RESEARCH PROJECTS:
I am presently working on multiple projects in both temperate and tropical systems. The basic question underlying my research is how do organisms adapt to changing environmental conditions and what factors facilitate and constrain adaptation? I have two major systems that I work with:
- Alaskan threespine stickleback, Gasterosteus aculeatus
- Freshwater fishes of western Ecuador
The first major component of my research involves Alaskan threespine stickleback. Threespine stickleback are rapidly becoming one of the most important systems in evolutionary biology. My primary research on stickleback involves two topics:
1. I study how oceanic stickleback adapt to freshwater conditions. My research takes advantage of a lake (Loberg Lake) that was poisoned (1982) and later recolonized by ocean-run stickleback (sometime between 1983 and 1989). Our lab has sampled the population since 1990. In 1990, the stickleback in the lake looked like ocean fish but they have been adapting to conditions in fresh water and over time have come to look more and more like typical resident freshwater populations. Today it is quite difficult to distinguish them from other resident freshwater populations. I am author on two papers focusing on the Loberg Lake population:
-Aguirre, W.E., P. Doherty, and M.A. Bell. 2004. Genetics of lateral plate and gill raker phenotypes in a rapidly evolving population of threespine stickleback. Behaviour 141:1465-1483. PDF
-Bell, M.A., W.E. Aguirre, and N. Buck. 2004. Twelve years of contemporary armor evolution in a threespine stickleback population. Evolution 58:814-824. PDF
And we have two more in the works, one updating the time series for armor/feeding related traits and looking at genetic diveristy, and another looking at body shape evolution.
2. Once ocean stickleback colonize freshwater environments, how do different factors, like natural selection and gene flow, interact to determine the patterns of phenotypic and genetic variation that we observe? I am taking advantage of a small, ecologically diverse drainage in the Mat-Su Valley of Alaska close to Wasilla, the upper Fish Creek drainage. A study on phenotypic differentiation in response to habitat type has recently been accepted in the Biological Journal of the Linnean Society and should come out towards the end of the year:
-Aguirre, W.E. In Press. Microgeographic diversification of threespine stickleback: body shape-habitat correlations in a small, ecologically diverse Alaskan drainage. Biological Journal of the Linnean Society.
I am now finishing up the microsatellite work to publish that component.
If you want to read more about my research on threespine stickleback you can go to the following link:
The Pattern and Process of Evolutionary Diversification: Lessons from a Threespine Stickleback Adaptive Radiation
Or see my publications page for other papers:
Publications
I'm also interested in tropical systems, particularly in northwestern South America. I am presently developing research projects on the evolutionary biology of freshwater fishes in western Ecuador. The fauna was isolated by the rise of the Andes millions of years ago and is quite old and specialized. It is also under severe threat from anthropomorphic pressures. Western Ecuador has been severely impacted by deforestation, over fishing, and pollution from agricultural run off. You can learn more about the fauna and the area by clicking here:
The Freshwater Fishes of Western Ecuador
I am working on several projects in this area.
Other:
These are research topics that I haven't actively worked on in a while. They may be of interest nonetheless.
The Neotropical Sciaenidae
Fish Otoliths, Hearing, and Growth
Skeletal Anomalies of Ecuadorian Marine Mammals
Last Updated: April 6, 2009
