Entomology: A Discipline's Metamorphosis

TUCSON—Karen Saucier’s first glimpse of her new workplace—the insect molecular genetics laboratory at South Carolina’s Clemson University—came as a shocking disappointment. “I almost cried,” recalls Saucier, who had just left a high-powered postdoctoral fellowship at a human genetics laboratory at the University of Miami and was eager to apply those techniques to insects. What confronted her upon arriving at Clemson last year was a huge storage room filled with desks and dusty insect cages. It took her a month to empty the room, and even longer to get some stratup money—$40,OOO from Clemson’s biotechnology program. As the only person on the 27-person entomology faculty who was trained in molecular biology, she was referred to as the biotechnology freak. “They didn’t think I had much purpose,” she recalls. Slowly, she is proving them wrong. For years, Clemson taxonomist John Morse has struggled to develop the means to identify caddisfly larvae, but still he can distinguish only about one in three species. But Saucier’s training led her to take quite a different perspective. Why not just grind up the larvae and identify them by the genetic makeup, of the adults, she suggested. Delighted with Saucier’s recommendation, Morse plans to work with her to develop this approach. The positive response has given Saucier hope that someday she’ll convince the rest of her colleagues that molecular biologists have something important to offer entomologists. Saucier is not alone in her quest to modernize this very conservatiye science. Last month, at the International Symposium on Molecular Insect Science held here, about 300 kindred spirits swapped tales of frustration and success along with scientific information. One hundred more were turned away for lack of space. This new breed is made up of biologists who just happen to have chosen insects as their organism to study. The researchers call themselves insect scientists to distinguish themselves from entomologists, who traditionally devote most of their time to seeking ways to control insect pests. “In the U.S., we tend to think of entomologists as ‘bug hunters’ and ‘nozzleheads,’ “says Elizabeth Bernays, head of entomology at the University of Arizona. “It’s particularly important [for us] to develop a new image.” Insect scientists ply their trade within biochemistry, physiology, neurobiology, and other departments. Their success comes in part from their ability to transcend traditional disciplinary boundaries. At the meeting, about 70 hailed from entomology. Another 60 came from biology departments, 36 from biochemistry, and about 90 from other academic disciplines. About 50 work in industry or government laboratories. “Continued interaction between people like us is essential to keep this field growing,” says James Truman, professor of zoology, at the University of Washington, Seattle. Gerald Selzer, head of special projects within the biological, behavioral, and social sciences directorate at the National Science Foundation agrees. “You have chemists standing up and talking about cloning genes, which I think is pretty remarkable," he says. The Tucson meeting grew out of a 1986 symposium on molecular entomology. That meeting, in Steamboat Springs, Cob., drew 150 people to discuss trends in molecular methods for crop protection and molecular entomology. Organizers expected a similar number for this year’s symposium, with insects as its sole focus, and were overwhelmed by the response. “The time was right, the place was right, and the venue was right,” says Judith Willis, professor of entomology at the University of Illinois at Urbana-Champaign. “Many new experiments are being done.” Sophisticated Science Those experiments are becoming increasingly sophisticated, says John Law, who helped to organize both conferences. Three years ago, says Law, there was only a crude incorporation of DNA techniques into the science. “Now it’s cutting-edge molecular biology.” For example, one researcher has succeeded in transferring DNA by using honeybee sperm; it may be a way to develop honeybees that are more resistant to insecticides. Another scientist awed conference participants by demonstrating the existence of the receptor for ecdysone, a gene-activating hormone important for molting, and two genes it activates. “Its existence had’ been postulated,” says Willis, “but now we have the gene.” Participants see this work, by Stanford graduate student Michael Koelle, as a landmark contribution to the field. Molecular biologists are attracted to insect science, according to Law, in part because so little is known about insect biology. With perhaps millions of species not yet identified, the field is much more open to discovery than, say, yeast genetics, the details of which have been explored for several decades. Scientists also hope that it may be possible to harness insects for the production of new products in biotechnology. Other researchers are abandoning vertebrates