Current Research

Neuro-endocrine and behavioral mechanisms of female dominance and reproductive skew in wild meerkats
  • Lab members involved: Kristin Dimac, Alexandra Stonehill, Nick Grebe
Integrating endocrine, morphological, behavioral, and chemical analyses, this project examines the factors that influence the acquisition and expression of female dominance in meerkats. Specifically, we are testing if, via prenatal androgen exposure, the ʻmasculinizationʼ of females predicts future social rank and reproductive success. By blocking the effect of androgens during pregnancy, we are exploring (a) the activational role for androgens on adult females, (b) the organizational role for androgens on developing offspring. 

Eco-immunology and the impact of androgens in wild meerkats
  • Lab members involved: Kendra Smyth (dissertation project)
Focusing on a population of wild meerkats in South Africa's Kalahari desert, this project investigates the influence of prenatal and activational androgens on immunity and health.  

Determining the influence of diet quality on gut bacteria and health in captive and wild lemurs
  • Lab members involved: Lydia Greene (dissertation project)
The bacteria that inhabit mammalian guts are hugely important for regulating host health. Yet, we know relatively little about the factors that shape gut microbiomes. In this project, I am using both captive and wild lemurs to explore the impact of diet quality on gut bacterial consortia.

Relating variation in olfactory signals to scent-gland bacteria in ring-tailed lemurs
  • Lab members involved: Lydia Greene 
Olfactory signaling is a critical communicatory modality in lemurs, but the mechanism(s) by which volatile compounds are synthesized is not well understood. This project examines whether the symbiotic bacteria inhabiting lemur scent glands may contribute, via fermentation, to the host's chemical profile.  

Ontogeny of olfactory signatures and microbial communities in meerkats ​
  • Lab members involved: Rachel Harris, Lydia Greene
This project uses an experimental approach to describe the development of functional scent glands in wild meerkats, with a focus on (1) the development of ‘adult’ olfactory signatures as offspring become mature, (2) concurrent bacterial colonization of scent glands, and (3) the influence of prenatal androgen exposure on these processes. 
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Olfactory signals of injury and health in ring-tailed lemurs
  • Lab members involved: Rachel Harris
Mammalian olfactory signals convey information about both stable (sex, species, genetic quality) and transient (reproductive state, infection) condition to conspecifics. Variations in odor cues associated with individual health suggest such cues are costly to produce, but there is limited evidence outside of laboratory systems. I am using a social, aggressive species, the ring-tailed lemur, as a model with which to examine how odor cues become altered during periods of naturally-occurring injury, and whether such changes are salient to conspecifics.
 
Bacteria as mediators of olfactory communication in ring-tailed lemurs
  • Lab members involved: Rachel Harris
Ring-tailed lemurs rely on a complex array of volatile compounds for communication, many of which may be produced by fermentative bacteria inhabiting the host’s scent glands. We manipulated lemur scent gland bacterial communities to determine the microbial contribution to olfactory signatures, and describe patterns of both chemical and microbial recolonization or ‘recovery’.​

Examining antimicrobial resistance and gut microbiome structure in relation to primate health
  • Lab members involved: Sally Bornbusch
I am broadly interested in how microbiome structure influences the host. Particularly, how do changes in gut microbial communities, such as those brought on by age or antibiotics, affect host health. In addition, I am studying how exposure to antibiotics affects antibiotic-resistance in microbial communities. I am investigating these questions in multiple lemur species.

