After receiving her doctoral degree, Ketterson was a postdoctoral scholar from 1974 to 1975 atWashington State University working with avian environmental physiologistJames R. King.[1] She was an assistant professor atBowling Green State University from 1975 to 1977 before joining the faculty in the Department of Biology atIndiana University in 1977.[1] Ketterson was appointed as a Distinguished Professor of Biology at Indiana University in 2006.[1] She was also appointed as an affiliated faculty member of the Gender Studies department in 2003 and as a program faculty member of the Cognitive Science department in 2006 at Indiana University.[1]
Ketterson and her trainees, with her longtime collaborator and partnerVal Nolan, Jr., have conducted long-term field studies combined with experimental manipulation of free-livingdark-eyed juncos at theMountain Lake Biological Station in Virginia since the 1970s.[7][8][9] Early in her career, Ketterson focused on differential migration, a pattern of movement in which females migrate farther than males.[10][11]
Ketterson developed the experimental approach of manipulating levels of the hormonetestosterone in free-living birds and comparing behavior, physiology, and fitness to controls in order to study the evolution oflife history trade-offs.[12][13][14] She coined the term ‘phenotypic engineering’ to describe this approach.[12][14] Ketterson's research showed that experimentally-elevated levels oftestosterone increased male aggression, reduced parental care, and increased singing in males.[13] In addition, males given exogenous testosterone were preferred by females inmate choice tests.[15] They also exhibited higher reproductive success as a result of extra-pair fertilizations despite lower success of broods that they parent.[16] However, she also found that testosterone-treated males had shorter life spans[13] and reducedimmune system function.[17] Her research has provided a mechanistic understanding of the fitness consequences of how animals allocate time and energy to competing demands (i.e. reproduction versus survival).
Later, her work explored whetherhormones, which affect multiple target tissues simultaneously and mediate coordinated suites of traits, either constrain or potentiate adaptation.[18][19] This work foreshadowed her interest in addressing limits to organisms' ability to respond to environmental change and the role of hormonally-mediated seasonal timing of behaviors (like reproduction,molt, and migration) in the generation and loss ofbiodiversity. As the director of theEnvironmental Resilience Institute, she leads a team ofIndiana University researchers to prepare theHoosier state for the effects of on-going environmental change.[20]
Kimmitt, A.A., Sinkiewicz, D.M., Ketterson E.D. (2020). Seasonally sympatric songbirds that differ in migratory strategy also differ in neuroendocrine measures. General and Comparative Endocrinology 285, 113250.
Whittaker, D.J., Slowinski, S.P., Greenberg, J.P., Alian O., Winters A.D., Ahmad M.M., Burrell M.J.E., Soini H.A., Novotny M.V., Ketterson, E.D., Theis, K.R. (2019). Experimental evidence that symbiotic bacteria produce chemical cues in a songbird. Journal of Experimental Biology 222 (20), jeb202978.
Kimmitt, A.A., Hardman, J.W., Stricker, C.A., Ketterson, E.D. (2019). Migratory strategy explains differences in timing of female reproductive development in seasonally sympatric songbirds. Functional Ecology 33 (9), 1651–1662.
Reed, S.M., Ketterson, E.D. (2019). Breeding Latitude and Annual Cycle Timing in a Songbird. IU Journal of Undergraduate Research.
Liebgold, E.B., Gerlach, N.M., Ketterson, E.D. (2019). Density‐dependent fitness, not dispersal movements, drives temporal variation in spatial genetic structure in dark‐eyed juncos (Junco hyemalis). Molecular Ecology 28 (5), 968–979.
Singh, D., Reed, S.R., Kimmitt, A.A., Alford, K.A., Ketterson, E.D. (2019). Breeding at higher latitude as measured by stable isotope is associated with higher photoperiod threshold and delayed reproductive development in a songbird. bioRxiv, 789008.
Reichard, D.G., Atwell, J.W., Pandit, M.M., Cardoso, G.C., Price, T.D., Ketterson, E.D. (2019). Urban birdsongs: higher minimum song frequency of an urban colonist persists in a common garden experiment. bioRxiv, 761734.
Needham, K.B., Bergeon Burns, C., Graham, J.L., Bauer, C.M., Kittilson, J.D., Ketterson, E.D., Hahn, T., Greives, T.J., (2019). Changes in processes downstream of the hypothalamus are associated with seasonal follicle development in a songbird, the dark-eyed junco (Junco hyemalis). General and Comparative Endocrinology 270, 103–112.[35]
^"Leadership".Environmental Resilience Institute Part of the Prepared for Environmental Change Grand Challenge. Archived fromthe original on 2018-10-17. Retrieved2018-10-17.
^abKetterson, Ellen D.; Nolan, Val; Cawthorn, Michelle J.; Parker, Patricia G.; Ziegenfus, Charles (2008-06-28). "Phenotypic engineering: using hormones to explore the mechanistic and functional bases of phenotypic variation in nature".Ibis.138 (1):70–86.doi:10.1111/j.1474-919x.1996.tb04314.x.ISSN0019-1019.
