James D. M. Tolliver

The human-induced biodiversity loss is without a doubt one of the greatest challenges in our time. Diversity within species only persists under certain environmental and evolutionary conditions. I am interested in how diversity persists over time evolutionarily and through conservation actions. In the past I have researched the factors that influence detection, occupancy, and abundance of populations for applied conservation of species. Now, I have shifted my focus to another aspect of biodiversity persistence, how different genetic types are maintained within a population over an evolutionary time scale.

My main study system for these evolutionary studies is the ruff (Philomachus pugnax). This species represents a unique system for examining persistence of genetically distinct morphs. Both male and female ruffs fall into one of three distinct morphs called Independents, Satellites, and Faeders. Satellites and Faeders arose as the result of a chromosomal inversion. Remarkably, although recent findings suggest that this inversion represents a genetic handicap, the three morphs exist across ruff populations at relatively stable frequencies. Molecular dating indicates that they have been present in the ruff species for hundreds of thousands of years. Independents are the most frequent type in males and females whereas Faeders are very rare with less 1% of adults belonging to this morph. My central PhD project will examine the frequencies of the different morphs in the wild at different life stages with two sex demographic modeling. These population-matrix models are intended to provide parameter estimates that may elucidate how all three morphs persist within ruff populations.