By Gerry Boyle ’78
Biologist Dave Angelini and his collaborator, Will Simmons ’17J, have published findings of their three-year study of the effect of pesticides on bumblebees and hope the results will have the scientific community looking for new solutions to the problem.
Starting with a bee population kept in tents on campus, Angelini and Simmons set out to see whether pesticides used on agricultural fields were compromising the disease-fighting ability of the key pollinators.
“We got data and we got the answer to the question,” Angelini said of the study published March 21 in the journal Scientific Reports, which is affiliated with the prestigious journal Nature. “The surprising thing scientifically was that we had an effect of pesticide exposure—but in the opposite direction of what we had predicted.”
Simmons was a sophomore when he brought the question to Angelini, assistant professor of biology, who studies genetic function in other insect species. The topic was timely as scientists were trying to figure out why neonicotinoids, a type of pesticide commonly used in agriculture, were linked to declining bee populations.
The pair devised the experiment, which dosed captive bumblebees of the species Bombus impatiens with the levels of pesticide they would be exposed to in an agricultural setting and then studying the effect on certain genes that act as a bee’s equivalent to antibodies in humans. They found that those genes, linked to the production of antimicrobial peptides, were, in fact, affected.
“We assumed exposing them to the pesticide would cause expression of these antimicrobial peptides, the immune-related genes, to go down,” Simmons said. “In the end, we saw the exact opposite response. They went up.” Why?
Angelini and Simmons have their theories, which they lay out in the journal paper. Perhaps the increase in defenses affects the bee’s microbiome, the collection of healthy bacteria and viruses it carries in its stomach. Or maybe it’s a generalized stress response. Said Simmons, “That’s research.”
He should know. Two months after receiving his Colby diploma, he’s embarked on a very different project—a job at the National Institutes of Health in Bethesda, Md., doing genetic research connected to mutations that worsen sickle cell disease. “Honestly,” Simmons said, “I couldn’t have been more prepared for what I’m doing now.”
He’s working at the NIH for geneticist David Bodine ’76, Sc.D.’13, who he first met two years ago at the Colby Liberal Arts Symposium. “I didn’t know who he was at the time,” he said. “He came up and grilled me on my poster.”
It’s a new direction for Simmons—and for Angelini as well. Introduced to bumblebee science by his student researcher, Angelini is continuing work with the “charismatic animal.” When he visited Allen Island, Colby’s research island off the coast of Maine, Angelini noticed that the island was home to a robust colony of the Northern Amber Bumblebee, which is rare on the mainland.
That piqued his scientific curiosity, so this summer he will lead a group of incoming students enrolled in the Colby Achievement Program in the Sciences to Allen Island. They’ll survey the bumblebee population and see if, indeed, bees that are rare on the mainland are thriving offshore.
Angelini is moving in the direction of ecology; Simmons is moving toward genetics. “It was a good pairing,” he said. “I think both of us ended up going in a direction we wouldn’t have expected.”