My research focuses on symbiosis, with a particular interest in the evolutionary and ecological consequences of associations between insects and heritable microorganisms. Inherited microbes, those that are transmitted vertically from mother to offspring, can spread within host populations by providing benefits to hosts. Defense against natural enemies is one of the most exciting, and potentially widespread, beneficial effects recently discovered in insect-symbiont associations. In this emerging area of inquiry there is much to discover about the dynamics and distributions of defensive symbionts in natural populations, the genetic features of defensive symbionts, including molecular mechanisms of protection, and the impacts these symbionts exert on populations and communities. This lab uses a multidisciplinary approach, incorporating field studies, experimental laboratory assays and microscopy, as well as molecular, genomic and proteomic tools to investigate symbiont-based defense across scales ranging from molecules to populations and communities.
Aphidius attacking pea aphids. Photograph by Alex Wild.
Lab Personnel
Kyungsun L. Kim, Research Professional II
Post-doctoral Associates
Dr. Vilas Patel
Graduate Students
Clesson Higashi (PhD Entomology)
Nicole Lynn-Bell (PhD Microbiology)
Roy Kucuk (PhD Entomology)
Former Students
Stephanie Weldon (PhD completed 2015)
Adam Martinez, (PhD completed 2015)
Matt Doremus (MS completed 2016)
Laura Kraft (BS/MS completed 2016)
Hannah Dykstra (MS completed 2013)
Undergraduate Researchers
Chris Akin
Will Nichols
Jacob Matta
Courses Taught
ENTO 4000/6000. General Entomology.
Functional anatomy and physiology, behavior, ecology, insects as vectors of pathogens, chemical and biological control of pests.
First-Year Odyssey: Evolution, diversity and importance of insects
First-Year Odyssey: Symbiosis as a source of evolutionary novelty in plants & animals
Selected Publications (For full list see Google Scholar)
Higashi CHV, Barton BT, Oliver KM (2020). Warmer nights offer no respite for a defensive mutualism. J. Animal Ecology 89(8):1895-1905. doi:10.1111/1365-2656.13238
Ives AR, Barton BT, Penczykowski RM, Kim KL, Oliver KM & Radeloff VC (2020) Self-perpetuating ecological-evolutionary dynamics in an agricultural host-parasite system. Nature Ecology & Evolution 4(5):702-711. doi:10.1038/s41559-020-1155-0
Weldon SR, Russell JA & Oliver KM (2020) More is not always better: coinfections with defensive symbionts generate highly variable outcomes. Applied & Environmental Microbiology. 86:e02537-19. https://doi.org/10.1128/AEM.02537-19.
Oliver KM & Perlman SJ (2020). Toxin-mediated protection against natural enemies by insect defensive Symbionts (2020). In Mechanisms underlying microbial symbiosis. Ed. Oliver KM & Russell JA. Advances in Insect Physiology, v58.
Russell JA & Oliver KM (2020). Mechanisms underlying microbial symbiosis. In Mechanisms underlying microbial symbiosis. Ed. Oliver KM & Russell JA. Advances in Insect Physiology, v58
Patel V, Chevignon G, Manzano-Marín A, Brandt JW, Strand MR, Russell JA, Oliver KM (2019). Cultivation-assisted genome of Candidatus Fukatsuia symbiotica; the enigmatic “X-Type” symbiont of aphids. Genome Biology and Evolution 11: 3510-3522. https://doi.org/10.1093/gbe/evz252
Lynn-Bell NL, Strand MR, Oliver KM (2019). Bacteriophage acquisition restores protective mutualism. Microbiology 165(9):985-989. doi:10.1099/mic.0.000816
Oliver KM & Higashi CHV (2019). Variations on a protective theme: Hamiltonella defensa infections in aphids variably impact parasitoid success. Current Opinion in Insect Science 32: 1-7 doi.org/10.1016/j.cois.2018.08.009.
