If your idea of a hot hookup is tiptoeing down a basement staircase while the guy you just went for drinks with tells you in an urgent, husky whisper, "Shh, my mom's asleep," you're probably a muriqui, a New World species of matriarchal monkeys where mother-son proximity is the biggest turn on there is.
A new, icky study that looked at the genetic data in 67 muriqui fecal samples suggests that the Brazilian monkeys demonstrate a strong mother-son bond — so strong, in fact, that the presence of mother muriquis may help their sons find a mate. Researchers say that the "egalitarian and peaceful" muriquis don't exhibit some of the more competitive, violent traits evident in male-dominated species because female hegemony ensures that all males have the same access to reproduction. With no need for males to fight for mating dominance, muriquis have avoided the infighting seen in other primate, ahem, societies. Among some of the previous suppositions about muriqui society that this new study confirms is that forging a lifetime bond with his mother increases a male muriqui's reproductive success.
Unlike meddlesome bonobo yentas, muriquis do not interfere with their sons' sexual overtures — they just watch, which, however voyeuristic and weird it may seem to us, has tons of social benefits for the muriquis, including female longevity and more diverse reproduction. "What we see is that no one male is controlling reproduction," notes UW researcher Karen Strier. "The pattern is that a lot of different males are siring infants, confirming what we had predicted from their behavior." No word yet on whether scientists have observed the same social benefits from Italian men hanging around their mothers' houses, scarfing down free meatballs and leaving dirty laundry all over the floor, but Italy's really nice so there must be something to it.
If you're like me and avoided seeing Rise of the Planet of the Apes this summer because you also fear that a violent ape uprising (they have hands) is right around the corner, the muriquis offer a ray of hope for a more peaceable post-human primate society. However, it's not all sunshine and unabashed humping in the Brazilian Atlantic Forest where the muriquis live — at a population hovering around 1,000, the muriquis are a critically-endangered species, which I'm sure some men's rights douche is going to mention as some kind of proof that the muriqui matriarchy isn't as wonderful as it seems.
Image courtesy of Carla B. Possamai/Universidade Federal de Espirito Santo, via the University of Wisconsin-Madison.