Behavioral Ecology and Evolution lab

Research interests

We examine how ecology, behaviour, and biogeography explain patterns of biodiversity. We are particularly interested in understanding how interactions between related species are affected by resource and interference competition, sexual selection, and genetic relatedness, and how these interactions relate to patterns of phenotypic evolution and species distributions.

Current projects in the lab include:

Patterns of phenotypic variation and their effect on the extent of range overlap and character displacement

AlexBird1Working with collaborators Dr. Thomas Smith and Dr. Daniel Blumstein at UCLA, we found what we believe to be the first compelling demonstration of character displacement in bird song. We found that songs diverge away from each other in frequency where two African Pogoniulus tinkerbird species coexist, supported by parallel divergence in body size and beak shape, and experimental evidence of the importance of song divergence in species recognition. Both acoustic and morphological traits have diverged in concert, presumably to reduce species recognition errors and competition between P.bilineatus (left) and P. subsulphureus.

We are now extending our work on tinkerbirds to include additional geographic regions, plumage and genetic variation, and additional species pairs. We are specifically interested in understanding how variation in phenotype affects the extent of character displacement and range overlap in different species pairs.

Interspecific competition and phenotypic and genetic evolution in Sylvia warblers

AlexBird2

We have embarked on a study of the endemic breeding bird, the Cyprus Warbler, looking at the effects of competition with its congener, the Sardinian Warbler, which has recently invaded the island and is expanding its range. The focus is on understanding interspecific interactions, particularly competition during the breeding season for territories, mates, and nest sites, and how this affects reproductive success of Cyprus Warbler between populations where Sardinian Warbler is present or absent. Comparative work with Sylvia warblers elsewhere in the Mediterranean may shed some light on how other related species maintain coexistence with rivals, through behaviorally plasticity or ecologically divergence.
In relation to this study, we are also investigating the expansion of Sardinian warbler in Cyprus and how a founder effect may cause rapid phenotypic and/or genetic evolution. We are specifically interested in patterns of phenotypic variation, and in particular the appearance of melanistic forms (above) in the breeding population. How do these melanistic individuals interact with typical morph birds, how do they interact with other Sylvia species, and how might these interactions impact the maintenance of the polymorphism in the population? We are also interested in identifying the genetic basis of melanism in these birds.

Individual recognition, localization, territory dynamics, and interactions between Neotropical rainforest birds

In collaboration with Dr. Charles Taylor and Dr. Martin Cody at UCLA, we have been developing a wireless acoustic array to record, identify and localize birds as they vocalize in a Mexican rainforest. We have so far developed systems that localize birds with high levels of accuracy and we have identified over 30 individual Mexican Antthrush using their songs. We are now investigating how individuals interact both towards individuals of the same species and individuals of other species in response to competition.