more likely to have an impact, since there isn’t a second copy to compensate.





