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Todd Freeberg

Todd FreebergTodd Freeberg
Ph.D., Indiana University (1997)

Phone: (865) 974-3975
Web site:

Key words: Communication, bird song, social learning, development, courtship behavior, birds, comparative psychology, ethology, behavioral ecology.

Research Interests

I am interested in vocal communication, and have focused my studies thus far on bird species, using a combination of field and laboratory approaches. My research seeks to understand the development, function, and evolution of vocal signals and signaling.

Research statement

Research in the lab aims to understand relationships between social organization and systems of vocal communication. We seek to take comparative approaches in the research, to try to uncover ecological and social influences on systems of vocal signals. Recent and ongoing projects in the lab include:

  • testing the roles of group size and complexity of social interactions on vocal signaling
  • experimental tests of the role of traffic noise on avian vocal signaling and social behavior
  • testing the functions of variation in the 'chick-a-dee' call of chickadees and titmice
  • uncovering the relationships among social context, 'personality', and communication in chickadees and titmice
  • 2009 - University of Tennessee Department of Psychology Faculty Appreciation Award: Graduate Teaching and Research.
  • 2011 - Fulbright Award to teach in Latvia, Spring 2012
    J. William Fulbright Foreign Scholarship Board.  $25,000.
    UT – Knoxville approved leave for spring 2012


  • Jung, H., Sherrod, A., LeBreux, Price, J. & Freeberg, T. M. (2020). Traffic noise and responses to a simulated approaching avian predator in mixed-species flocks of chickadees, titmice, and nuthatches. To appear in Ethology.


  • Coppinger, B. A., Davis, J., & Freeberg, T. M. (2019). Flockmate familiarity affects note composition of chick-a-dee calls. Acta Ethologica, 22, 73-77.
  • Freeberg, T. M., Gentry, K. E., Sieving, K. E., & Lucas, J. R. (2019). On understanding the nature and evolution of social cognition: a need for the study of communication. Animal Behaviour, 155, 279-286.
  • Gentry, K. E., Roche, D. P., Mugel, S. G., Lancaster, N. D., Sieving, K. E., Freeberg, T. M., & Lucas, J. R. (2019). Flocking propensity by satellites, but not core members of mixed-species flocks, increases when individuals experience energetic deficits in a poor-quality foraging habitat. PLoS ONE , 14, e0209680. DOI: 10.1371/journal/pone.0209680.


  • Bush, J. M., Jung, H., Connell, J. P., & Freeberg, T. M. (2018). Duty now for the future: a call for public outreach by animal behaviour researchers. Animal Behaviour, 139, 161-169.
  • Coppinger, B. A., Sanchez de-Launay, A., & Freeberg, T. M. (2018). Carolina chickadee (Poecile carolinensis) calling behavior in response to threats and in flight: flockmate familiarity matters. Journal of Comparative Psychology, 132,16-23.
  • Lucas, J. R., Gentry, K. E., Sieving, K. E., & Freeberg, T. M. (2018). Communication as a fundamental part of Machiavellian Intelligence. Journal of Comparative Psychology, 132, 442-454.


  • Coppinger, B., Cannistraci, R. A., Karaman, F., Kyle, S. C., Hobson, E. A., Freeberg, T. M., & Hay, J. F. (2017). Studying audience effects in animals: what we can learn from human language research. Animal Behaviour, 124, 161-165.
  • Freeberg, T. M., Eppert, S. K., Sieving, K. E., & Lucas, J. R. (2017). Diversity in mixed species groups improves success in a novel feeder test in a wild songbird community. Scientific Reports, 7:43014 | DOI: 10.1038/srep43014.
  • Jung, H., & Freeberg, T. M. (2017). Variation in chick-a-dee calls of bridled titmice (Baeolophus wollweberi): frequent use of non-combinatorial calls in a combinatorial calling system. Ethology, 123, 835-842.


