ends of thick, dry branch by hand and use foot to push forcibly against it, in order to break it in two. Also reported from Goualougo. 7. See video. break open by pushing chin Hold large fruit with fairly soft shell such as ripe Saba comorensis or lemon in mouth and push chin with hand or wrist in order to break open and eat contents. break tree Break tree trunk by leaping and pushing against it, or pushing and pulling with hand repeatedly. Kortlandts Break tree. Element of charging display by adult male. leap, push, pull. Also when eating pith from small tree. Also in bonobos. See video. break wind See fart. bristle Goodall Hair erection: The hairs stand on end. Plooijs Hair erection or pilo erection. Bonobos