COLUMBIA — When David Marshall and his wife, Kathy Hill, get vacation time from their research, they don’t sit on the beach and relax.
“We don’t go on vacations in the sense of doing something else," Marshall said. "We’re the strange kind of people that spend our vacation going off and collecting bugs.”
Marshall and Hill are researchers in the Department of Ecology and Evolutionary Biology at the University of Connecticut. Both have an extreme interest in cicadas. They traveled to Columbia to attend the 2011 Invertebrate Sound and Vibration international meeting June 4-7.,and Marshall gave a presentation about periodical cicadas.
“I know a few other couples — you could call them cicada couples — who happen to share the same strong interest in a particular organism or approach in biology,” Marshall said. “We consider ourselves to be very lucky because the large majority of other people we know who are specialists in insects are married to a ‘normal' person, and seeing them have to negotiate the compromises of travel and field research makes us feel extremely lucky.”
Johannes Schul, an MU professor of biological sciences who coordinated the Columbia conference, said Marshall and Hill aren't entirely unique. He knows quite a few couples who met each other while doing biological research. In fact, that's how he met his wife, Sarah Bush.
Although Marshall gave the cicada lecture at the conference, Hill has had a strong interest in cicadas for much of her adult life, as well.
“We work on everything together, pretty much," Marshall said. "We have complementary interests and strengths. She remembers the species better and often ends up carrying a certain part of the load.”
The two usually have a few different research projects going on simultaneously, and they often work on grant-funded research that takes them around the world.
“We’ve been fortunate to collect (cicadas) in New Zealand, Argentina, China, the Philippines, South Africa and even Fiji,” Marshall said.
Although Marshall has always found insects interesting, his interest was piqued when he learned about the complex and unusual life cycle of the periodical cicada in graduate school.
“It really was the evolutionary puzzle,” Marshall said.
The periodical cicadas are a complex species with unusually long lives for insects, usually spanning a length of a prime number such as 13 or 17. Marshall wanted to learn more about how the species developed.
“I enjoy acoustic insects that have interesting sounds to listen to,” Marshall said. “I am interested in how species evolve, (and with cicadas you) can examine populations at the earliest stages of speciation by telling the difference in the song.”
Marshall and Hill met through a colleague while researching cicadas in New Zealand, which is Hill's native country. Hill's interest in cicadas emerged when she was exposed to them as a child in New Zealand.
“Unlike me, she is the kind of person who imprinted on insects, especially cicadas, at a very young age,” Marshall said. “In New Zealand there is a species of green, adorable cicadas that are present in yards and gardens, which is different than here, where they are up in the trees.”
Since Hill moved to the United States, she and Marshall have done their own field collecting and recording. They have even found new species of cicadas.
The couple is putting together an online field guide to North American cicadas with recordings of their individual songs and maps of their distributions around the country.
“We’ve tape-recorded nearly all of the Eastern North American species,” Marshall said. “If you hear a cicada in your backyard, you can most likely identify the sound on this website.”
Marshall and Hill have collected almost 1,000 cicada species over the years, but they intend to add more. Future plans include finding jobs that allow them to teach while they continue to do research.
The conference in Columbia ended Tuesday. Now the couple plans to travel Missouri and make population collections of periodical cicadas across the state.
“It might seem like a long time for them to be out for someone dealing with the sound, but it's only three weeks of intense activity,” Marshall said. “It’s a brief window for research.”
The couple will embark on their loud, cicada-focused adventure on Wednesday. They hope to make some discoveries about the different species of 13-year periodical cicadas along the way.
“We spend all of our time together," Marshall said. "We both jump in the car and are perfectly happy driving around, sleeping by the side of the road, punching information into the GPS and having endless conversation. We’re both perfectly happy."