They're normally, male chimpanzees, not particularly interested in infants, but when they are campaigning like that, they get very interested in infants and they tickle them, and they try to curry favor with the females.
Geralmente, os chimpanzés machos não se interessam por filhotes, mas, quando estão em campanha, ficam muito interessados e brincam com eles e tentam bajular as fêmeas.