Staff

I study the intersection between intergroup dynamics, cooperation, and social bonds in chimpanzees and bonobos, our closest living relatives, as windows into our past. I am especially interested in questions like what shapes collective action and the emergence of group-level cooperative actions? How does cooperation and social bond maintenance support costly life history trajectories? And how do individuals navigate social decisions beyond the dyad? I approach these questions by observing wild chimpanzees at two sites I co-direct, the Taï National Park, Côte d’Ivoire and the Moyen-Bafing National Park, Guinea. I also study wild bonobos at the Kokolopori Bonobo Reserve, DR Congo in collaboration with Martin Surbeck. In my studies I combine behavioral data of social interactions and cooperative exchange together with endocrine biomarkers that reflect underlying physiology of these processes.  

20 most recent publications (updated June 2023):

1. Koops, K., Arandjelovic, M., Hobaiter, C., Kalan, A., Luncz, L., Musgrave, S., Samuni, L., Sanz, C., Carvalho, S., (2023) Chimpanzee culture in context: Comment on “Blind alleys and fruitful pathways in the comparative study of cultural cognition”. Physics of Life Reviews 44: 77-80
2. Samuni, L., Langergraber, K.E., Surbeck, M. (2023) Characterization of Pan social systems reveals ingroup out-group distinction and out-group tolerance in bonobos. PNAS 119(26), e2201122119
3. Samuni, L., Lemieux, D., Lamb, A., Galdino, D., Surbeck, M. (2022) Tool use behavior in three wild bonobo communities at Kokolopori. American Journal of Primatology e23342
4. Lemoine, S.*, Samuni, L.*, Crockford, C., Wittig, R.M. (2022) Parochial cooperation in wild chimpanzees: a model to explain the evolution of parochial altruism. Philosophical Transactions of the Royal Society B 377 (1851), 20210149.
5. Wessling, E., Samuni, L., Mundry, R., Pascual, MA., Lucchesi, S., Kambale, B., Surbeck, M. (2022) Evaluating the efficacy of consumer-centric method for ecological sampling: Using bonobo (Pan paniscus) feeding patterns as an instrument for tropical forest characterization. Ecology and Evolution 12 (12), e9606.
6. Péter, H, Laporte, M, Newton-Fisher, N.E., Reynolds, V., Samuni, L., Soldati, A., Vigilant, L., Villioth, J., Zuberbühler, K., Hobaiter, C. (2022)  Recognition of Visual Kinship Signals in Chimpanzees (Pan troglodytes) by Humans (Homo sapiens). Journal of Comparative Psychology 136(4), 255.
7.  Cheng, L., Samuni, L., Lucchesi, S., Deschner, T., & Surbeck, M. (2022) Love thy neighbour: Behavioural and physiological responses to intergroup encounters in male bonobos. Animal Behaviour, 187, 319-330.
8. Badihi, G., Bodden, K., Zuberbühler, K., Samuni, L., Hobaiter, C. (2022) Flexibility in the social structure of male chimpanzees (Pan troglodytes schweinfurthii) in the Budongo Forest, Uganda. Royal Society Open Science 9 (9), 220904.
9. Bruendl, A., Girard-Buttoz, C., Bortolato, T., Samuni, L., Grampp, M., Löhrrich, T., Tkaczynski, P. J., Wittig, R.M., Crockford, C. (2022) Maternal effects on the development of vocal communication in wild chimpanzees. iScience 25 (10), 105152.
10. Carvalho, S., Wessling, E.G., Abwe, E.E., Almeida-Warren, K., Arandjelovic, M., Boesch, C., Danquah, E., Diallo, M.S., Hobaiter, C., Hockings, K., Humle, T., Ikemeh, R.A., Kalan, A., Luncz, L., Ohashi, G., Pascual-Garrido, A., Piel, A., Samuni, L., Soiret, S., Sanz, C., Koops K. (2022) Using nonhuman culture in conservation requires careful and concerted action. Conservation Letters.
11. Samuni, L., Crockford, C., Wittig, R.M. (2021) Group-level cooperation in chimpanzees is shaped by strong social ties. Nature Communications, 12 (1), 1-10.
12. Surbeck, M., Girard-Buttoz, C., Samuni, L., Boesch, C., Fruth, B., Crockford, C., Wittig, R.M., Hohmann G. (2021) Attractiveness of female sexual signaling predicts differences in female grouping patterns between bonobos and chimpanzees. Communications Biology 4, 1119
13. Girard-Buttoz, C., Tkaczynski, P., Samuni, L., Fedurek, P., Gomes, C., Löhrrich, T., Manin, V., Preis, A., Vale, P.D., Deschner, T., Wittig, R.M., Crockford, C. (2021) Early maternal loss affects diurnal cortisol slopes in immature but not mature wild chimpanzees. eLife.
14. McCarthy, M.S., Stephens, C., Dieguez, P., Samuni, L., Després-Einspenner, M.L., Harder, B., Landsmann, A., Lynn, L.K., Maldonado, N., Ročkaiová, Z., Widness, J., Wittig, R.M., Boesch, C., Kühl H.S., Arandjelovic, M. (2021)  Chimpanzee identification and social network construction through an online citizen science platform. Ecology and Evolution, 11(4), 1598-1608.
15. Cheng, L., Lucchesi, S., Mundry, R., Samuni, L., Deschner, T., & Surbeck, M. (2021) Variation in aggression rates and urinary cortisol levels indicates intergroup competition in wild bonobos. Hormones & Behavior, 128, 104914.
16. Mielke, A., Preis, A., Samuni, L., Gogarten, J.F., Lester, J.D., Crockford, C., Wittig, R.M. (2021) Consistency of social interactions in sooty mangabeys and chimpanzees. Frontiers in Ecology and Evolution, 8.
17. Grawunder, S., Uomini, N., Samuni, L., Bortolato, T., Girard-Buttoz, C., Wittig, R.M., Crockford, C. (2021) Chimpanzee modification of vowel-like sounds and voice quality suggest expansion through the hominoid lineage. Philosophical Transactions of the Royal Society B 377(1841), 20200455
18. Samuni, L., Wegdell, F., Surbeck, M. (2020) Behavioural diversity of bonobo prey preference as a potential cultural trait. eLife, 9:e59191
19. Samuni, L.*, Tkaczynski, P.*, Deschner, T., Löhrrich, T., Wittig, R.M., Crockford, C. (2020). Maternal effects on offspring growth indicate post-weaning juvenile dependence in chimpanzees (Pan troglodytes verus). Frontiers in Zoology, 17(1), 1-12.
20. Crockford, C., Samuni, L., Vigilant, L., Wittig, R. M. (2020) Postweaning maternal care increases male chimpanzee reproductive success. Science Advances, 6(38), eaaz5746.