Research Interests
I am interested in understanding the extent to which natural populations can adapt to anthropogenic stressors on short time scales. There is growing evidence that human activities may be precipitating rapid phenotypic change in nature; however, much uncertainty remains regarding the rate, limits, and ubiquity of such responses, as well as the mechanisms underlying them (i.e., heritable change vs. environmentally-induced plasticity). Addressing these questions can provide insight into micro-evolutionary processes, and moreover, is critical for predicting species’ persistence in the face of continuing anthropogenic disturbance. My PhD research explores patterns of contemporary phenotypic change in Rastrineobola argentea (mukene), a fish of growing commercial importance in the Lake Victoria basin, in East Africa. I am examining changes in morphological and life history traits in mukene in response to two major anthropogenic stressors: the introduction of a novel predator, the Nile perch, in the late 1950s, and the development of an intensive commercial fishery in the 1990s. These two stressors have undoubtedly shifted the adaptive landscape for R. argentea considerably, both by imposing high size-selective mortality and by dramatically reducing the diversity and abundance of competitors.

Education 2009 Ph.D. Candidate, McGill University, Department of Biology Supervisor:  Dr. Lauren Chapman 2007 B.Sc. (Hon), McGill University, Department of Biology     Past Research 2007 Morphological Variation in Three-Spine Stickleback   Analyzed morphological variation in wild and lab-reared stickleback using geometric morphometrics (Honour’s Project, McGill University) Supervisor: Dr. Andrew Hendry 2006 Mating Behaviour and Sexual Selection in Ladybird Beetles   Conducted laboratory experiments to study influence of condition on mating behaviour in the two-spot ladybird beetle (NSERC USRA, University of Toronto) Supervisors: Jen Perry and Dr. Locke Rowe 2006 Estimating Above-Ground Biomass for Native Trees in Panama   Sampled biomass and leaf cover from an experimental tropical hardwood plantation in Sardinilla, Panama to develop species-specific allometric regressions to estimate above-ground biomass for six native tree species. Internship, Smithsonian Tropical Research Institute (STRI) Supervisor: Dr. Catherine Potvin

A mukene fishermen lands his catch at dawn on Lake Nabugabo, Uganda. Over 100,000 tonnes are harvested in Uganda every year.

Publications

Sharpe, D. and Hendry, A.P. 2009. Life history change in commercially exploited fish stocks: an analysis of trends across studies. Evolutionary Applications. 2:260-275. [PDF] Perry, J.C., Sharpe, D., Rowe, L.  2009. Condition-dependent female remating resistance generates sexual selection on male size in a ladybird beetle. Animal Behaviour, 77 (3): 743-748. [PDF] Sharpe, D., Räsänen, K., Berner, D., and Hendry, A.P. 2008. Genetic and environmental contributions to the morphology of lake and stream stickleback: implications for gene flow and reproductive isolation.  Evolutionary Ecology Research, 10 (6): 849-866. [PDF] Media coverage National Geographic News Watch: "The Little Fish That Could"

Examining the stomach contents of the introduced Nile perch, a major predator of mukene. Lake Nabugabo, Uganda.

Sampling mukene on Lake Kayanja, Uganda.	Women sun-dry mukene in Kikondo village, on the Northern shores of Lake Victoria, Uganda.  Lake Victoria is the largest inland fishery in Africa (supporting over 200,000 fishing families in three countries), and mukene is now the most important non-export stock in the lake.