For a better experience, click the Compatibility Mode icon above to turn off Compatibility Mode, which is only for viewing older websites.

Sean O'Donnell, PhD

Sean O'Donnell, PhD

Department of Biodiversity, Earth and Environmental Science
Department of Biology


  • PhD Entomology/Zoology, Univ. Wisconsin-Madison, 1993
  • MS Entomology, Univ. Wisconsin-Madison, 1989
  • BS Biology, St. Joseph’s University, 1986

Research Interests:

  • Brain plasticity and the evolution of brain structure
  • Social behavior and division of labor, especially of eusocial Hymenoptera
  • Thermal ecology and thermal physiology
  • Network models of social group organization
  • Behavior and ecology of bird-army ant interactions
  • Human-safe insecticides


Sean O’Donnell has been teaching and doing research at the university level since 1996. His current research focuses on relating brain evolution and brain plasticity to ecology and behavior, evolution and development of animal thermal physiology, complex social and ecological group interactions, and the evolution of body shape and size. Study subjects include diverse social insects and arthropods (bees, ants, wasps, termites, and social spiders), and Neotropical birds. He collects data mainly in the Neotropics but with additional field work in Israel. Sean’s teaching interests span ecology, evolution and animal behavior, including tropical field courses. He regularly works as an expert science consultant with natural history film crews.

Selected Publications:

O'Donnell, S. & C. Gallen. 2022. The evolution of head size hypoallometry: biomechanical implications and brain investment as a possible cause. Arthropod Structure and Development 101175. DOI: 10.1016/j.asd.2022.101175

Fiocca, K., R. Congdon, & S. O'Donnell. 2022. Body size correlations with female aggression and physiology suggest pre-adult effects on caste in an independent-founding eusocial paper wasp (Mischocyttarus pallidipectus Hymenoptera: Vespidae). Ethology Ecology and Evolution. DOI: 10.1080/03949370.2021.2024270.

Caponera, V., L. Avilés, M. Barrett, & S. O'Donnell. 2021. Behavioral attributes of social groups determine the strength and direction of selection on neural investment. Frontiers in Ecology and Evolution 9: 733228.

O'Donnell, S., S.J. Bulova, & M. Barret. 2021. Experience-expectant brain plasticity corresponds to caste-specific abiotic challenges in dampwood termites (Zootermopsis angusticollis and Z. nevadensis). Science of Nature 108: 57

Barrett, M., S. Schneider, P. Sachdeva, A. Gomez, S. Buchmann, & S. O'Donnell. 2021. Neuroanatomical differentiation associated with alternative reproductive tactics in male arid land bees, Centris pallida and Amegilla dawsoni. Journal of Comparative Physiology A 207: 497-504.

O'Donnell, S., S. Bulova, V. Caponera, K. Oxman, & I. Giladi. 2020. Species differ in worker body size effects on critical thermal limits in seed-harvesting desert ants (Messor ebeninus and M. arenarius). Insectes Sociaux 67: 473-479.

Fiocca, K., K. Capobianco, E. Fanwick, K. Moynahan, R. Congdon, P. Zelanko, S. O'Donnell, D. Velinsky. 2020. Reproductive physiology corresponds to adult nutrition and task performance in a Neotropical paper wasp: a test of dominance-nutrition hypothesis predictions. Behavioral Ecology and Sociobiology 74: 114.

Soare T.W., A. Kumar, K.A. Naish & S. O'Donnell. 2020. Multi-year genetic sampling indicates maternal gene flow via colony emigrations in the army ant Eciton burchellii parvispinum. Insectes Sociaux 67: 155-166.

Barrett, M. V. Caponera, C. McNair, S. O’Donnell, & D.R. Marenda. 2020. Potential for use of erythritol as a socially- transferrable ingested insecticide for ants (Hymenoptera: Formicidae). Journal of Economic Entomology 113: 1382-1388.