Forming this socially monogamous pair causes the males to feel linked to the offspring, and motivates the males not only to defend the offspring against infanticide from non familial primates but also to never commit infanticide against their own offspring.
Forming this socially monogamous pair causes the males to form parental relationships and social bonds with the female's offspring. These bonds motivate males to defend their offspring against infanticide from non familial primates and to never commit infanticide against their own offspring.