Travels in Evolutionary Biology

Last summer in Costa Rica, while many tourists were stretching their legs on white-sand beaches, Melissa Bodner ’04 and Kate Baldwin ’05 were in search of eight-legged creatures.

The two research assistants, who accompanied Lewis & Clark Assistant Professor of Biology Greta Binford, rose early to poke sticks into cliff-top crevasses or comb through leaves on the muddy forest floor. They were trying to locate three varieties of spiders: Sicarius and Loxosceles in the arid sands, andDrymusa in the leaf litter of the rainforest. The team’s goal was to bring the spiders stateside to study their feeding habits, venom content, and genetic code for clues to their evolution.

The adventure started in Palo Verde, a large national park in northwest Costa Rica that is considered one of the most ecologically diverse in the country. The park is home to one of three biological research stations owned and operated by the Organization of Tropical Studies, a consortium of 63 universities and research institutions, and is known for its deciduous forest on limestone outcrops. Students searched those sandy cliffs for Sicarius spiders whose bodies, including eight legs, were no bigger than a quarter. “Greta collected a lot more than we did,” Bodner says. “But eventually we got the hang of it.”

Then it was off to a vastly different clime: the wetlands of the southeast Carribean coast, full of swamps, lagoons, flooded forests, and coastal reefs. Working in high heat and humidity just prior to monsoon season, the trio stayed in a national wildlife refuge as guests of the country’s Fundación Neotrópico. During their spider hunts (“We were out in the mud at 6 a.m. every morning,” says Baldwin), they collected the first adult male specimen of two species of Drymusa and one species ofLoxosceles. All of the original males will be deposited in the Smithsonian Institution in Washington, D.C.

Other than airfare, which students paid themselves, much of the trip was financed by the start-up funds Lewis & Clark College provides to new faculty. A similar opportunity awaits two students on Binford’s next South American spider forage: a trip to Argentina in January 2005. Binford recently received a $47,000 grant from the M.J. Murdock Charitable Trust to study patterns of diversity in spider venom, and part of this award will be used to fund the trip.

For students, the trips help connect them to their academic interests in evolutionary biology. In Costa Rica, Bodner and Baldwin saw a vast diversity of species, including poison dart frogs, molting tarantulas, and scorpions. “If we are to preserve that kind of biodiversity,” says Bodner, “we need to understand the evolutionary history of nature and organisms.”