Tracy Langkilde

Tracy Langkilde

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Associate Professor of Biology

516 Mueller
University Park, PA 16802
Phone: (814) 867-2251
Lab Address: 508 Mueller
Lab Phone: (814) 867-2252

Graduate Programs

Biology (BIOL)

Ecology (ECLGY)



  1. Ph.D., University of Sydney, Australia, 2005
  2. B.S., James Cook University, Australia, 1999

Postdoc Training

  1. Gaylord Donnelley Environmental Fellow, Yale University, 2005 - 2007

Honors and Awards

  1. George Mercer Award, Ecological Society of America, 2011

Research Interests

My research is broadly focused on understanding the processes that structure communities and permit the coexistence of the component species. I am particularly interested in how the nature of interactions between species can shift over time in response to changes in the environment and corresponding selection pressures. The introduction of invasive species is one such perturbation that is becoming increasingly common. My current research examines how invasive fire ants impact the behavior, morphology, and physiology of native lizards across multiple time scales, and the consequences of evolutionary response of native species to these novel selective pressures. This research has both basic and applied relevance, allowing me to address important ecological questions about the evolutionary processes affecting the composition and dynamics of natural communities, while also providing valuable information on the long-term impact of invasive species. My work is mostly field based, and incorporates aspects of population, community, behavioral, and evolutionary ecology. I employ experimental and comparative approaches and molecular techniques to test key hypotheses with two main foci: 1) the evolution of survival strategies and 2) the ecological and evolutionary consequences of stress.

Selected Publications

Trompeter, W. P. and T. Langkilde. 2011. Invader danger: lizards faced with novel predators exhibit an altered behavioral response to stress. Hormones and Behavior 60: 152-158.

Langkilde, T. and N. A. Freidenfelds. 2010. Consequences of envenomation: Red imported fire ants have delayed effects on survival but not growth of native fence lizards. Wildlife Research 37: 566-573.

Langkilde, T. 2010. Repeated exposure and handling effects on the escape response of fence lizards to encounters with invasive fire ants. Animal Behaviour 79: 291-298.

Boronow K. E. and Langkilde T. 2010. Sublethal effects of invasive fire ant venom on a native lizard. Journal of Experimental Zoology Part A 313A: 17-23.

Langkilde, T. 2009. Holding ground in the face of invasion: native fence lizards (Sceloporus undulatus) do not alter their habitat use in response to introduced fire ants (Solenopsis invicta). Canadian Journal of Zoology 87: 626-634.

Langkilde, T. 2009. Invasive fire ants alter behavior and morphology of native lizards. Ecology 90: 208-217.