BERLIN - It is a scientific theory of longevity that has the whiff of homemade pie: people live longer thanks to the grandmothers who help raise them.Though first put forth more than a half-century ago, the “grandmother hypothesis” has gotten renewed attention with a recent study published in the Proceedings of the Royal Society B: Biological Sciences by University of Utah anthropologist anthropologist Kristen Hawkes.While other mammals like chimpanzees chase females who are no longer fertile from their midst, Hawkes notes that human women are among the very few mammals who live for decades after menopause.Read more at Worldcrunch.