of Victoria
Accepting MA/PhD students
PhD University of Leipzig/ IMPRS
Biological anthropology, primate behavioural ecology, conservation and communication, animal cultures, tool use, bioacoustics, camera trapping
Accepting MA/PhD students interested in Primate and Predation Pressure & Comparative Great Ape Locomotion Projects (see below)
I am a field-based primatologist, primarily interested in the social and ecological drivers of behavioural flexibility in wild great apes, and what this can tell us about hominin evolution using a comparative perspective. In particular, I research behavioural flexibility as it relates to the domains of communication, tool use, foraging ecology and nonhuman cultural traditions. I am also interested in improving our understanding of the behavioural strategies primates can use to adapt and survive in increasingly anthropogenic environments and under climate change. To date, my research has focussed on wild populations of great apes across Africa, where I also work on improving remote methods for studying these animals in the field, such as passive acoustic monitoring and camera trapping. This research has led me to expand my interest in great apes to the behavioural ecology and conservation of other nonhuman primate species as well.
I currently collaborate with directors of multiple African great ape field sites with the aim of expanding future work to also include wild orangutans. I remain an affiliated researcher with the Pan African Programme: the Cultured Chimpanzee (PanAf), a Scientific Moderator of Chimp&See, the PanAf’s citizen science project, and head of a project investigating chimpanzee accumulative stone throwing in West Africa. I encourage any prospective students or postgraduates to contact me directly if you are interested in working on any of my current projects or have your own project ideas related to my interests.
Spring 2024
Multiple recent publications have examined the effects of human impact and environmental variability on chimpanzee behavioural and cultural diversity in collaboration with PanAf colleagues based around the world. This research is currently being expanded upon to investigate large-scale patterns in genetic diversity and connectivity across PanAf sites and how this might influence behavioural divergence among chimpanzee populations. My ongoing collaborations with the PanAf also include examining chimpanzee diet and microbiome diversity with respect to tool use behaviours. I aim to continue building on our PanAf behavioural and cultural diversity research by creating an openly accessible behavioural database for wild chimpanzees that can be continuously updated and shared with researchers, NGOs and international government organizations in order to promote a more inclusive approach to chimpanzee conservation.
Previous publications on this behaviour have demonstrated that chimpanzee AST is rare among wild populations and may represent a new cultural behaviour found only in West Africa. My recent publication in collaboration with acoustic engineers (PRISM lab, CNRS & Aix-Marseille University) showed that chimpanzees choose tree species that are optimal for sound production and therefore the behaviour appears important for communication. I am currently conducting additional spatial and behavioural analyses of chimpanzee AST from data collected in 2017. These data will ultimately be compared to PanAf data collected in 2014 at the same site, also using camera traps, as well as a genetic census in collaboration with Mimi Arandjelovic (Max Planck Institute for Evolutionary Anthropology). Additional ongoing projects include 3D modeling of AST sites to describe and digitally preserve the visual, long-lasting components to this behaviour that persist in the landscape.
Future projects include investigating landscape archaeological signatures of AST in collaboration with Lydia Luncz (Max Planck Institute for Evolutionary Anthropology) and field experiments to examine potential symbolic aspects to this behaviour in collaboration with Klaus Zuberbühler (University of Neuchâtel). I am also interested in researching the kinematics of chimpanzee throwing and comparing this to other hominids, both living and extinct. My research on chimpanzee AST is made possible with the continued support of Chimbo, an NGO based in Boé, Guinea-Bissau.
I am interested in improving remote methods used to monitor and observe wild primates in the field. I have published on the use of passive acoustic monitoring for primates and the behavioural effects of camera trapping on great apes and other wildlife. Current projects include collaborations with computer scientists (Laboratory for BioSignal Processing, Leipzig University of Applied Sciences & University of Osnabrück) to apply deep learning algorithms for improving automated detection and classification of chimpanzee sounds from continuous audio recordings. My affiliation with the PanAf also includes being a scientific moderator of Chimp&See, where citizen scientists help us to classify thousands of camera trap videos recorded at PanAf sites, where I also lead various mini-projects.
Leopards are one of the most abundant natural predators for all primates, big and small, across Africa but we know little about their direct effects on primate behaviour despite predation being considered one of the major selection pressures driving primate evolution. I am currently leading a mini-project on Chimp&See to identify individual leopards caught on camera traps to obtain precise densities across all PanAf sites, where we will eventually test whether leopard abundance affects primate species diversity as well as their spatio-temporal activity patterns and behaviour.
I am beginning a project to evaluate the degree of bipedalism observed in wild chimpanzees, bonobos and gorillas using camera trap videos to test multiple hypotheses regarding the origins and adaptive benefits of bipedalism, given that our species is the only obligate biped living today. I will be applying state-of-the-art methods for quantifying bipedal postures and movement, namely DensePose software, which has recently been adapted for use with nonhuman great apes in a collaboration between the PanAf and Facebook AI. In addition to PanAf data, this project includes collaborations with bonobo and gorilla field site directors Gottfried Hohmann, Barbara Fruth (Liverpool John Moores University), Martin Surbeck (Harvard University) and Martha Robbins (Max Planck Institute for Evolutionary Anthropology).
I am embarking on a project to compare bonobos, chimpanzees and orangutans with respect to vocalizations, object-instrumental signals and tool use in the communication domain: a promising area for identifying cultural traditions and social customs in wild great apes that have otherwise been understudied to date. So far, comparative cross-site analyses of chimpanzee food calls are ongoing with Katie Slocombe (University of York).
Kalan AK, Kulik L, Arandjelovic M, et al. (2020). Environmental variability supports chimpanzee behavioral diversity. Nature Communications 11, 4451 (2020). https://doi.org/10.1038/s41467-020-18176-3
Boesch C, Kalan AK, Mundry R, et al. (2020). Chimpanzee ethnography reveals unexpected cultural diversity. Nature Human Behaviour https://doi.org/10.1038/s41562-020-0890-1
Kalan AK (2019) Evidence for sexual dimorphism in chimpanzee vocalizations: A comparison of male and female call production and acoustic parameters. In: Celebrating 40 Years of Research at the Taï Chimpanzee Project. Pg. 410-421. Eds. Boesch C, Wittig R, Crockford C, Vigilant L, Deschner T & Leendertz F. https://doi.org/10.1017/9781108674218.026