On-going & completed research

  • Olfactory communication in ring-tailed lemurs & Coquerel's sifakas relative to social and reproductive factors
  • Comparative studies on the composition of chemical signals in primates
  • The genetic diversity of several immune-function genes in captive and wild ring-tailed lemurs
  • Relating urinary volatile compounds to hormone profiles in binturongs
  • Investigating the expression of female dominance, masculinization, and aggression in spotted hyenas
  • Comparative behavior and neuro-endrocrinology of the genus Eulemur

Representative Publications:

Media Coverage
2017
  • Grebe, N.M. & Drea, C.M. (2017) Human Sexuality. Encyclopedia of Evolutionary Psychological Science. 00:1-14.
  • Grogan, K.E., Sauther, M.L., Cuozzo, F.P., Drea, C.M. (2017) Genetic wealth, population health: Major histocompatibility complex variation in captive and wild ring-tailed lemurs (Lemur catta). Ecology and Evolution. 00:1–12. 
  • Leclaire, S., Jacob, S., Greene, L.K., Dubay, G.R. & Drea, C.M. (2017) Social odours covary with bacterial community in the anal secretions of wild meerkats. Scientific Reports 7.
2016
  • Davies, C.S., Smyth, K.N., Greene, L.K., Walsh, D.A., Mitchell, J., Clutton-Brock, T.H. & Drea, C.M. (2016) Exceptional endocrine profiles characterize the meerkat: sex, status, and reproductive patterns. Scientific Reports 6.
  • delBarco-Trillo, J., Greene, L.K., Goncalves, I.B., Fenkes, M., Wisse, J.H.,  Drewe, J.A.,  Manser, M.B., Clutton-Brock, T., Drea, C.M. (2016). Beyond aggression: Androgen-receptor blockade modulates social interaction in wild meerkats. Hormones and Behavior. 78: 95-106.
  • Greene, L.K., Grogan, K.E., Smyth, K.N., Adams, C.A., Klager, S.A. & Drea, C.M. (2016) Mix it and fix it: functions of composite olfactory signals in ring-tailed lemurs. Open Science 3.
  • Greene, L. K., Wallen, T. W., Moresco, A., Goodwin, T. E. & Drea, C. M. (2016). Reproductive endocrine patterns and volatile urinary compounds of Arctictis binturong: discovering why bearcats smell like popcorn. The Science of Nature, 103(5-6), 1-11.
  • Grogan, K.E., McGinnis, G.J. and Drea, C.M. (2016) Next- generation genotyping of hypervariable loci in large numbers of a non-model species: technical and theoretical implications. BMC Genomics. 17: 204
  • Smyth, K.N., Greene, L.K., Clutton-Brock, T., & Drea, C.M. (2016) Androgens predict parasitism in female meerkats: a new perspective on a classic trade-off. Biology Letters, 12, 20160660.
  • Smyth, K.N. and Drea, C.M. (2016). Patterns of parasitism in the cooperatively breeding meerkat: a cost of dominance for females. Behavioral Ecology. 27(1), 148–157.
2015
  • Crawford, J. and Drea. C.M. (2015). Baby on board: olfactory cues indicate pregnancy and fetal sex in a non-human primate. Biology Letters, 11(2): 20140831.   
  • Drea, C.M. (2015). D'scent of man: A comparative survey of primate chemosignaling in relation to sex. Hormones and Behavior, 68: 117-133.
  • Petty, J.M. & Drea, C.M. (2015). Female rule in lemurs is ancestral and hormonally mediated. Scientific Reports, 5: 9631.    
2014
  • Cunha, G.R., Risbridger, G., Wang, H., Place, N.J., Wilson, J., Grumbach, M., Siiteri, P., Cunha, T.J., Conley, A.J., Barcellos, D., Agarwal, S., Bhargava, A., Drea, C.M., Hammond, G., Weldele, M., Baskin, L.S., Glickman, S. Development of the external genitalia: Perspectives from the spotted hyena. Differentiation, 87 (1): 4-22.