  • Cantwell, L. R., Johnson III, W. T., Kaschel, R. E., Love, D. J., & Freeberg, T. M. Predator-risk-sensitive foraging behavior of Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor) in response to the head orientation of snake predator models. (2016). Behavioral Ecology & Sociobiology, 70, 533-539.
  • Freeberg, T. M., Book, D. L., & Weiner, R. L. (2016). Foraging and calling behavior of Carolina chickadees (Poecile carolinensis) in response to the head orientation of potential predators. Ethology, 122, 10-19.
  • Johnson III, W. T., & Freeberg, T. M. (2016). Pseudoreplication in use of predator stimuli in experiments on antipredator responses. Animal Behaviour, 119, 161-164.
  • Kershenbaum, A., Blumstein, D. T., Roch, M. A., Akçay, C., Backus, G., Bee, M. A., Bohn, K., Cao, Y., Carter, G., Cäsar, C., Coen, M., DeRuiter, S. L., Doyle, L., Edelman, S., Ferrer-i-Cancho, R., Freeberg, T. M., Garland, E. C., Gustison, M., Harley, H. E., Huetz, C., Hughes, M., Bruno, J. H., Ilany, A., Jin, D. Z., Johnson, M., Ju, C., Karnowski, J., Lohr, B., Manser, M. B., McCowan, B., Mercado III, E., Narins, P. M., Piel, A., Rice, M., Salmi, R., Sasahara, K., Sayigh, L., Shiu, Y., Taylor, C., Vallejo, E. E., Waller, S., & Zamora-Gutierrez, V. (2016). Acoustic sequences in non-human animals: a tutorial review and prospectus. Biological Reviews, 91, 13-52.
  • Kyle, S. C., & Freeberg, T. M. (2016). Do Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor) attend to the head or body orientation of a perched avian predator? Journal of Comparative Psychology, 130, 145-152.


  • Bartmess-LeVasseur, J. N., & Freeberg, T. M. (2015). Isolation increases time to emerge from shells in two Coenobita hermit crab species. Acta Ethologica, 18, 221-225.
  • Book, D. L., & Freeberg, T. M. (2015). Titmouse calling and foraging are affected by head and body orientation of cat predator models and possible experience with real cats. Animal Cognition, 18, 1155-1164.
  • Freeberg, T. M., & Krams, I. (2015). Does social complexity link vocal complexity and cooperation? Journal of Ornithology, 156, S125-S132.
  • Kershenbaum, A., Freeberg, T. M., Gammon, D. E. (2015). Estimating vocal repertoire size is like collecting coupons: a theoretical framework with heterogeneity in signal abundance. Journal of Theoretical Biology, 373, 1-11.
  • Vrublevska, J., Krama, T., Rantala, M. J., Mierauskas, P., Freeberg, T. M., & Krams, I. A. (2015). Personality and density affect nest defence and nest survival in the great tit. Acta Ethologica, 18, 111-120.


  • Krams, I., Krama, T., Moore, F. R., Kivleniece, I., Kuusik, A., Freeberg, T. M., Mänd, R., Rantala, M. J., Daukšte, J., & Mänd, M. (2014). Male mealworm beetles increase resting metabolic rate under terminal investment. Journal of Evolutionary Biology, 27, 541-550.
  • Krams, I., Kivleniece, I., Kuusik, A., Krama, T., Freeberg, T. M., Mänd, R., Sivacova, L., Rantala, M. J., & Mänd, M. (2014). High repeatability of anti-predator responses and resting metabolic rate in a beetle. Journal of Insect Behavior, 27, 57-66.


