• Chair and Professor of Biology


  • Bachelor of Arts, Hendrix College, 1986
  • Master of Science, University Arkansas, 1991
  • Doctor of Philosophy, University South Florida, 1998
  • Post-doc, University of Chicago, 1998-2000


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Evolutionary and behavioral ecology, including signaling and communication, sexual and social selection, social evolution, and life history evolution.

I am interested in the ways in which selection shapes social behavior, and my research and much of my teaching centers on this broad area of inquiry. I teach BIOL 318: Evolution, BIOL 309: Ornithology, BIOL 315: Behavioral Ecology, and first-year and upper-level seminars on the evolution of sociality (FYSP 181; BIOL 406). I’ve also taught BIOL 100: Organismal Biology, and may teach one or more of our core/introductory biology classes in the future. You can find recent syllabi for these courses listed below.

As of this writing (August 2014) I have two primary research foci, which are described below.

Other Stuff

 I occasionally work on other projects, depending on student interests. In past lives, I worked on extra-pair mating and social organization in Australian fairy-wrens in Stephen Pruett-Jones’ lab, and on various aspects of blue jay ecology.

Signaling Function of Ornamental Coloration in American Goldfinches

Most of my research centers on the signaling function of ornamental coloration of American goldfinches, and I do that work in collaboration with Troy Murphy of Trinity University in San Antonio and our respective students. American goldfinches are colorful songbirds that exhibit bright yellow and black plumage and orange bills during the breeding season. Males have extensive yellow plumage, black wings, and a black cap. Colorful plumage is much less extensive in females, but they do have small patches of yellow plumage. Bills of both sexes become very orange during the breeding season, and the quality of the color is similar between the sexes. Moreover, goldfinch bill color is dynamic – it has the capacity to change in response to perturbations on the order of hours.

We have found that bill color of female goldfinches is used to mediate competitive interactions with other females, but males don’t pay attention to female bill color and apparently neither sex pays attention to male bill color. Goldfinch bill color appears to function as a reliable signal of competitive status because it is condition dependent – bill color is correlated with immunocompetence and circulating testosterone in females, and with recent stress in both males and females. Curiously, bill color doesn’t appear to reflect blood parasite infection status, which might be expected if it is a general signal of overall health. We currently are investigating whether the dynamic component of bill color specifically signals social sources of stress, such as that associated with losing competitive interactions, as opposed to more general sources of stress such as energetic stress. Goldfinch publications are listed below.

Heterospecific Alarm Call Recognition in Eastern Gray Squirrels

I recently initiated a project exploring heterospecific alarm call recognition in eastern gray squirrels (a “heterospecific” call is a call given by a different species). Many species emit alarm calls when they detect a predator. In most cases, alarm calls seem to be directed either toward social group mates (usually relatives), or to the predator itself as a signal that it has been detected and is unlikely to make a meal of the wary caller. However, because alarm calls generally provide information about the presence of a predator, individuals that are not the intended recipients of alarm calls can make use of that information. For example, squirrels share their environment with many other species that are more or less susceptible to the same predators that prey on squirrels. If one of those other species detects a predator and emits an alarm call, a squirrel could benefit from that information and respond accordingly with increased vigilance or escape behavior. Thus, we expect individuals to “eavesdrop” on the alarm calls of other individuals with which they share predators, regardless of what species those other individuals belong to. However, we also expect individuals to use some degree of discretion when attending to heterospecific vocalizations: if a squirrel responds to every squeak, chirp, and buzz emitted by other individuals in its environment, it may waste valuable time that could otherwise be spent feeding or reproducing. Thus, there should be an optimal degree of attentiveness to heterospecific alarm calls, and that optimum should vary with the degree of predator overlap between the caller and receiver. Of course, since learning plays a role in alarm call recognition, familiarity with the calls will influence the degree to which an individual’s attentiveness to a given call is near the optimum.

My students and I have used playback experiments to show that squirrels attend to the alarm calls of American robins (click here for the paper). They even pay some attention to the alarm calls of unfamiliar allopatric European blackbirds – close relatives of robins that have similar features of alarm call acoustic structure – although they do not respond to them as regularly. This is interesting because it suggests that squirrels attend to specific acoustical properties of familiar alarm calls and extrapolate that attention to unfamiliar calls with similar structure. Perhaps they do this because they are fooled by the unfamiliar but similar alarm calls, or perhaps they do it because the cost of being wrong about whether or not the unfamiliar call really is a robin alarm call could be deathly high.

We are currently testing whether squirrels are able to discriminate between familiar heterospecific alarm calls that contain useful information and those that contain unimportant information. Chickadees give “referential” alarm calls – they alter the structure of their alarm calls depending on the predator context that elicits them. Chickadees give alarm calls with lots of d-notes (think “chick-a-dee-dee-dee”) in response to small, fast predators such as screech owls, and give calls with fewer d-notes in response to large slow predators such as red-tailed hawks. To a chickadee, a small predator is much more dangerous than a big one, and other chickadees respond intensely to alarm calls with lots of d-notes. However, squirrels aren’t really vulnerable to small predators like screech owls, but they are very vulnerable to large hawks and owls. We are conducting playback experiments to determine whether squirrels attend to chickadee calls that signal the presence of large predators, while ignoring chickadee calls that signal the presence of small predators.


