Male chimps prefer older mothers to young female chimps:
To a young male chimp there is nothing so attractive as wrinkles, sagging skin and bald patches in a female who is old enough to be his great-great-grandmother.
... and it makes perfect evolutionary sense. Here's why:
The toll that age and a life having babies can take of a female chimp is, to the virile male, merely a sign of success that promises his offspring a genetic head start in life.