  • Freeberg, T. M., & Branch, C. L. (2013). Call variation in tufted titmice (Baeolophus bicolor) in a distress context: potential sex differences. Ethology, 119, 680-691.
  • Freeberg, T. M., & Mahurin, E. J. (2013). Variation in note composition of chick-a-dee calls is associated with signaler flight in Carolina chickadees, Poecile carolinensis. To appear in Ethology.
  • Krams, I., Daukšte, J., Kivleniece, I., Kaasik, A., Krama, T., Freeberg, T. M., & Rantala, M. J. (2013). Trade-off between cellular immunity and life span in mealworm beetles Tenebrio molitor. Current Zoology, 59, 340-346.
  • Krams, I., Kivleniece, I., Kuusik, A., Krama, T., Freeberg, T. M., Mänd, R., Vrublevska, J., Rantala, M. J., & Mänd, M. (2013). Predation selects for low resting metabolic rate and consistent individual differences in anti-predator behavior in a beetle. Acta Ethologica, 16, 163-172.
  • Krams, I., Kivleniece, I., Kuusik, A., Krama, T., Mänd, R., Rantala, M. J., Znotiņa, S., Freeberg, T. M., & Mänd, M. (2013). Predation promotes survival of beetles with lower resting metabolic rates. Entomologia Experimentalis et Applicata, 148, 94-103.


  • Branch, C. L., & Freeberg, T. M. (2012). Distress calls in tufted titmice (Baeolophus bicolor): are conspecifics or predators the target? Behavioral Ecology, 23, 854-862.
  • Burghardt, G. M., Bartmess-LeVasseur, J. M., Browning, S. A., Morrison, K. E., Stec, C. L., Zachau, C. E., & Freeberg, T. M. (2012). Perspectives – Minimizing observer bias in behavioral studies: a review and recommendations. Ethology, 118, 511-517.
  • Freeberg, T. M. (2012). Geographic variation in note composition and use of chick-a-dee calls of Carolina Chickadees (Poecile carolinensis). Ethology, 118, 555-565.
  • Freeberg, T. M., Dunbar, R. I. M., & Ord, T. J. (2012). Social complexity as a proximate and ultimate factor in communicative complexity. Philosophical Transactions of the Royal Society of London, B, 367, 1785-1801.
  • Freeberg, T. M., & Lucas, J. R. (2012). Information theoretical approaches to chick-a-dee calls of Carolina chickadees (Poecile carolinensis). Journal of Comparative Psychology, 126, 68-81.
  • Freeberg, T. M., Lucas, J. R., & Krams, I. (2012). The complex call of the Carolina chickadee: what can the chick-a-dee call teach us about communication and language? American Scientist, 100, 398-407. 
  • Freeberg, T. M., & Moore, T. M. (2012). Research ethics education challenges in a psychology department. Teaching Ethics, 12, 107-111.
  • Freeberg, T. M., Ord, T. J., & Dunbar, R. I. M. (2012). The social network and communicative complexity: preface to theme issue. Philosophical Transactions of the Royal Society of London, B, 367, 1782-1784.
  • Krama, T., Vrublevska, J., Freeberg, T. M., Kullberg, C., Rantala, M.J., & Krams, I. (2012). You mob my owl, I'll mob yours: birds play tit-for-tat game. Scientific Reports, 2, 800; DOI:10.1038/srep00800.
  • Krams, I., Krama, T., Freeberg, T. M., Kullberg, C., & Lucas, J. R. (2012). Linking social complexity and vocal complexity: a parid perspective. Philosophical Transactions of the Royal Society of London, B, 367, 1879-1891.
  • Zachau, C. E., & Freeberg, T. M. (2012). Chick-a-dee call variation in the context of 'flying' avian predator stimuli: a field study of Carolina chickadees (Poecile carolinensis). Behavioral Ecology & Sociobiology, 66, 683-690.