  • delBarco-Trillo, J. & Drea, C.M. (2014). Socioecological and phylogenetic patterns in the chemical signals of strepsirrhine primates. Animal Behaviour, 97: 249-253.
  • Greene, L.K. & Drea, C.M. (2014). Love is in the air: sociality and pair bondedness influence sifaka reproductive signaling. Animal Behaviour 88: 147-156.
  • Kulahci, I.G., Drea, C.M., Rubenstein, D.I. & Ghazanfar, A.A. (2014). Individual recognition through auditory-olfactory matching in lemurs. Proceedings of the Royal Society of London, B, 281(1784): 20140071. http://dx.doi.org/10.1098/rspb.2014.0071.
  • Leclaire, S., Nielsen, J.F., & Drea, C.M. (2014). Bacterial communities in meerkat anal scent secretions vary with host sex, age, and group membership. Behavioral Ecology, 25 (4): 996-1004.
2013
  • Charpentier, M.J.E. & Drea, C.M. (2013). Victims of infanticide and conspecific bite wounding in a female-dominant primate: a long-term study. PLoS ONE, 8(12): e82830.
  • Charpentier, M.J.E., Mboumba, S., Ditsoga, C., & Drea, C.M. (2013) Nasopalatine Ducts and Flehman Behavior in the Mandrill: Reevaluating Olfactory Communication in Old World Primates. American Journal of Primatology, 75 (7): 703-714.
  • delBarco-Trillo, J., Harelimana, I.H., Goodwin, T.E., & Drea, C.M. (2013) Chemical Differences Between Voided and Bladder Urine in the Aye-Aye (Daubentonia madagascariensis): Implications for Olfactory Communication Studies. American Journal of Primatology, 75(7): 695-702.
  • Drea, C.M., Boulet, M., delBarco-Trillo, J., Greene, L.K., Sacha, C.R., Goodwin, T.E., & Dubay, G.R. (2013) The “Secret” in Secretions: Methodological Considerations in Deciphering Primate Olfactory Communication.  American Journal of Primatology, 75(7): 621-642.
2012
  • delBarco-Trillo, J., Sacha, C., Dubay, G., & Drea, C.M. (2012). Eulemur, me lemur: the evolution of scent-signal complexity in a primate clade. Philosophical Transactions of the Royal Society B: Biological Sciences, 367: 1909-1922.
  • Hammond, G.L., Miguel-Queralt, S., Yalcinkaya, T.M., Underhill, C., Place, N.J., Glickman, S.E., Drea, C.M., Wagner, A. & Siiteri, P.K. (2012). Phylogenetic comparisons implicate sex hormone-binding globulin in “masculinization” of the female spotted hyena (Crocuta crocuta). Endocrinology, 153(3): 1435-1443. 
  • MacLean, E., Matthews, L.J., Hare, B., Nunn, C.L., Anderson, R.C., Aureli, F., Brannon, E.M., Call, J., Drea, C.M., Emery, N.J., Haun, D.B.M., Herrmann, E., Jacobs, L.F., Platt, M.L., Rosati§, A.G., Sandel*, A., Schroepfer, K.K., Seed, A.M., Tan, J., van Schaik, C.P., & Wobber, V. (2012). How does cognition evolve? Phylogenetic comparative psychology. Animal Cognition, 15: 223-238. 
  • Rushmore, J, Leonhardt, S.D., & Drea, C.M. (2012) Sight or scent: lemur sensory reliance in detecting food quality varies with feeding ecology. PLoS ONE 7(8): e41558.
2011
  • Crawford, J., Boulet, M., & Drea, C.M. (2011). Smelling wrong: Hormonal contraception in lemurs alters critical female odour cues. Proceedings of the Royal Society of London, B, 278(1702): 122-130.
  • delBarco-Trillo, J., Burkert, B.A., Goodwin, T.E., Drea, C.M. (2011). Night and day: the comparative study of strepsirrhine primates reveals socioecological and phylogenetic patterns in olfactory signals. Journal of Evolutionary Biology, 24: 82-98.
  • Drea, C.M. (2011). Endocrine correlates of pregnancy in the ring-tailed lemur (Lemur catta): Implications for the masculinization of daughters. Hormones & Behavior, 59(4): 417-427.
