Boy Moms More Social in Chimpanzees
According to a study by Proceedings of the National Academy of Sciences, mothers of sons are about 25 percent more outgoing than mothers of daughters among chimpanzees.
Boy moms spend about two hours more per day with their children. Researchers can´t explain the behavior and say it´s unclear if it is a "conscious" decision by the mothers.
One theory is that adult chimps are more attracted to male infants.