  • Bartmess-LeVasseur, J., Branch, C. L., Browning, S. A., Owens, J. L., & Freeberg, T. M. (2010). Predator stimuli and calling behavior of Carolina chickadees (Poecile carolinensis), tufted titmice (Baeolophus bicolor), and white-breasted nuthatches (Sitta carolinensis). Behavioral Ecology & Sociobiology, 64, 1187-1198.
  • Bērziņš, A., Krama, T., Krams, I., Freeberg, T. M., Kivleniece, I., Kullberg, C., & Rantala, M. J. (2010). Mobbing as a tradeoff between safety and reproduction in a songbird. Behavioral Ecology, 21, 1054-1060.
  • Freeberg, T. M. (2010) Cultural inheritance of signals. In M. D. Breed and J. Moore (Eds.), Encyclopedia of Animal Behavior, Volume 1, (pp. 435-439). Oxford: Academic Press.
  • Lucas, J. R., & Freeberg T. M. (2010) Communication: an overview. In M. D. Breed and J. Moore (Eds.), Encyclopedia of Animal Behavior, Volume 1, (pp. 337-339). Oxford: Academic Press.
  • 2009
  • Freeberg, T. M., & Lucas, J. R. (2009). Pseudoreplication is (still) a problem. Journal of Comparative Psychology, 123, 450-451.
  • Mahurin, E. J., & Freeberg, T. M. (2009). Chick-a-dee call variation in Carolina chickadees and recruiting flockmates to food. Behavioral Ecology, 20, 111-116.


  • Freeberg, T. M.  (2008). Complexity in the chick-a-dee call of Carolina chickadees (Poecile carolinensis): associations of context and signaler behavior to call structure. Auk, 125, 896-907.
  • Freeberg, T. M. & Harvey, E. M. (2008). Group size and social interactions are associated with calling behavior in Carolina chickadees, Poecile carolinensis. Journal of Comparative Psychology, 122, 312-318.
  • Freeberg, T. M., King, A. P., & West, M. J. (2008). Behavioral compatibility and reproductive outcomes in two distant populations of captive brown-headed cowbirds (Molothrus ater). Journal of Comparative Psychology, 122, 437-440.
  • Schwartz, J. J., & Freeberg, T. M. (2008). Acoustic interaction in animal groups: signaling in noisy and social contexts. Journal of Comparative Psychology, 122, 231-234.


  • Freeberg, T. M., Baker, M. C., Bloomfield, L. L., Charrier, I., Gammon, D. E., Hailman, J. P., Lee, T. T.-Y., Lucas, J. R., Mennill, D. J., & Sturdy, C. B. (2007). Complexities in vocal communication. In K. Otter (Ed.), Ecology and Behavior of Chickadees and Titmice: An Integrated Approach, (pp. 235-240), Oxford: Oxford University Press.
  • Harvey, E. M. & Freeberg, T. M. (2007). Behavioral consistency in a changed social context in Carolina chickadees. Journal of General Psychology, 134, 229-245.
  • Lucas, J. R. & Freeberg, T. M. (2007). "Information" and the chick-a-dee call: communicating with a complex vocal system. In K. Otter (Ed.), Ecology and Behavior of Chickadees and Titmice: An Integrated Approach, (pp. 199-213). Oxford: Oxford University Press.
  • Lucas, J. R., Freeberg, T. M., Long, G. R., & Krishnan, A. (2007). Seasonal variation in avian auditory evoked responses: a comparative analysis of Carolina chickadees, tufted titmice, and white-breasted nuthatches. Journal of Comparative Physiology, A, 193, 201-215.
  • Owens, J. L. & Freeberg, T. M. (2007). Variation in chick-a-dee calls of tufted titmice, Baeolophus bicolor: note type and individual distinctiveness. Journal of the Acoustical Society of America, 122, 1216-1226.


  • Freeberg, T. M. (2006). Social complexity can drive vocal complexity: group size influences vocal information in Carolina chickadees. Psychological Science, 17, 557-561.
  • Freeberg, T. M. & White, D. J. (2006). Social traditions and the maintenance and loss of geographic variation in mating patterns of brown-headed cowbirds. International Journal of Comparative Psychology, 19, 206-222.
  • Lucas, J. R, Freeberg, T. M., Egbert, J., & Schwabl, H. (2006). Fecal corticosterone, body mass, and caching rates of Carolina chickadees (Poecile carolinensis) from disturbed and undisturbed sites. Hormones and Behavior, 49, 634-643.

(student co-authors listed in bold)

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