A dyadic brain model of ape gestural learning, production and representation

It has been argued that variation in gesture usage among apes is influenced either by differential sampling of an innate 'gesture space' (Hobaiter and Byrne in Anim Cogn 14:745-767, 2011) or through the 'mutual shaping of behavior' (Halina et al. in Anim Cogn 16(4):653-666, 2013) referred to as ontogenetic ritualization. In either case, learning must play some role in how individuals come to use particular gestures-either through reinforcement within the set of innately specified gestures, or through the ritualization of some action following periods of direct interaction between pairs of individuals. Building on a prior computational model detailing learning during ontogenetic ritualization (Arbib et al. in Philos Trans R Soc Lond B Biol Sci 369(1644):20130414, 2014, https://doi.org/10.1098/rstb.2013.0414 ), we here present a single integrative dyadic brain model (simulating selected brain and body dynamics of two interacting apes) that can account for many observed gestural patterns, while additionally showing that both of the claimed paths toward competent gestural performance are predicated on social influences-even the usage of inherited gestures demands learning about others' behaviors.