Hey, kid! Check out the SF Zoo's newest little one, a Francois' langur who was born there on Sunday, February 12.

Also known as François's leaf monkey, Tonkin leaf monkey, white side-burned black langur, these tree-dwelling monkeys have an interesting social structure, according to Wildscreen ARKive:

The group consists of 4 to 27 (usually around a dozen) individuals and led by the females, who operate a reasonably changeable hierarchy amongst themselves, particularly when it comes to caring for the young. There is usually just one adult male in the group who will not participate in caring for the young, except to respond to their distress calls. He will also rarely groom other members of the group, but expects to be groomed himself.

Females share responsibility for the infants, who are born singly once a year. They are immediately cared for by ‘allomothers’ as well as their own mother, who will nurse the young monkey for up to two years before weaning. Once weaned, the bond between mother and infant is no different than between any other members of the group. After three or four years juveniles become sexually mature, and will commonly leave to join another group or to form an all-male bachelor group.

With a population diminished by wartime bombing in their native habitat of Vietnam, reductions in forest size and being "extensively hunted for food and for use in traditional 'medicinal' preparations," Francois' langurs are considered "endangered." The SF Zoo's group "originally came to San Francisco as a gift from the People’s Republic of China," they say, and can be seen at their Thelma and Henry Doelger Primate Discovery Center.