Physiological Constraints in Animal Communication.
My postdoctoral work is focused on how physiological constraints impose limitations and determine variation in behavioral displays. This work is primarily focused on the drumming displays of woodpeckers. Using twitch kinetics, electromyography, and high speed videography, I aim to determine the muscular performance properties necessary for behavioral displays. I am also investigating the role that performance constraints play in limiting and enforcing species recognition in behavioral displays by animals.Additional postdoctoral projects I am working on focus on adaptations that promote the performance of display behaviors in bearded manakins (Genus: Manacus) and echolocation in bats. |
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Early Life Conditions for Brood Parasites & Hosts.
My PhD research focused on brood parasitism by brown-headed cowbirds. Brown-headed cowbirds (Molothrus ater) are generalist brood parasites that obligately lay their eggs in the nests of other species and never build nests of their own. Cowbirds can lay their eggs in the nests of nearly 300 different species, which makes them a model system for understanding how variability in early life conditions can cause changes in development, physiology, and behavior.
My research focuses on a single host species, the prothonotary warbler (Protonotaria citrea), and how variation in each family unit (host parents, host nestlings, and parasitic nestlings) drives the development of functionally-relevant physiology and behavior and the resulting behavioral ecology of brood parasitic cowbirds and their hosts. To measure early life variation in cowbirds, I am currently using methods in neuroscience, endocrinology, genomics, microbiology, and behavioral ecology. The goal of this work is to understand how behavioral variation arises early in development and how it differs with ontogeny, sex, and social milieu.
My research focuses on a single host species, the prothonotary warbler (Protonotaria citrea), and how variation in each family unit (host parents, host nestlings, and parasitic nestlings) drives the development of functionally-relevant physiology and behavior and the resulting behavioral ecology of brood parasitic cowbirds and their hosts. To measure early life variation in cowbirds, I am currently using methods in neuroscience, endocrinology, genomics, microbiology, and behavioral ecology. The goal of this work is to understand how behavioral variation arises early in development and how it differs with ontogeny, sex, and social milieu.
Effect of Brood Parasitism on Parenting Warblers
One aspect of physiology I have been particularly interested in, is the relationship between brood parasitism, circulating corticosterone, and immune function. Raising a brood parasite is energetically costly, and corticosterone, as the primary glucocorticoid hormone, can mediate adaptive physiological and behavioral responses to stressors in birds. Likewise, shifts in the degree of immune responsiveness are also likely to occur when raising energetically costly offspring. We measured these factors and found no tradeoff between corticosterone and immune function, but found that immune function was hampered by brood parasitism and that male warblers responded with particularly high circulating corticosterone (Antonson et al. 2020a).
One aspect of physiology I have been particularly interested in, is the relationship between brood parasitism, circulating corticosterone, and immune function. Raising a brood parasite is energetically costly, and corticosterone, as the primary glucocorticoid hormone, can mediate adaptive physiological and behavioral responses to stressors in birds. Likewise, shifts in the degree of immune responsiveness are also likely to occur when raising energetically costly offspring. We measured these factors and found no tradeoff between corticosterone and immune function, but found that immune function was hampered by brood parasitism and that male warblers responded with particularly high circulating corticosterone (Antonson et al. 2020a).
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Host Use by Brood Parasites
Additionally, I am interested in how adult brood parasites determine a suitable host species for their offspring based on the early life conditions that brood parasitic nestling is likely to experience. Taking an evolutionary phylogenetic approach, my collaborators and I collected data on the physical climate as well as data on specific host traits for nearly 100 species of brood parasites to better understand how these decisions are made in the context of host specialization by a brood parasitic species (Antonson et al. 2020b). Check out this cool video I consulted on for MinuteEarth on Youtube! |
Vocal Development & Early Life Conditions in Songbirds.
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Birds are incredible model organisms for understanding how language develops. Next to humans, songbirds produce some of the most complex vocalizations amongst all organisms. By applying many of the same tools I am using to understand the early life implications of brood parasitism, I am interested in the ontogeny of vocal development and how it builds across an organisms lifespan. I am particularly interested in the genomic and neural mechanisms that drive vocal learning and understanding using zebra finches (Taeniopygia guttata) and red-winged blackbirds (Agelaius phoeniceus) as model systems. For example, colleagues and I recently used methylation ELISAs and ZENK immediate early gene expression correlations to determine how the neural activity of the NCM in embryonic zebra finches responded to hearing their own species' song compared to increasingly phylogenetically-distant species songs (Antonson et al. 2021).
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