Researchers at Stanford and the University of California-Santa Barbara claim that we may all live longer, thanks to the increased popularity of May-December relationships... and older men therefore fathering children with younger women. The study is really confusing, but here's how it's best broken down:

Evolutionary theory says that individuals should die of old age when their reproductive lives are complete, generally by age 55 in humans, according to demographer Cedric Puleston. But the fatherhood of a small number of older men is enough to postpone the date with death because natural selection fights life-shortening mutations until the species is finished reproducing.

I wonder if David Letterman will have another baby and help us all out even more... But no pressure, Dave, really. It's just the whole human race that's counting on you.