Male mountain gorillas don’t seem to know or care which young are theirs. But nearly all males tolerate the company of kids. Unlike any other great ape that’s been studied in the wild, these males — bruisers twice the size of females, with huge muscles and teeth — are essentially babysitters. Some pick up the kids, play with them and even sleep cuddled together. This male company can protect very young gorillas against predators, and it keeps the young from being killed by intruding males. Another important benefit might be social, Rosenbaum speculates. The young gorillas mingling around an adult male might pick up social skills like human toddlers do from their peers at daycare. Additionally, research has shown that the relationships between young gorillas and adult males persist as those kids grow up. Another tantalizing hint about how male gorillas benefit the young in their group comes from a recent paper on young mountain gorillas whose mothers died. Losing their mothers didn’t make these orphans more likely to die themselves, the researchers found. Nor did they experience other costs, such as a longer wait before having their own young. The orphans’ relationships with others in their group, especially dominant males, seemed to protect them from ill effects.