Sarah Khalil

Postdoctoral Fellow


Evolution • Sexual Selection • Genomics • Endocrinology

I use an integrative approach to understand how and why birds produce ornamentation, and specifically color. Currently, I study the the endocrine, genomic, and transcriptomic mechanisms of plumage color production in fairywrens, and how this color contributed to reproductive success.


Ph.D, Ecology and Evolutionary Biology, Tulane University
B.S., Biological Sciences, Cornell University


Khalil, S., E. D. Enbody, C. Frankl-Vilches, J. F. Welklin, R. E. Koch, M. B. Toomey, S. Y. W. Sin, S. V. Edwards, M. Gahr, H. Schwabl, M. S. Webster, and J. Karubian (2023). Testosterone coordinates gene expression across different tissues to produce carotenoid-based red ornamentation. Molecular Biology and Evolution 40:msad056.
Hendrix, T. C., F. Fernandez-Duque, S. Toner, L. G. Hitt, R. G. Thady, M. Massa, S. J. Hagler, M. Armfield, N. Clarke, P. Honscheid, S. Khalil, et al. (2023). Behavioural differences between ornamented and unornamented male Red-backed Fairywrens (Malurus melanocephalus) in the nonbreeding season. Emu - Austral Ornithology 0:1–6.
Welklin, J. F., S. M. Lantz, S. Khalil, N. M. Moody, J. Karubian, and M. S. Webster (2023). Photoperiod and rainfall are associated with seasonal shifts in social structure in a songbird. Behavioral Ecology 34:136–149.
Hitt, L. G., S. Khalil, A. Blanchette, M. E. Finkelstein, E. N. K. Iverson, S. C. McClelland, R. Durães Ribeiro, and J. Karubian (2023). Lead exposure is correlated with reduced nesting success of an urban songbird. Environmental Research 227:115711.
Boersma, J., A. McQueen, A. Peters, J. F. Welklin, S. Khalil, R. Quispe, W. Goymann, and H. Schwabl (2022). Unexpected long-term retention of subcutaneous beeswax implants and additional notes on dose and composition from four testosterone implant studies. General and Comparative Endocrinology 330:114124.
Welklin, J. F., S. M. Lantz, S. Khalil, N. M. Moody, J. Karubian, and M. S. Webster (2021). Social and abiotic factors differentially affect plumage ornamentation of young and old males in an Australian songbird. Animal Behaviour 182:173–188.
Khalil, S., J. F. Welklin, K. J. McGraw, J. Boersma, H. Schwabl, M. S. Webster, and J. Karubian (2020). Testosterone regulates CYP2J19-linked carotenoid signal expression in male Red-backed Fairy-wrens (Malurus melanocephalus). Proceedings of the Royal Society B: Biological Sciences 287:20201687.
Sarah Khalil stands in a grassy and hilly landscape
Center Biodiversity Studies & Higher Education

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Golden-cheeked Warbler by Bryan Calk/Macaulay Library