Research program

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This research statement intentionally starts very broad since in my experience many undergraduate students (and some graduate students) have a partial understanding of what science is and its methods.

There are many definitions of science, but it is often defined as an endeavor that seeks to discover how nature works. Science generates knowledge through the scientific process: 1) observation and description of natural phenomena, 2) formulation of hypotheses, which are proposed explanations for the observed phenomena, 3) deduction of predictions from the hypotheses, 4) experiments to test the predictions derived from the hypotheses. I also consider communication to be part of the scientific process. Therefore, I strongly believe in the need to publish research in peer-reviewed journals.

I embrace the entire scientific approach with conviction. I am therefore interested in observation to discover patterns, but I am more interested in developing and testing hypotheses to explain these patterns. The two patterns I have tried to explain to date are: 1) what dictates spatial variation in animal density and 2) why some animals are polymorphic. I have primarily used reptiles as study organisms. Since reptiles are, proportionally, the most at-risk group of vertebrates in Canada, I have also done conservation research.

Spatial variation of density

Within species, abundance varies markedly across space. Abundance at large spatial scales is primarily driven by abiotic factors. Abundance at small spatial scales is primarily a function of individual reproduction and survival, which, in turn, are partially a function of habitat selection. Terrestrial ectothermic vertebrates present a unique opportunity to bridge habitat selection and fitness since their performance varies as a function of body temperature, which is regulated primarily by habitat selection. Much of the literature on habitat selection assumes that animals are limited by their ability to harvest resources. But what if animals are limited by their ability to assimilate resources? Most vertebrates are ectotherms, and in ectotherms the total amount of available energy may be more strongly affected by thermal constraints that dictate resource assimilation than by resource acquisition. My working hypothesis is that the abundance of ectotherms is dictated primarily by their ability to assimilate resources, rather than by their ability to acquire resources.

Polymorphism

Polymorphism is very common in plants and animals. Some polymorphisms are easily explained (e.g., ontogenetic polymorphism, geographic polymorphism), but polymorphisms within a population are more intriguing since we would expect a population under selection to converge toward an optimal phenotype. Therefore, the evolutionary persistence of multiple coexisting phenotypes has attracted a lot of attention. Several potential mechanisms that could explain this coexistence have been found, the most common being frequency-dependent selection. I studied a specific case of polymorphism, sexual dimorphism, where the phenotypic differences are between males and females. I found that sexual selection, selection for fertility, and natural selection can explain sexual dimorphism. I am also interested in intrapopulation color polymorphism and tested several hypotheses for its intriguing evolutionary persistence.

Reptile conservation

I conduct applied conservation projects on imperiled reptiles (e.g., describing habitat use and movement patterns), but I am more interested in more fundamental conservation questions, such as the effect of demographic synchrony and anthropogenic mortality on population persistence. Much of my conservation work is inspired by my work on the consequences of habitat selection for fitness, so there is a real connection between my basic and applied research.