(* denotes undergraduate student)       Updated August 2014

 *Lumpkin D C, Murphy T G, and Tarvin K A. 2014. Blood parasite infection differentially relates to carotenoid-based plumage and bill color in the American goldfinch. Ecology and Evolution DOI: 10.1002/ece3.1164. pdf

Murphy T G, *West J A, *Pham T T, *Cevallos L M, *Simpson R K, and Tarvin K A. 2014. Same trait, different receiver response: Unlike females, male American goldfinches do not signal status with bill colour. Animal Behaviour 93: 121-127. pdf

*Pham T T, *Queller P S, Tarvin, K A, and Murphy T G. 2014. Honesty of a dynamic female aggressive status signal: baseline testosterone relates to bill color in female American goldfinches. Journal of Avian Biology 45: 22-28. pdf

Smith K G, Tarvin K A and Woolfenden G E. 2013. Blue Jay (Cyanocitta cristata), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology. http://bna.birds.cornell.edu/bna/species/469; doi:10.2173/bna.469.

*Getschow C M, *Rivers P, *Sterman S, *Lumpkin D C, and Tarvin K A. 2013. Does gray squirrel Sciurus carolinensis response to heterospecific alarm calls depend on familiarity or acoustic similarity? Ethology 19, 983-992. pdf

*Rosenthal M F, Murphy T G, Darling N, and Tarvin K A. 2012. Ornamental bill color rapidly signals changing condition. Journal of Avian Biology 43: 553-564. pdf

Tarvin K A and Murphy T G. 2012. It isn’t always sexy when both are bright and shiny: considering alternatives to sexual selection in elaborate monomorphic species. Ibis: The International Journal of Avian Science 154: 439–443. pdf

*Kelly R J, Murphy T G, Tarvin K A, and Burness G. 2012. Carotenoid-based ornaments of female and male American goldfinches (Spinus tristis) show sex-specific correlations with immune function and metabolic rate. Physiological and Biochemical Zoology 85: 348–363. pdf

Murphy T G, *Rosenthal M F, Montgomerie R, and Tarvin K A. 2009. Female American goldfinches use carotenoid-based bill coloration to signal status. Behavioral Ecology 20: 1348-1355. pdf

Webster M S, Tarvin K A, Tuttle E M, and Pruett-Jones S. 2007. Promiscuity drives sexual selection in a socially monogamous bird. Evolution 61: 2205-2211. pdf

*Rosen R F and Tarvin K A. 2006. Sexual signals of the male American goldfinch. Ethology 112: 1008-1019. pdf

Tarvin K A. 2006. Polymorphic microsatellite loci from the American goldfinch (Carduelis tristis) and their cross-amplification in a variety of passerine species. Molecular Ecology Notes 6: 470-472. pdf

Tarvin K A, Webster M S, Tuttle E M, and Pruett-Jones S. 2005. Genetic similarity of social mates predicts the level of extra-pair paternity in splendid fairy-wrens. Animal Behaviour 70: 945-955. pdf

Webster M S, Tarvin K A, Tuttle E M, and Pruett-Jones S. 2004. Reproductive promiscuity in the splendid fairy-wren: Effects of group size and auxiliary reproduction. Behavioral Ecology 15 (6): 907-915. pdf

Garvin M C, Tarvin K A, Smith J, Ohajuruka O A, and Grimes S D. 2004. Patterns of West Nile virus infection in Ohio blue jays: Implications for initiation of the annual cycle. American Journal of Tropical Medicine and Hygiene 70 (5): 566-570. pdf

Garvin M C, Tarvin K A, Stark L M, Woolfenden G E, Fitzpatrick J W, and Day J F. 2004. Arboviral infection in two species of wild jays (Aves: Corvidae): Evidence for population impacts. Journal of Medical Entomology 41: 215-225. pdf

Tarvin K A and Garvin M C. 2002. Habitat and nesting success of Blue Jays: Importance of scale. Auk 119 (4): 971-983. pdf

Driskell A C, Pruett-Jones S, Tarvin K A, and *Hagevik S. 2002. Evolutionary relationships among blue- and black-plumaged populations of the white-winged fairy-wren (Malurus leucopterus). Australian Journal of Zoology 50: 581-595. pdf

Zelano B, Tarvin K A, and Pruett-Jones S. 2001. Singing in the face of danger: The anomalous Type II song of the splendid fairy-wren. Ethology 107: 201-216. pdf

Pruett-Jones S and Tarvin K A. 2001. Aspects of the ecology and behaviour of White-winged Fairy-wrens on Barrow Island. Emu 101: 73-78. pdf

Tarvin K A and Woolfenden G E. 1999. Blue Jay (Cyanocitta cristata). In The Birds of North America, No. 469 (Poole A and Gill F, eds.). The Birds of North America, Inc., Philadelphia, PA. 32 pages. (See Smith, Tarvin, and Woolfenden 2013, above, for revised version).

Pruett-Jones S and Tarvin K A. 1998. Monk parakeets in the United States: population growth and regional patterns of distribution. Proceedings of the 18th Vertebrate Pest Conference (Baker R O and Crabb A C, Eds.), pp. 55-58. pdf

Tarvin K A, Garvin M C, *Jawor J M, and *Dayer K A. 1998. A field evaluation of techniques used to estimate density of Blue Jays. Journal of Field Ornithology 69: 209-222. pdf

Tarvin K A and Woolfenden G E. 1997. Patterns of dominance and aggressive behavior in Blue Jays at a feeder. Condor 99: 434-444. pdf

Tarvin K A and Smith K G. 1995. Microhabitat factors influencing predation and success of suburban Blue Jay Cyanocitta cristata nests. Journal of Avian Biology 26: 296-304. pdf

Tarvin K A. 1994. Long-eared Owl observed in Highlands County, Florida. Florida Field Naturalist 22: 110-111. pdf

Petit K E and Tarvin K A. 1990. First record of a Prothonotary Warbler (Protonotaria citrea) from the Galapagos Islands, Ecuador. American Birds 44: 1094. Sorry, no pdf…