Assertion: ape's behavior | /r/HasProperty | de waal
Facets:
Source sentences:
text: This extended period of swelling coupled with ambiguity in peak receptivity may have significance in the evolution of such promiscuous sexual behavior (de Waal 1997; Reichert et al. 2002).
text: This behavior is the only place in the world where bonobos clap while grooming, and new individuals introduced to the group learn this behavior (de Waal 2001).