My research interests are in evolutionary biology. Field studies and analytical methods from a variety of different disciplines including population genetics, physiology, protein chemistry, and wildlife biology are being used to address questions about the process of adaptation and natural selection, at both the molecular level and in whole organisms. Waterfowl and other waterbird species inhabiting high-altitude regions such as the Andes are of particular interest, as are diving birds.

High altitudes are characterized by extreme differences in ambient pressure and temperature that vary across elevational gradients. Hypoxia in particular is one of the most important factors influencing survival, and biochemical changes in the blood protein hemoglobin (Hb) have been shown to mitigate the effects of chronic exposure to hypoxia in high-altitude adapted populations. Surveys of hemoglobin polymorphism in Andean waterfowl indicate that genotypic variants that are over-represented in high-altitude populations have resulted in increased Hb-O2 affinity and that these changes have occurred over relatively short evolutionary time periods. However, hemoglobin represents only one part of the O2 transport cascade. Mechanistic changes have occured at many other points affecting O2 transport, and the outcomes may not be as simple or uniform as that observed for hemoglobin. Examples include how individuals modulate their Hb-O2 carrying capacity and vary their ventilation rate and cardiovascular response in response to hypoxia. Changes also occur influencing cellular metabolism. The roles of development and phenotypic plasticity and how they may alternatively promote the process of genetic adaptation or shield genotypes from natural selection are also of interest.

Collaborators on these projects have included Jay Storz at the University of Nebraska, Roy Weber at the University of Aarhus, Bill Milsom at the University of British Colombia, Graham Scott at McMaster University, Jeff Peters at Wright State University, and Kevin Winker at the University of Alaska Museum. We also maintain close ties with investigators at the Alaska Science Center and several South American museum, Thomas Valqui at the Centro de Ornitologia y Biodiversidad (CORBIDI) and the Museo Argentino de Ciencias Naturales (MACN).

Prospective students or postdocs with strong interests in population genetics, high-altitude physiology, Andean biogeography, or any aspect of waterfowl ecology and management are encouraged to contact us.

I have joint appointments on all three campuses of the University of Miami and can advise PhD students in the Department of Biology, Rosenstiel School of Marine and Atmospheric Science, and Hussman Institute for Human Genomics.

If you are interested in conducting research in my lab send me an email with some details about your background and research interests. My email is spelled like my name: kevin.g.mccracken at gmail dot com

You can follow recent activitites in my lab on our Google+ website.

Grant support: NSF 0444748, 0746365, 0814322, 0949439/0949931