My dissertation research is focused on understanding how plumage ornaments evolve in female birds, but I am broadly interested in research questions at the intersection of mechanisms of trait evolution and their evolutionary consequences. I am particularly interested in using cutting-edge techniques to investigate wild populations that exhibit properties which are at odds with current theory. My graduate research focuses on how color has evolved in the White-shouldered Fairywren (Malurus alboscapulatus), a species of grassland bird endemic to New Guinea.
Behavioral consequences of elaborate ornamentation in birds
The elaborate coloration of many male animals has inspired biologists to study the function of elaborate male ornaments since Darwin and Wallace. That male ornaments face sexual and social selection pressures is now fundamental in evolutionary biology, but what function, if any, female ornaments serve is comparatively less known. For my Ph.D. research, I study a unique species of bird that varies between subspecies by female, but not male, coloration. This provides a system well suited for studying the function of female coloration in driving population divergence. I experimentally test the function of female ornaments using controlled song and mount playback trials to free flying birds and compare the role of testosterone in mediating aggression and ornamentation between the sexes (in prep).
Brouwer, L., M. van de Pol, N. H. Aranzamendi, G. Bain, D. T. Baldassarre, D. Colombelli-Négrel, E.D. Enbody, K. Gielow, M. L. Hall, A. E. Johnson, J. Karubian, S. A. Kingma, S. Kleindorfer, M. Louter, R.A. Mulder, A. Peters, S. Pruett-Jones, K. A. Tarvin, D.J. Thrasher, C.W. Varian-Ramos, M.S. Webster, A. Cockburn. 2017. Multiple hypotheses explain variation in extra-pair paternity at different levels in a highly variable avian family. Molecular Ecology. 26:6717–6729. doi: 10.1111/mec.14385
Ornament production in birds
Bird feathers are a complex structure that use a relatively limited arsenal of mechanisms to produce the astounding variety of color found in birds. I use photospectroscopy and electron microscopy to characterize color signals in birds and link them to their underlying structural component. I am interested in how different organization of feather tissues produces color, but more importantly how these underlying characteristics can face selective pressures and lead to individual and species level variation.
Enbody, E.D., Lantz S.M., and J. Karubian. 2017. Production of plumage ornaments among males and females of two closely related tropical passerine bird species. Ecology and Evolution. 00:1-11 and PDF. doi: 10.1002/ece3.3000
Proximate mechanisms of plumage coloration
Female ornaments are influenced not only by selective forces acting on the traits, but also by the genetic mechanisms that produce that phenotype. I whole genome sequencing and transcriptomics to study the mechanisms that lead to variation in both female coloration and sexual dichromatism. My study using the White-shouldered Fairywren as an exemplar will investigate what genome wide characteristics are associated with population level variation in sexual dichromatism and what genes are differentially expressed when producing color in different female phenotypes. This research was funded by an NSF Dissertation Improvement Grant and data from the project is currently being analyzed.
Engagement in conservation
My research is has a strong tropical focus, which often takes place in regions where the local communities have close social and economic ties to the environment where they live. New Guinea is a particularly biodiverse location where more than 5% of the worlds species are present on less than 1% of the world’s landmass. The relatively small populace and remoteness of the country has led to some of the most pristine wilderness in the world, but these are increasingly facing threats from anthropogenic pressure in population growth, climate change, and exploitation for fossil fuels and agriculture. We work closely with local communities where we work to advocate for and develop a locally led group dedicated to grassland conservation. The goal of this project is to support the idea that conservation is not just for the community, but by the community as well. To read more about our conservation initiatives in PNG, follow this link