Report in Current Biology : It is more common in females than in males . Young often carried sticks in a manner similar to mothers do for their young . The chimps typically carried sticks as weapons , but sometimes exhibited doll - play behavior . Research paper was based on more than a decade of chimps in Uganda .
Report in Current Biology : Behavior is more common in females than in males . Young chimps carried sticks in a manner similar to mothers caring for their young . Boy chimps typically used sticks as weapons , but sometimes showed doll-play behavior . Research paper was based on more than a decade observing chimps in Uganda .