Dr Sam Ellis
Lecturer in Psychology
S.Ellis@exeter.ac.uk
Washington Singer 112
Washington Singer Laboratories, University of Exeter, Perry Road, Prince of Wales Road, Exeter, EX4 4QG, UK
Overview
My broad research interest is in social behavior, how the interactions between individuals combine to affect their fitness and life-history. From ants to human’s individuals interact in complex social systems, these social systems can have important effects on an individual’s behavior, and their ability to survive and reproduce. I’m interested the interaction between these broad global effects, the behavior of individuals, and evolution.
More info about me and my research at: Sam Ellis - Home (weebly.com) .
Qualifications
2007-2010 BSc(Hons) Zoology Univerity of Bristol
2011-2015 PhD Biology University of York
Career
2020-2023. Leverhulme Early Career Research Fellow (project: the evolution of menopasue in toothed whales)
2023-Present. Lecturer in Psychology, University of Exeter
Links
Research group links
Research
Research interests
My broad research interest is in social behavior, how the interactions between individuals combine to affect their fitness and life-history. From ants to human’s individuals interact in complex social systems, these social systems can have important effects on an individual’s behavior, and their ability to survive and reproduce. I’m interested the interaction between these broad global effects, the behavior of individuals, and evolution.
Research projects
Recently my key research topics have been
- The evolution of menopause in toothed whales. I use comparative methods to understand how and why menopause evolves, using toothed whales as a model. Toothed whales are the only mammal group where menopause has evolved multiple times. In partcualr I aim to understand how social factors - particualy interactions between females and their relatives - drive promote this unusual life-history strategy.
- The fitness consquences of social structure. Animals (including humans) live in complex social networks. I am intersted how the position of indivdiuals in their social network affects their ability to succesfully survive and reproduce. I study this question in several systems, including killer whales, primates and European rabbits.
- Statistical and network methods, and their uses. I'm broadly intersted in statsitical methdolology, particualary when applied to analysing networks. I am also intersted in novel uses of network analysis, such as using network analysis to understand social identities.
Publications
Journal articles
Lybkær Kronborg Nielsen M, Ellis S, Towers JR, Doniol-Valcroze T, Franks DW, Cant M, Weiss M, Johnstone RA, Balcomb III KC, Ellifrit DK, et al (In Press). A long post-reproductive lifespan is a shared trait among genetically distinct killer whale populations. Ecology and Evolution
Weiss M, Franks D, Giles DA, Youngstrom S, Wasser SK, Balcom KC, Ellifrit DK, Domenici P, Cant M, Ellis S, et al (In Press). Age and sex influence social interactions, but not associations, within a killer whale pod. Proceedings of the Royal Society B: Biological Sciences
Ellis S, Franks D, Nattrass S, Currie T, Cant M, Giles D, Balcomb K, Croft D (In Press). Analyses of ovarian activity reveal repeated evolution of post-reproductive lifespans in toothed whales. Scientific Reports
Weiss M, Ellis S, Franks DW, Nielsen M, Cant M, Johnstone RA, Ellifrit DK, Balcomb KC, Croft D (In Press). Costly lifetime maternal investment in killer whales. Current Biology
Weiss M, Ellis S, Croft D (In Press). Diversity and consequences of social network structure in toothed whales. Frontiers in Marine Science
Croft D, Weiss M, Lybkær Kronborg Nielsen M, Grimes C, Cant M, Ellis S, Franks DW, Johnstone RA (In Press). Kinship Dynamics: Patterns and Consequences of Changes in Local Relatedness. Proceedings of the Royal Society B: Biological Sciences
Ellis S, Franks DW, Nattrass S, Cant MA, Weiss MN, Giles D, Balcomb KC, Croft DP (In Press). Mortality risk and social network position in resident killer whales: sex differences and the importance of resource abundance. Proceedings of the Royal Society B: Biological Sciences, n/a-n/a.
Preston B, Thompson FJ, Ellis S, Kyambulima S, Croft D, Cant M (In Press). Network-level consequences of outgroup threats in banded mongooses: grooming and aggression between the sexes. Journal of Animal Ecology
Nattrass S, Croft D, Ellis S, Cant M, Weiss M, Wright B, Stredulinsky E, Doniol-Valcroze T, Ford JKB, Balcomb KC, et al (In Press). Post-reproductive killer whale grandmothers improve the survival of their grandoffspring. Proceedings of the National Academy of Sciences of USA
Ellis S, Franks DW, Nattrass S, Cant M, Bradley DL, Giles D, Balcomb K, Croft DP (In Press). Post-reproductive lifespans are rare in mammals. Ecology and Evolution
Hughes EA, Ellis S, Smith JR (2024). Connecting groups and behaviours: a network analysis of identity-infused behaviours. Br J Soc Psychol, 63(1), 205-233. Abstract. Author URL.
Giles DA, Teman SJ, Ellis S, Ford JKB, Shields MW, Hanson MB, Emmons CK, Cottrell PE, Baird RW, Osborne RW, et al (2024). Harassment and killing of porpoises (“phocoenacide”) by fish-eating Southern Resident killer whales (Orcinus orca). Marine Mammal Science, 40(2). Abstract.
Ellis S, Franks DW, Nielsen MLK, Weiss MN, Croft DP (2024). The evolution of menopause in toothed whales. Nature, 627(8004), 579-585. Abstract. Author URL.
