Darwinian theory is a powerful tool that allows us to understand the evolution of primate societies. Like all animals, primates are faced with the problems of how to survive, breed and rear offspring. However, primate behaviour is particularly complex. Consequently, the research programme led by Volker Sommer asks how primates organise their social and reproductive strategies to adapt to specific environmental conditions and how these challenges are reflected in their cognitive abilities. Largely based on field studies of monkeys and apes in Asia and Africa, this approach also aims to create awareness for the plight of our closest living relatives, as their existence on this planet is increasingly endangered by human activity. Field research is therefore not only understood as an academic exercise, but includes collaboration with governments, NGOs and local communities to conserve primate habitats.
Volker Sommer's research has wider practical and philosophical implications. It has strengthened interpretations of human existence that are fundamentally informed by the concept of gradualism. This naturalistic paradigm stresses the evolutionary roots of our behaviour and physiology and questions the traditional human/animal dichotomy. Such contemporary Darwinian thinking seeks to incorporate the knowledge about our natural heritage into ethical discourses. In particular, Sommer maintains that evolutionary concepts guide our understanding about who should belong to the "community of equals", i.e., who should be considered to be a person with inalienable rights. Humans have strived to defeat nationalism, racism and sexism. Sommer's research reinforces this cause; in addition, he believes the historic moment has come to overcome a further barrier - that of "speciesism", which justifies discrimination based on species membership.
Thus, Sommer's research led him to conclude that our closest living relatives, the great apes (orangutans, gorillas, chimpanzees and bonobos) should be regarded as persons and granted the fundamental rights to life and freedom. As such, he lobbies to change laws in various European countries, to improve the conditions of apes kept in captivity and to protect their natural environment (Great Ape Project).
Sommer's research also disarms heterosexist prejudices in that it demonstrated the widespread occurrence of same-sex sexual and transgendered behaviour amongst non-human animals, especially non-human primates. Consequently, Sommer has been an outspoken critic of the traditional politically and religiously conservative argument that a gay, lesbian, bisexual or transgendered orientation is "against nature". Sommer's research is often cited when changes of legislation are discussed that aim to improve the rights of the LGBT community.
Sommer's philosophy of "radical idealism" continues a tradition of the enlightenment that is at the heart of UCL's original mission. It is therefore fitting that Sommer is a founding member of the scientific board of the Giordano-Bruno Foundation for Evolutionary Humanism. This German-based think-tank - broadly comparable to the British Humanist Association - promotes a scientific and secular worldview that strives to enable ethical and fulfilling lives on the basis of reason and humanity.
Volker Sommer's research as an evolutionary anthropologist focuses on the ecology, social and sexual behaviour of primates as well as on biodiversity conservation - trying to understand how environmental factors shape the interactions between individuals and social structures. For this, Sommer collaborates with laboratories that conduct nutritional, hormonal and genetic analyses, as well as remote sensing imagery and eco-system analyses.
Research topics include inter- and intra-specific variation of primate social systems (in particular monogamy and polygyny), mechanisms and functions of sexual behaviour (including masturbation, homosexual interactions and life-history patterns), sexual selection processes (including infanticide, paternity certainty and menstrual synchronicity), feeding ecology (including plant foods and insectivory), cognition (in particular, extractive foraging with tools) as well as evolutionary approaches to rituals.
Sommer is internationally renowned for his long-term research with free-ranging monkeys and apes in Africa and Asia. He has studied langur monkeys in Rajasthan / India (since 1981, initially in collaboration with S.M. Mohnot, University of Jodhpur), white-handed gibbons in Thailand's Khao Yai rainforest (since 1989, largely in collaboration with Ulrich Reichard, now at Carbondale University / Illinois), olive baboons in West Africa (since 2000, in collaboration with Caroline Ross, Roehampton University), chimpanzees in Nigeria's Gashaka Gumti National Park (since 2000, as director of the Gashaka Primate Project) as well as in Tanzania's Rubondo National Park (2012-2015, in collaboration with Josephine Msindai).
Of particular importance is currently the "Gashaka Primate Project", situated in the border region between Nigeria and Cameroon, which Volker Sommer founded in the year 2000 and directs ever since. Here, in a remote mixed woodland-rainforest habitat, Sommer built up a permanent research station that enables students (at the level of BSc, MSc, PhD) and researchers (at the level of post-doc and seniour researcher) from across the globe to pursue their individual objectives. Over the course of time, collaborators have come from almost two dozen nations (Argentina, Austria, Cameroon, Canada, France, Germany, Greece, Italy, Ivory Coast, Japan, New Zealand, Nigeria, Poland, Portugal, Spain, Sweden, Switzerland, Taiwan, The Netherlands, United Kingdom, USA) and were or are affiliated with 25 universities (Albert-Ludwigs-Universität Freiburg, American University Yola, California State University Fullerton, Federal University of Technology Bauchi, Federal University of Technology Yola, Gombe State University, Humboldt-Universität Berlin, Ibadan University, Oxford Brookes University, Universidad Complutense de Madrid, Universidade Tecnica de Lisboa, Universität Frankfurt, Universität Würzburg, University College London, University of Alabama at Birmingham, University of California Berkely, University of California Riverside, University of Canterbury / New Zealand, University of Chicago, University of Cocody-Abidjan, University of Copenhagen, University of Maiduguri, Taraba State University, University of St. Andrews, University of Neuchatel), 5 research institutes (Academy of Sciences of the Czech Republic Bron; Deutsches Primatenzentrum, Göttingen; International Institut for Tropical Agriculture, Ibadan; Leibniz-Institut für Zoo- und Wildtierforschung, Berlin; Max-Planck-Institut für Evolutionäre Anthropology, Leipzig), 2 zoological societies (Zoological Society of San Diego; North of England Zoological Society), 4 conservation NGOs (Nigerian Conservation Foundation, WWF-UK, Wildlife Conservation Society Nigeria) plus the Nigeria National Parks Service. In 2013, to encompass its wider remit, the project has been renamed "Gashaka Biodiversity Project" and most of its day to day running is now administered via Chester Zoo / North of England Zoological Society.
