Not even the “Grandma looks after the kids” pop sci filler buys this one. From Steve Fleischfresser at Cosmos:
Jacob Moorad and Craig Walling from the Institute of Evolutionary Biology at the University of Edinburgh in the UK drew on one of the world’s most extensive sources of genealogical information: the Utah Population Database (UPDB), housed at the University of Utah, and drawn from the family records of Mormon settlers to the state. The database contains information on more than eight million people.
Moorad and Walling, using a subset of the UPDB for the first empirical test of the models, sought to discover if there is positive genetic correlation between “late-age lifespan and fitness” which is assumed in all three models. Such evidence would be, the authors write in the journal Nature Ecology & Evolution, “‘the smoking gun’ necessary to demonstrate the true efficacy of an evolutionary pathway to maintain post-reproductive survival.”
In fact, they found no indications at all of that supported the contentions of any of the three leading theories. The evolutionary reason why old women exist remains unknown. More.
The article is unusual in that it makes clear that the conventional pop Darwin explanations don’t work without proposing another one. The most we hear is that one or other of the gimcrack models might have been “disrupted over time.”
But it’s not clear, on reflection, that an evolutionary explanation for human female longevity is even needed.
One difference between old women and old cows is that women are aware of death and can think of means of avoiding it. Such means might include establishing moral and legal rules against killing one’s parents and inheritance systems that give power to seniors over juniors. And making kindness toward the aged seem as virtuous as kindness to children. These systems have been around for a long time.
Consciousness, however it came to exist, drives them, not evolutionary fitness. The grandmother-established systems could be less evolutionarily fit but nonetheless more likely to prevail.
See also: Evolutionary medicine: Insomnia in the elderly is due to evolution?
The Grandmother Hypothesis, yet again
and
Menopause caused by guys staying home