Hunting and meat-eating behaviors in nonhuman primates, particularly the genus Pan, have been intensely studied from a range of perspectives in hominin evolution such as the evolution of cooperation (Isaac 1978; Boesch and Boesch 1989; Mitani 2009; Samuni et al. 2018), sexual division of labor (Marlowe 2007; Gilby et al. 2017), and energetics of encephalization (Aiello and Wheeler 1995; Moore et al. 2017). Compared to the study of hunting behaviors by chimpanzees (Pan troglodytes) over the last half century (e.g., Boesch and Boesch 1989; Hosaka et al. 2001; Mitani et al. 2002; Newton-Fisher et al. 2002; Gilby 2006), observations of hunting and meat-eating by bonobos (Pan paniscus) are rare (Badrian and Malenky 1984; Ihobe 1992; Bermejo et al. 1994; White 1994; Fruth and Hohmann 2002) and thus it had long been considered that these behaviors were far less common among bonobos. However, recent studies at sites established since the 2000s demonstrate a wider range of variation in prey preferences and higher frequency of meat-eating among bonobos (LuiKotale: Hohmann and Fruth 2008; Surbeck and Hohmann 2008; Surbeck et al. 2009; Fruth and Hohmann 2018; Iyondji: Sakamaki et al. 2016; Iyema: Wakefield et al. 2019; Kokolopori: Samuni et al. 2020).

Conclusion

Considering both fecal analysis and direct observational data since the 1970s, the frequency of meat-eating by bonobos at Wamba was lower than that at other sites and the prey targets were mainly anomalures (Anomalurus derbianus and/or A. beecrofti). Before the interruption of fieldwork in 1996 due to political unrest, bonobos were mainly observed at artificial feeding sites, whereas after the resumption of fieldwork in 2003 they were observed in the forest without artificial feeding. This change in the observation condition did not appear to affect the frequency of meat-eating by bonobos at Wamba.
At some bonobo study sites such as LuiKotale and Kokolopori, bonobos ate meat more frequently than at Wamba considering fecal analysis and direct observational data. At LuiKotale, a wider range of prey was observed including ten species of mammals. Bonobos may eat meat more frequently than previously thought, and there may not be a big difference in the range of the target species of chimpanzees and bonobos. Bonobos have been observed to surround the owner of the meat and engage in begging behaviors and meat transfer. These behaviors suggest that meat is a highly valued food for bonobos as in the case for chimpanzees even though meat-eating is infrequent.
Chimpanzees often hunt in groups and they sometimes actively pursue and hunt prey together; however, bonobos typically hunt prey alone opportunistically. The difference in their hunting techniques may correspond to differences in the behavioral patterns of the species being hunted. Interspecific differences between bonobos and chimpanzees were observed in food sharing, which may be due to differences in the frequency of hunting, the size of prey species and the social relationships between the two species, such as the relatively higher status of females compared to males in bonobos. Further research is needed to elucidate regional differences in hunting and meat-eating behavior by bonobos as well as differences with chimpanzees.