Grimes C, Brent LJN, Ellis S, Weiss MN, Franks DW, Ellifrit DK, Croft DP (2023). Postreproductive female killer whales reduce socially inflicted injuries in their male offspring. Current Biology, 33(15), 3250-3256.e4.
Lybkær Kronborg Nielsen M, Ellis S, Weiss MN, Towers JR, Doniol-Valcroze T, Franks DW, Cant MA, Ellis GM, Ford JKB, Malleson M, et al (2023). Temporal dynamics of mother-offspring relationships in Bigg’s killer whales: opportunities for kin-directed help by post-reproductive females. Proceedings of the Royal Society B: Biological Sciences
Ellis S, Cant M, Weiss M, Brent L, Meniri M, Thompson F, Croft D (2022). Patterns and consequences of age-linked change in local relatedness in animal societies. Nature Ecology and Evolution Abstract.
Brask JB, Ellis S, Croft DP (2021). Animal social networks: an introduction for complex systems scientists. Journal of Complex Networks, 9(2), 1-19. Abstract.
Lecheval V, Larson H, Burns DDR, Ellis S, Powell S, Donaldson-Matasci MC, Robinson EJH (2021). From foraging trails to transport networks: how the quality-distance trade-off shapes network structure. Proc Biol Sci, 288(1949). Abstract. Author URL.
Ellis S, Franks DW, Weiss MN, Cant MA, Domenici P, Balcomb KC, Ellifrit DK, Croft DP (2021). Mixture models as a method for comparative sociality: social networks and demographic change in resident killer whales. Behavioral Ecology and Sociobiology, 75(4). Abstract.
Grimes C, Brent L, Weiss M, Franks DW, Balcomb KC, Ellifrit DK, Ellis S, Croft D (2021). The effect of age, sex, and resource abundance on patterns of rake markings in resident killer whales (Orcinus orca). Marine Mammal Science
Burns DDR, Franks DW, Parr C, Hawke C, Ellis S, Robinson EJH (2020). A longitudinal study of nest occupancy, trail networks and foraging in a polydomous wood ant population. INSECTES SOCIAUX, 67(3), 419-427. Author URL.
Weiss M, Franks DW, Brent L, Ellis S, Silk M, Croft D (2020). Common datastream permutations of animal social network data are not appropriate for hypothesis testing using regression models. Methods in Ecology and Evolution
Ellis S, Snyder-Mackler N, Ruiz-Lambides A, Platt ML, Brent LJN (2019). Deconstructing sociality: the types of social connections that predict longevity in a group-living primate. Proceedings of the Royal Society B: Biological Sciences, 286(1917), 20191991-20191991. Abstract.
Doheny-Adams T, Lilley CJ, Barker A, Ellis S, Wade R, Atkinson HJ, Urwin PE, Redeker K, Hartley SE (2018). Constant Isothiocyanate-Release Potentials across Biofumigant Seeding Rates. J Agric Food Chem, 66(20), 5108-5116. Abstract. Author URL.
Madlon-Kay S, Montague MJ, Brent LJN, Eliis S, Zhong B, Snyder-Mackler N, Horvath JE, Skene JHP, Platt ML (2018). Weak effects of common genetic variation in oxytocin and vasopressin receptor genes on rhesus macaque social behavior. American Journal of Primatology
Croft DP, Johnstone RA, Ellis S, Nattrass S, Franks DW, Brent LJN, Mazzi S, Balcomb C, Ford JKB, Cant MA, et al (2017). Reproductive Conflict and the Evolution of Menopause in Killer Whales. Current Biology
Ellis S, Robinson EJH (2016). Internest food sharing within wood ant colonies: resource redistribution behavior in a complex system. Behav Ecol, 27(2), 660-668. Abstract. Author URL.
Ellis S, Robinson EJH (2015). The role of non-foraging nests in polydomous wood ant colonies. PLoS ONE, 10(10). Abstract.
Ellis S, Robinson EJH (2014). Polydomy in red wood ants. Insectes Sociaux, 61(2), 111-122. Abstract.
Ellis S, Franks DW, Robinson EJH (2014). Resource redistribution in polydomous ant nest networks: Local or global?. Behavioral Ecology, 25(5), 1183-1191. Abstract.
Robinson EJH, Franks NR, Ellis S, Okuda S, Marshall JAR (2011). A Simple Threshold Rule is Sufficient to Explain Sophisticated Collective Decision-Making. PLOS ONE, 6(5). Author URL.
Chapters
Risch AC, Ellis S, Wiswell H (2016). Where and why? Wood ant population ecology. In (Ed) Wood Ant Ecology and Conservation, 81-105. Abstract.
Maeder A, Cherix D, Bernasconi C, Freitag A, Ellis S (2016). Wood ant reproductive biology and social systems. In (Ed) Wood Ant Ecology and Conservation, 37-50. Abstract.
External Engagement and Impact
Editorial responsibilities
Associate Editor Behavioral Ecology and Sociobiology
Teaching
Modules
2023/24
Supervision / Group
Postgraduate researchers
- Libby Chapman
- Charli Grimes
- Ingerid Helgestad
- Rachel John
- Natasha Marosi
Alumni
- Mia Lybkær Kronborg Nielsen
