Prof. Eric J. Olson (Heller) discovered the world's first vegetarian spider, Bagheera kiplingi, while working with a research team from Earthwatch in Costa Rica. Olson's article on his discovery of the vegetarian spider in June 2001 was published Oct. 13.There are around 40,000 different species of spiders, and all were believed to be meat-eaters until the discovery of the vegetarian spider, according to the Boston Globe. Olson wrote in an e-mail to the Justice that the spider belongs to Salticidae, the largest spider family in the world.

"It is rare in the career of a field biologist to see something truly extraordinary, that changes long-held perceptions about the ways organisms can make their living. I feel very fortunate to have played a part in expanding our understanding of natural history in this way," Olson wrote.

Olson wrote that spiders belonging to Salticidae do not build webs to catch their prey but instead stalk and pounce on their prey. "They can jump very fast, but not really very far (couple of inches maybe)," he wrote.

Bagheera kiplingi is "light tan with dark brown blocthes [sic] on its abdomen (for the female) but the male adult includes some dark green and in some light looks somewhat metallic," Olson wrote.

The research that Olson was conducting in Costa Rica had the Earthwatch volunteers observing ants living on the acacia tree. While the volunteers were conducting the research, they noticed a spider on the tree and brought the information to Olson.

According the Earthwatch Web site, the organization "is a diverse community of scientists, educators, students, businesspeople, and resolute explorers who work together to get the fullest benefit from scientific expeditions."

However, a few days later another volunteer saw the spider on the tree. Olson went to the tree and saw the spider being chased by the ants. According to the Boston Globe, Olson observed the spider grab the tree food and run off.

In an e-mail to the Justice, Prof. Dan Perlman (BIOL) wrote, "Eric Olson is a superb ecologist and teacher-and also a highly observant natural historian. Although thousands of tropical ecology students and professors have looked at ant-acacias over the decades, it took the keen observational skills of Eric Olson to see what others had missed: a plant-eating spider. He and his colleagues, with this single observation, have changed our views of a major group of organisms."

"This shows how theory can be a wonderful guide when you are doing applied research but one always has to be willing to challenge the legitimacy of your underlying assumptions. As a Dean I am thrilled to have Professor Olson teaching at Heller," wrote Lisa Lynch, dean of the Heller School for Social Policy and Management, in an e-mail to the Justice.

Regarding his future work, Olson wrote that he will continue teaching at Brandeis and organizing an invasive plant task force that cleans up harmful plants in Newton's parks and along the Charles River.

-- Anya Bergman contributed reporting