Evolutionary genetics of energetic performance

Montooth Lab







Evolutionary genetics of cold tolerance

Understanding thermal stress is critical to understanding the fitness of an organism in its environment. Organisms experience fluctuations and extremes in temperature during diurnal temperature cycles, across seasons, over geographical ranges, and as a consequence of global climate change. Organisms have evolved a variety of thermal adaptations to meet the challenges imposed by thermal stress.

While a great deal of progress has been made in understanding adaptations to heat stress (e.g. the heat shock response), less is known about the mechanisms of and adaptations to cold stress. Using the fruit fly, Drosophila melanogaster, I am working on understanding how organisms evolve adaptations to low temperatures. There are a wide variety of genetic tools available for this model ectotherm, making the fruit fly an ideal research subject. Because D. melanogaster is a cosmopolitan species that recently expanded its range from Africa to most of the globe, we will be able to take what we learn about adaptations to cold stress in the laboratory and test the ecological and evolutionary relevance of our results in wild populations distributed across thermal clines.

My research focuses on answering:

1) Why is low temperature stressful to an organism? What are the proximate causes for decreased fitness at low temperatures?
2) How do organisms adapt to cold stress? What is the evolutionary genetic basis underlying adaptations to cold?
3) What costs and tradeoffs are associated with adaptations to cold stress? How do these costs and tradeoffs affect an organism's fitness?