  • Place, N.J., Coscia, E.M., Dahl, N.J., Drea, C.M., Holekamp, K.E., Roser, J., Sisk, C.L., Weldele, M.L., & Glickman, S.E. (2011). The anti-androgen combination, flutamide plus finasteride, paradoxically suppressed LH and androgen concentrations in pregnant spotted hyenas, but not in males. General & Comparative Endocrinology, 170 (3): 455-459.
2010
  • Boulet, M., Crawford, J., Charpentier, M.J.E., & Drea, C.M. (2010). Honest olfactory ornamentation in a female-dominant primate. Journal of Evolutionary Biology, 23(7): 1558-1563.
  • Charpentier, M.J.E., Crawford, J., Boulet, M., & Drea, C.M. (2010). Message ‘scent’: lemurs detect the genetic relatedness and quality of conspecifics via olfactory cues. Animal Behaviour, 80: 101-108.
  • Starling, A.P., Charpentier, M.J.E., Fitzpatrick, C., Scordato, E.S. & Drea, C.M. (2010). Seasonality, sociality, and reproduction: Long-term stressors of ring-tailed lemurs (Lemur catta). Hormones & Behavior, 57: 76-85.
2009
  • Boulet, M., Charpentier, M.J.E., & Drea, C.M. (2009). Decoding an olfactory mechanism of kin recognition and inbreeding avoidance in primates. BMC Evolutionary Biology, 9:281.
  • Drea, C.M. (2009). Endocrine mediators of masculinization in female mammals. Current Directions in Psychological Science, 18(4): 221-226.
  • Drea, C.M. & Carter, A.N. (2009). Cooperative problem solving in a social carnivore. Animal Behaviour, 78: 967-977.
  • Leonhardt, S.D., Tung, J., Camden, J.B., Leal, M. & Drea, C.M. (2009). Seeing red: behavioral evidence of trichromatic color vision in strepsirrhine primates. Behavioral Ecology, 20(1): 1-12.
2008
  • Charpentier, M.J.E., Boulet, M. & Drea, C.M. (2008). Smelling right: The scent of male lemurs advertises genetic quality and relatedness. Molecular Ecology, 17(14): 3225-3233.
  • Charpentier, M.J.E., Williams, C. & Drea, C.M. (2008). Inbreeding depression in ring-tailed lemurs (Lemur catta): Genetic diversity predicts parasitism, immunocompetence, and survivorship. Conservation Genetics, 9(6): 1605-1615.
  • Drea, C.M. & Scordato, E.S. (2008). Olfactory communication in the ringtailed lemur (Lemur catta): form and function of multimodal signals. In: J.L. Hurst, R.J. Beynon, S.C. Roberts, & T. Wyatt (eds.), Chemical Signals in Vertebrates 11, pp. 91-102. Springer Press, New York.
  • Drea, C.M. & Weil, A. (2008). External genital morphology of the ringtailed lemur (Lemur catta): females are naturally ‘masculinized.’ Journal of Morphology 269(4): 451-463.
2007
  • Drea, C.M. (2007). Sex and seasonal differences in aggression and steroid secretion in Lemur catta: are socially dominant females hormonally ‘masculinized’? Hormones & Behavior 51(4): 555-567.
  •  Scordato, E.S. & Drea, C.M. (2007). Scents and sensibility: information content of olfactory signals in the ringtailed lemur (Lemur catta). Animal Behaviour 73(2): 301-314.
  • Scordato, E.S., Dubay, G. & Drea, C.M. (2007). Chemical composition of scent marks in the ringtailed lemur (Lemur catta): glandular differences, seasonal variation, and individual signatures. Chemical Senses 32: 493-504.
2006
  • Drea, C.M. (2006). Studying primate learning in group contexts: tests of social foraging, response to novelty, and cooperative problem solving. Methods 38(3): 162-177.
  • Glickman, S.E., Cunha, J.R., Drea, C.M., Conley, A.J. & Place, N.J. (2006). Mammalian sexual differentiation: lessons from the spotted hyena. Trends in Endocrinology & Metabolism 17: 349-356.
2005-1991