- Sommer, V, U Buba, G Jesus, A Pascual-Garrido 2016. Sustained myrmecophagy in Nigerian chimpanzees: Preferred or fallback food? American Journal of Physical Anthropology 162: 328-336
- Sommer, V; A Lowe, T Dietrich 2016. Not eating like a pig. European wild boar wash their food. Animal Cognition 19: 245-249
- Sommer, V; A Lowe, G Jesus, N Alberts, Y Bouquet, DM Inglis, M Peterson, E van Riel, J Thompson, C Ross 2016. Antelope predation by Nigerian forest baboons: Ecological and behavioural correlates. Folia Primatologica 87: 67-90
- Goldstone, LG; V Sommer, N Nurmi, C Stephens & B Fruth 2016. Food begging in wild bonobos (Pan paniscus): assessing relationship quality? Primates 57: 367-376
- Minocher, R & V Sommer 2016. Why do mothers harm their babies? Evolutionary perspectives. Interdisciplinary Science Reviews 41: 335-350
- Sommer, V 2016. Menschenaffen als Personen? Das Great Ape Project im Für und Wider. Pp 9-40 in: M Böhnert, M Wunsch, K Köchy (eds): Philosophie der Tierforschung, Bd.2. Freiburg: Karl Alber
- MacLarnon, AM; V Sommer, A Goffe, J Higham, E Lodge, P Tkaczynski, C Ross 2015. Assessing adaptability and reactive scope: introducing a new measure and illustrating its use through a case study of environmental stress in forest-living baboons. General and Comparative Endocrinology 215: 10-24
- Power, C; V Sommer & I Watts 2013. The Seasonality Thermostat: Female reproductive synchrony and male behaviour in monkeys, Neanderthals and modern humans. PaleoAnthropology pp 33−60
- Pascual-Garrido, A; U Buba, O Allon & V Sommer 2013. Apes finding ants: Predator-prey dynamics in a chimpanzee habitat in Nigeria. American Journal of Primatology 75: 1231-1244
- Allon O, A Pascual-Garrido, V Sommer. 2012. Army ant defensive behaviour and chimpanzee predation success: Field experiments in Nigeria. Journal of Zoology 288: 237-244
- Sommer V, U Buba, G Jesus, A Pascual-Garrido. 2012. Till the last drop. Honey gathering in Nigerian chimpanzees. Ecotropica 18: 55-64
- Pascual-Garrido A; U Buba, G Nodza, V Sommer. 2012. Obtaining raw material: Plants as tool sources for Nigerian chimpanzees. Folia Primatologica 83: 24-44
- Gumnior, M, V Sommer. 2012. Multi-scale, multi-temporal vegetation mapping and assessment of ecosystem degradation at Gashaka Gumti National Park. Nigeria. Research Journal of Environmental and Earth Sciences 4: 397-412
- Sommer V. 2011. Kulturnatur, Naturkultur. Argumente für einen Monismus. Zeitschrift für Kulturphilosophie 5: 9-40
- Sommer V, Caroline Ross. eds. 2011. Primates of Gashaka: Socioecology and Conservation in Nigeria's Biodiversity Hotspot. (Series: Developments in Primatology - Progress and Prospects 35) New York: Springer. 534 pp, 93 figs
- Howarth H, V Sommer, F Jordan. 2010. Visual depictions of female genitalia differ depending on source. BMJ Medical Humanities 36: 75-79
- King, AJ; C Narraway, L Hodgson, A Weatherill, V Sommer, S Sumner. 2010. Performance of human groups in social foraging: The role of communication in consensus decision-making. Biology Letters 7: 237-240
- Higham, JP; Y Warren, J Adanu, U Buba, M MacLarnon, V Sommer, C Ross. 2009. Life on the edge: Life-history of olive baboons at Gashaka-Gumti National Park, Nigeria. American Journal of Primatology 71: 293-304
- Hof, J (photography), V Sommer (text). 2010. Menschenaffen wie wir. Portraits einer Verwandtschaft. / Apes Like Us. Portraits of a Kinship. [Bilingual edition]. Mannheim: EditionPanorama, 192 pp, 110 colour plates
- Sommer V. 2008. Schimpansenland. Wildes Leben in Afrika. Munich: C.H. Beck. 251 pp, 8 colour plates ["Chimpanzeeland. Wild Life in Africa"]
- Sommer V. 2007. Darwinisch denken. Horizonte der Evolutionsbiologie. Stuttgart: Hirzel. 168 pp ["Darwinian Thinking. Horizons of Evolutionary Biology"]
- Sommer V, P Vasey (eds). 2006; paperback edition 2011. Homosexual Behaviour in Animals: Evolutionary Perspectives. Cambridge: Cambridge University Press. 382 pp, 58 figs
- Sommer V, Ulrich Reichard. 2000. Rethinking monogamy: The gibbon case. Pp 159-168 in: P Kappeler (ed), Primate Males: Causes and Consequences of Variation in Group Composition. Cambridge: Cambridge University Press