Research

Our lab conducts research in integrative evolutionary biology by studying organismal biology (behavior and physiology) to better understand how vertebrate animals, birds in particular, adapt to changing environments and form new species.

We are currently studying animal migration.  Migration has always intrigued humans— how do billions of birds know how to move thousands of miles each year and return the following spring to breed?  How do they know when and where to go?  And especially, will they be able to ‘keep up’ with environmental change? 

The answer is to be found at many levels, but the one that interests us most is how birds process environmental cues, such as day length and temperature, in order to time annual recurring events.  Will the mechanisms they use serve them well in a changed environment?

Our study system is a songbird, the dark-eyed junco, which is an abundant sparrow-like bird that breeds throughout North America from California to Alaska to Newfoundland and down the Appalachians in the east. Populations that breed in different locations look quite different from one another, different enough to look like separate species and are classified as sub-species.  But when employing a biological species concept, they all belong to one species because they are capable of interbreeding. Populations of this bird also differ in whether and when they migrate: some are sedentary and some migrate thousands of miles.

Recent advances in migration research have made it possible to answer questions that were previously not possible.  Miniature electronic tags enable tracking individuals throughout the year.  Mass spectrometry allows us to determine where a feather was grown months earlier and thus where a bird was likely to have been at that time.  New molecular techniques permit us to compare the genetic nature of individuals and populations – how do they differ gene by gene, and even more importantly how do they differ in terms of which genes are expressed at one time of year or another. It’s an exciting time to be studying migration and evolution.

One response to recent environmental change has been for migratory species to cease migrating, perhaps because surviving the winter is less challenging than it was in the past. An open question is whether the change in behavior reflects a genetic response to natural selection or whether it reflects the capacity for birds to be flexible in whether and when they migrate, depending on current conditions, independently of genetic change.  The answer matters because the environment is changing rapidly and if timing is flexible, it becomes more likely that animals will be able to track changes and avoid extinction.

People currently in the lab are studying behavioral ecology, disease ecology, movement ecology, and seasonality. In juncos, they are assessing the impact of artificial light at night on parasitic infection, migratory timing, and endocrine measures of stress and reproduction. Another is studying connectivity and reproductive readiness in American Robins in Indiana and Alaska as well as species distribution modeling for the junco. We are also quantifying window strikes on campus.