From PhysOrg:
A team of researchers led by Gottfried Hohmann of the Max Planck Institute for Evolutionary Anthropology has discovered that the higher up a male bonobo is placed in the social hierarchy, the greater his mating success is with female bonobos. But even males who are not so highly placed are still in with a chance of impressing females.
Researchers reported for the first time direct support from mothers to their sons in agonistic conflicts over access to estrous females. Martin Surbeck from the Max Planck Institute for Evolutionary Anthropology discovered that the presence of mothers enhances the mating success of their sons and thereby causes mating to be more evenly distributed among the males. As bonobo males remain in their natal group and adult females have the leverage to intervene in male conflicts, maternal support extends into adulthood and potentially affects male reproductive success.
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