Males who baby-sit children, not necessarily only their own, are likely to have greater reproductive success, claims a research on gorillas, that suggests an alternative route by which fathering behaviours might have evolved in humans.
"Mountain gorillas and humans are the only great apes in which males regularly develop strong social bonds with kids, so learning about what mountain gorillas do and why helps us understand how human males may have started down the path to our more involved form of fatherhood," said lead author Stacy Rosenbaum, post-doctoral student at the Northwestern University in the US.
According to Christopher Kuzawa, co-author and Professor at the university, the findings run counter to how we typically think of male mountain gorillas -- huge, competitive and with reproduction in the group dominated by a single alpha male.
"Males are spending a lot of time with groups of kids -- and those who groom and rest more with them end up having more reproductive opportunities," Kuzawa said.
"One likely interpretation is that females are choosing to mate with males based upon these interactions."
While traditionally it has been believed that male caretaking is reliant on a specific social structure, monogamy, because it helps ensure that males are taking care of their own kids.
The new study, published in the journal Scientific Reports, suggests that there is an alternative pathway by which evolution can generate this behaviour, even when males may not know who their offspring are, Rosenbaum said.
This raises the possibility that similar behaviours could have been important in the initial establishment of fathering behaviours in distant human ancestors.
"In human males, testosterone declines as men become fathers, and this is believed to help focus their attention on the needs of the newborn," Kuzawa said.
The study found that even after multiple controls for dominance ranks, age and the number of reproductive chances they get, males who have these bonds with kids are much more successful.