Chevignon G, Boyd BB, Brandt JW, Oliver KM & Strand MR (2018). Culture-facilitated whole-genome sequencing identifies key features underlying strain variation in the heritable facultative symbiont Hamiltonella defensa. Genome Biology & Evolution 10(3) 786-802. doi.org/10.1093/gbe/evy036
Doremus MR, Smith AR, Kim KL, Holder AJ, Russell JA & Oliver KM (2018). Breakdown of a defensive symbiosis, but not endogenous defenses, at elevated temperatures Molecular Ecology 27:8 2138-2151 DOI: 10.1111/mec.14399
Brandt JW, Chevignon G, Oliver KM & Strand MR (2018). Culture of an aphid symbiont demonstrates its direct role in defense against parasitoids. Proc. Royal Soc. Lon. Ser. B. 284(1866) 20171925. http://dx.doi.org/10.1098/rspb.2017.1925
Kraft LJ, Kopko J, Harmon JP & Oliver (2017). Aphid symbionts and endogenous resistance traits mediate competition mediate rival parasitoids. PlosOne. DOI:10.1371/journal.pone.0180729
Martinez AJ, Doremus MR, Kim KL & Oliver KM (2017). Multi-modal defenses in aphid offer redundant protection and increased costs likely impeding a protective mutualism. Journal of Animal Ecology. Epub 5 Jun DOI: 10.1111/1365-2656.12675
Doremus MR & Oliver KM (2017) Aphid heritable symbiont exploits defensive mutualism. Applied & Environmental Microbiology 83:8, doi:10.1128/AEM.03276-16
Martinez AJ, Kim KL, Harmon JP & Oliver KM (2016) Specificity of multi-modal aphid defenses against two rival parasitoids. PlosOne 11(5): e0154670.doi:10.1371/journal.pone.0154670
Oliver KM & Russell JA (2016). Symbiosis, an introduction to. Encyclopedia of Evolutionary Biology. Editor; R. Kliman. Elsevier.
Weldon SR & Oliver KM (2016). Diverse bacteriophage roles in an aphid defensive mutualism.
Advances in Environmental Microbiology. Editor: CJ. Hurst Volume: The Mechanistic Benefits of Microbial Symbionts. Springer, Berlin.
Oliver KM & Martinez AJ (2014). How resident microbes modulate ecologically-important traits of insects. Current Opinion in Insect Science. DOI:10.1016/j.cois.2014.08.001.
Dykstra HR, Weldon SR, Martinez AJ, White J, Hopper K, Heimpel, G, Asplen M, Oliver KM. (2014). Factors limiting the spread of the protective symbiont Hamiltonella defensa in the aphid Aphis craccivora. Applied and Environmental Microbiology. 80:18 doi:10.1128/AEM.01775-14.
Martinez AJ, Ritter SG, Doremus MR & Oliver KM (2014). Aphid-encoded variability in susceptibility to a parasitoid. BMC Evolutionary Biology 14: 127 doi:10.1186/1471-2148-14-127
Martinez AJ, Weldon SR & Oliver KM (2014). Effects of parasitism on aphid nutritional and
Protective symbioses. Molecular Ecology 23:6 1594-1607. doi: 10.1111/mec.12550.
Oliver KM & Russell JA (2013). Defensive symbiosis in the real world—framing studies on the diversity and maintenance of protective bacteria in natural insect populations. Functional Ecology. Published online June 2013: DOI: 10.1111/1365-2435.12133
Russell JA, Weldon S, Smith D, Kim KL, Hu Y, Lukasik P, Doll S, Anastopoulos I, Novin M, and Oliver KM (2013) Uncovering symbiont-driven genetic diversity across North American pea aphids. Molecular Ecology 22: 2045-2059.
Weldon SR, Strand MR & Oliver KM (2013). Phage loss and the breakdown of a defensive
symbiosis. Proceedings of the Royal Society London Series B. 280 (1751)
Oliver KM, Noge K, Huang EM, Campos JM, Becerra JX & Hunter MS (2012) Parasitic wasp responses to symbiont-based defense. BMC Biology 10:11
Oliver, K. M., Degnan, P. H., Burke, G. R. & Moran, N. A. 2010. Facultative symbionts of aphids and the horizontal transfer of ecologically important traits. Ann. Review of Entomology 55, 247–266.
Oliver, K. M., Degnan, P. H., Hunter, M.S. & Moran, N. A. 2009. Bacteriophages encode factors required for protection in a symbiotic mutualism. Science 325, 992-994.
Oliver, K. M. & Moran, N. A. 2009. Defensive symbionts in aphids and other insects in White, J. F. & Torres, M. S. Defensive mutualism in microbial symbiosis. London: Taylor & Francis.
Oliver, K. M., Campos, J., Moran, N. A. & Hunter, M. S. 2008. Population dynamics of defensive symbionts in aphids. Proceedings of the Royal Society of London Series B-Biological Sciences 275, 293-299.
Oliver, K. M., Moran, N. A. & Hunter, M. S. 2006. Costs and benefits of a superinfection of facultative symbionts in aphids. Proceedings of the Royal Society of London Series B-Biological Sciences 273, 1273-1280.
Oliver, K. M., Moran, N. A. & Hunter, M. S. 2005. Variation in resistance to parasitism in aphids is due to symbionts not host genotype. Proceedings of the National Academy of Sciences of the United States of America 102, 12795-12800.
Oliver, K. M., Russell, J. A., Moran, N. A. & Hunter, M. S. 2003. Facultative bacterial symbionts in aphids confer resistance to parasitic wasps. Proceedings of the National Academy of Sciences of the United States of America 100, 1803-1807.