Bonobo food sharing with outside groups tied to concealed ovolution, individuation and vocalization

One behavioral pattern serving as a starting point for the evolution of societal levels is the genus Pan’s “protolanguage” (Moffett 2013), reflected in specific elements of their distance vocalization coding group identity (Crockford et al. 2004). With this in mind, Moffett (2013) has timed emergence of social identity beyond individual recognition after the Pan-Homo split.

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 we do have evidence that cooperation between unrelated females may override genetic ties (Parish and de Waal 2000) and lead to a social network based on reciprocity and mutuality rather than kinship (Moscovice et al. 2017). Second, the social selection hypothesis, which postulates the occurrence of competition for being chosen as either a social partner or a mate (West-Eberhard 1983), could also explain tolerant sharing with unfamiliar individuals. This hypothesis finds support in the bonobos’ concealed ovulation, making mate guarding and male-male competition less effective than in other species, and giving way to female choice (Douglas et al. 2016; Furuichi et al. 2012; Reichert et al. 2002).

https://link.springer.com/article/10.1007/s12110-018-9311-9