  • Drea, C.M. (2005). Bateman revisited: the reproductive tactics of female primates. Integrative & Comparative Biology 45(5): 915-923.
  • Drea, C.M. (2004). Mammalian olfactory communication. In: M. Bekoff (Ed.), Encyclopedia of Animal Behavior, Vol.1 (pp. 369-374). Westport, CT: Greenwood Press.
  • Drea, C.M. & Frank, L.G. (2003). The social complexity of spotted hyenas, in Animal Social Complexity: Intelligence, Culture, and Individualized Societies, edited by F.B.M de Waal & P.L. Tyack (2003), pp. 121-148, Cambridge, MA: Harvard University Press.
  • Drea, C.M., Place, N.J., Weldele, M.L., Coscia, E.M., Licht, P. & Glickman, S.E. (2002). Exposure to naturally circulating androgens during foetal life incurs direct reproductive costs in female spotted hyenas, but is prerequisite for male mating. Proceedings of the Royal Society of London B 269: 1981-1987.
  • Drea, C.M., Vignieri, S.N., Cunningham, S.B., & Glickman, S.E. (2002). Responses to olfactory stimuli in spotted hyenas (Crocuta crocuta): I. Investigation of environmental odors and the function of rolling. Journal of Comparative Psychology 116(4): 331-341.
  • Drea, C.M., Vignieri, S.N., Kim, H.S., Weldele, M.L., & Glickman, S.E. (2002) Responses to olfactory stimuli in spotted hyenas (Crocuta crocuta): II. Discrimination of conspecific scent. Journal of Comparative Psychology 116(4): 342-349.
  • Drea, C.M., Coscia, E.M., & Glickman, S.E. (1999). Hyenas, Encyclopedia of Reproduction, edited by E. Knobil, J. Neill, & P. Licht, vol. 2, pp. 718-725, San Diego: Academic Press.
  • Drea, C.M. & Wallen, K (1999) Low status monkeys "play dumb" when learning in mixed social groups, Proceedings of the National Academy of Sciences, USA 96(22): 12965-12969.
  • Drea, C.M. (1998) Social context affects how rhesus monkeys explore their environment, American Journal of Primatology 44: 205-214.
  • Drea, C.M. (1998) Status, age, and sex effects on performance of discrimination tasks in group-tested rhesus monkeys (Macaca mulatta), Journal of Comparative Psychology 112(2): 170-182.
  • Drea, C.M., Weldele, M.L., Forger, N.G., Coscia, E.M., Frank, L.G., Licht, P., & Glickman, S.E. (1998) Androgens and masculinization of genitalia in the spotted hyaena (Crocuta crocuta). 2. Effects of prenatal anti-androgens, Journal of Reproduction & Fertility 113: 117-127.
  • Glickman, S.E., Coscia, E.M., Frank, L.G., Licht, P., Weldele, M.L., & Drea, C.M. (1998) Androgens and masculinization of genitalia in the spotted hyaena (Crocuta crocuta). 3. Effects of juvenile gonadectomy. Journal of Reproduction & Fertility, 113(1): 129-135.
  • Glickman, S.E., Zabel, C.J., Yoerg, S.I., Weldele, M., Drea, C.M., & Frank, L.G. (1997) Social facilitation, affiliation and dominance in the social life of spotted hyenas, Annals of the New York Academy of Sciences, Vol. 807: The Integrative Neurobiology of Affiliation, edited by C.S. Carter, I. I. Lederhendler, & B. Kirkpatrick, pp. 175-184, NY: New York Academy of Sciences.
  • Drea, C.M., Hawk, J.E., & Glickman, S.E. (1996) Aggression decreases as play emerges in infant spotted hyaenas: preparation for joining the clan, Animal Behaviour 51(6): 1323-1336.
  • Drea, C.M., Hawk, J.E., & Glickman, S.E. (1996) The emergence of affiliative behavior in infant spotted hyenas (Crocuta crocuta), Poster presented at the New York Academy of Sciences Conference on the Integrative Neurobiology of Affiliation, Washington, DC.
  • Drea, C.M. & Wallen, K. (1995) Gradual acquisition of visual discrimination tasks in a social group of rhesus monkeys (Macaca mulatta), Animal Learning & Behavior, 23(1): 1-8.
  • Drea, C.M., Wallen, K., Akinbami, A., & Mann, D.R. (1995) Neonatal testosterone and handedness in yearling rhesus monkeys (Macaca mulatta), Physiology & Behavior, 58(6): 1257-1262.
  • Fagot, J., Drea, C.M., & Wallen, K. (1991) Asymmetrical hand use in rhesus monkeys (Macaca mulatta) in tactually and visually regulated tasks, Journal of Comparative Psychology, 105(3): 260-268.
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 Lab news! Archive

