Abstract
Bonobos are typically portrayed as more socially tolerant than chimpanzees, yet the current evidence supporting such a species-level categorization is equivocal. Here, we used validated group-level co-feeding assays to systematically test expressions of social tolerance in sixteen groups of zoo- and sanctuary-housed bonobos and chimpanzees. We found that co-feeding tolerance substantially overlaps between the species, thus precluding categorical inference at the species level. Instead, marked differences were observed between groups, with some bonobo communities exhibiting higher social tolerance than chimpanzee communities, and vice versa. Moreover, considerable intergroup variation was found within species living in the same environment, which attests to Pan's behavioral flexibility. Lastly, chimpanzees showed more tolerance in male-skewed communities, whereas bonobos responded less pronounced to sex-ratio variation. We conclude that the pervasive dichotomy between the tolerant bonobo and the belligerent chimpanzee requires quantitative nuance, and that accurate phylogenetic tracing of (human) social behavior warrants estimations of intraspecific group variation.
| Original language | English |
|---|---|
| Article number | 108528 |
| Pages (from-to) | 1-12 |
| Number of pages | 12 |
| Journal | iScience |
| Volume | 26 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 15 Dec 2023 |
Bibliographical note
Publisher Copyright:© 2023 The Authors
Funding
We are indebted to fruitful collaborations with all involved zoos and sanctuaries. We also thank Jonas Torfs, Ilke Fromont, Sanne van Donink, Emile Bryon, Zoë Goldsborough, Nora Slania, Yana Robeyns, Kim Vermeulen, and Heritier Izansone for assistance in data collection. We further thank Roger Mundry for statistical advice. E.J.C.v.L. was funded by the European Union under ERC Starting Grant no. 101042961 – CULT_ORIGINS. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. Conceptualization, E.J.C.v.L. N.S. and J.M.G.S.; methodology, E.J.C.v.L. N.S. and J.M.G.S.; investigation, E.J.C.v.L. N.S. J.S.B. S.K. and S.N.; writing – original draft, E.J.C.v.L.; writing – review and editing, E.J.C.v.L. N.S. J.S.B. S.K. S.N. Z.C. M.E. and J.M.G.S.; funding acquisition, E.J.C.v.L. N.S. Z.C. and J.M.G.S.; supervision, E.J.C.v.L. N.S. Z.C. and J.M.G.S. The authors declare no competing interests. We are indebted to fruitful collaborations with all involved zoos and sanctuaries. We also thank Jonas Torfs, Ilke Fromont, Sanne van Donink, Emile Bryon, Zoë Goldsborough, Nora Slania, Yana Robeyns, Kim Vermeulen, and Heritier Izansone for assistance in data collection. We further thank Roger Mundry for statistical advice. E.J.C.v.L. was funded by the European Union under ERC Starting Grant no. 101042961 – CULT_ORIGINS. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them.
| Funders | Funder number |
|---|---|
| European Research Executive Agency | |
| European Commission | |
| European Research Council | 101042961 |
Keywords
- Biological sciences
- Ethology
- Zoology