Research
Ketterson and her trainees, with her longtime collaborator and partner
Val Nolan, Jr., have conducted long-term field studies combined with experimental manipulation of free-living
dark-eyed juncos at the
Mountain Lake Biological Station in Virginia since the 1970s. Early in her career, Ketterson focused on differential migration, a pattern of movement in which females migrate farther than males. Ketterson developed the experimental approach of manipulating levels of the hormone
testosterone in free-living birds and comparing behavior, physiology, and fitness to controls in order to study the evolution of
life history trade-offs. She coined the term ‘phenotypic engineering’ to describe this approach. They also exhibited higher reproductive success as a result of extra-pair fertilizations despite lower success of broods that they parent. However, she also found that testosterone-treated males had shorter life spans 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 whether
hormones, which affect multiple target tissues simultaneously and mediate coordinated suites of traits, either constrain or potentiate adaptation. 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 of
biodiversity. As the director of the Environmental Resilience Institute, she leads a team of
Indiana University researchers to prepare the
Hoosier state for the effects of on-going environmental change. The Ketterson research group currently conducts field research at a number of sites throughout the range of
junco species, including in Indiana at Kent Farm on the Indiana University Research and Teaching Preserve, in the Appalachian Mountains in Virginia at the
Mountain Lakes Biological Station, in northwest Wyoming at
Grand Teton National Park, Idaho, South Dakota, Mexico, and Guatemala. The 2013 documentary film project, 'Ordinary Extraordinary Junco: Remarkable Biology from a Backyard Bird' highlights years of research conducted by Ketterson and her colleagues. ==Personal life==
Publications
• 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. • Graham, J.L., Bauer, C.M., Heidinger, B.J., Ketterson, E.D., Greives, T.J. (2019) Early‐breeding females experience greater telomere loss. Molecular Ecology 28 (1), 114–126. • 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. ==References==