December 2016
  • Kendra and Alex present on offspring health mediation by maternal traits in wild meerkats at the 4th Annual Ecology Symposium in Durham, NC. 
November 2016
  • Congratulations to Lydia for successfully completing her prelim and officially becoming a PhD candidate.
  • Rachel presents on injury and health alterations to scent signals in ring-tailed lemurs (Lemur catta) at the Regional Meeting of the Society for Integrative & Comparative Biology in Durham, NC.
October 2016
  • Welcome Nicholas Grebe, the Drea Lab's newest postdoc.
  • New paper out of the Drea Lab! Androgens predict parasitism in female meerkats: a new perspective on a classic trade-off. See publications for more details! 
  • New paper out of the Drea Lab! Patterns of parasitism in the cooperatively breeding meerkat: a cost of dominance for females. See publications for more details! ​
August 2016
  • Kendra and Charli present on organizational and activational effects of androgens in meerkats at the International Society for Behavioral Ecology's meeting in Exeter, UK.
May 2016
  • Congratulations to Professor Christine Drea on her induction into the Bass Society of Fellows for Excellence in Teaching and Research, as the Earl D. McLean, Jr. Professor of Evolutionary Anthropology!
​ April 2016
  • Congratulations to Sammi and Alex for successfully defending their Undergraduate thesis!
  • Congratulations to Kendra for getting a STERN fellowship :)
  • New paper out of the Drea Lab!  Mix it and fix it: functions of composite olfactory signals in ring-tailed lemurs. See publications for more details! 
  • New paper out of the Drea Lab!  Reproductive endocrine patterns and volatile urinary compounds of Arctictis binturong: discovering why bearcats smell like popcorn. See publications for more details!
February 2016
  • Welcome Rachel Harris who joined the lab as a postdoc.
  • Congratulations to Kendra for getting a NSF doctoral dissertation improvement grant (DDIG)!!!
January 2016
  • Congratulations to Kendra for winning best DEDE student oral presentation at SICB!
November 2015
  • New paper out of the Drea Lab!  Beyond aggression: Androgen-receptor blockade modulates social interaction in wild meerkats. See publications for more details!
August 2015
  • Welcome Sally Bornbusch who joined the lab as a EvAnth graduate student.
  • New paper out of the Drea Lab! Patterns of parasitism in the cooperatively breeding meerkat: a cost of dominance for females. See publications for more details!
July 2015
  • Joe Petty successfully defended his PhD!
May 2015
  • New paper out of the Drea Lab :) Female rule in lemurs is ancestral and hormonally mediated. See publications for more details!
March 2015
  • Series premiere of "Killer IQ: Lion vs. Hyena." Part 1, 'Predator Games' airs Mar 4 and part 2, 'Predator Challenge,' airs Mar 11 on the Smithsonian Channel. 
February 2015
  • New paper out of the Drea Lab! Baby on board: olfactory cues indicate pregnancy and fetal sex in a non-human primate. See publications for more details!
January 2015
  • Welcome Samantha Epstein, our newest undergraduate researcher!
September 2014
  • Katie successfully defended her Ph.D. AND started a post-doc at Emory University!
  • Kendra returned to the Kalahari Meerkat Project for 6 months of fieldwork!
  • Welcome Ed Kabay, our newest research assistant!
  • Welcome Hannah Derrick, our newest undergraduate researcher!
August 2014
  • Lydia joined the lab as a UPE graduate student! 

























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