in their experiments because of pressure from animal-rights groups (see story on page 5) or because they feel overwhelmed by new regulations. Programs such as the new National Institutes of Health initiative to develop nonvertebrate models for human diseases help to fuel this trend. “Everyone is concerned about the use of animals,” says NSF’s Selzer. “And obviously there are tremendous advantages [in using insects] in terms of cost.” But molecular biologists and other insect scientists are bucking a long tradition that has kept basic biologists and entomologists in separate laboratories. The schism developed more than a century ago, in the 1 850s, when taxonomists and basic biologists formed what they called the “Brethren of the Net” to separate themselves from applied entomologists. Although the two groups were reunited 100 years later into the Entomological Society of America (ESA), “you don’t hear a lot of basic biology at the ESA meeting,” says Henry Hagedom, director of the Center for Insect Science at the University of Arizona, which sponsored this meeting (see accompanying story). Entomology has used classical solutions to the problem of controlling pests through the use of insecticides, predators or parasites, and disruptions in the insect’s habitat. These strategies are all part of integrated pest management, says Hagedom. “What’s missing,” he notes, “are the tools that basic biologists cah bring to bear on this question.” Some entomologists have felt threatened by these new techniques. There is also a language problem: Entomology is a world of kill rates and percent survival, while insect scientists talk about DNA probes and gel electrophoresis. Another source of friction are the differing philosophies. “They have a whole set of assumptions that are not shared [by insect scientists],” says Hagedorn. Entomologists differ from insect scientists not only in what they study and how they study it, but also in what they consider important to study and understand. Once entomologists explain their problems more clearly, Hagedom says, they will realize “that basic biologists can help them.” The system of government support for entomology has hindered the use of insect science in the war against insect pests. Until about five years ago, the U.S. Department of Agriculture (USDA) funneled all its funds through its land grant colleges. That meant researchers in biology departments couldn’t obtain support even if they were interested in applied problems. The USDA Competitive Grants Program, a mere $50 million of the $900 million total USDA research budget, ended that exclusion, but only for work related to three pest species. In addition, the size of the average grant—$50,000 a year for two years—is really too small to be the major support of molecular work, says Law. Clemson’s Saucier has tried to get NSF to support the use of advanced molecular techniques to understand an insect that annually causes millions of dollars of damage. But she says that reviewers don’t know what to make of her application. Entomologists who reviewed the proposal called her techniques “wishful thinking,” she says, and genetics reviewers weren’t interested because “it was only a bug.” The new generation of insect scientists is determined to change these old attitudes. “The people from entomology can’t be so parochial,” says Truman. “They need to reach out to where the advances are occurring.” And they say that history is on their side. For example, 20 years ago, Cornell’s Agricultural Experiment Station in Geneva, N.Y. hired a chemist, Wendell Roelofs, to help its entomologists. He has since made so much progress understanding insect pheromones and applying that knowledge to integrated pest management that, despite his total lack of training in biology, Roelofs has won almost every award available to an entomologist. Now he, too, is turning to molecular techniques. Roelofs lobbied successfully for the station to hire a molecular biologist instead of an economic entomologist when a slot opened up a few years ago. “We feel it’s more important to take new technology to a practical level,” he says. Curriculum Changes The entomology department at his parent land-grant college, Cornell University, has not been as forward in its thinking, however. And it is not alone in its reluctance to embrace change. In general,’ fewer and fewer undergraduates are choosing entomology as a major, and graduate students interested in insects often study insects outside entomology departments to be better trained for industry and academic jobs when they graduate. “If we’re going to stay up with the rest of the world,” says Roelofs, “we have to have people who are moving into areas such as molecular biology.” Change is particularly hard for large, well-established departments, where faculty compete for students and— grants, and interdisciplinary projects often suffer at the hands of empire builders within departments. But some places are opening up. They are hiring faculty with a molecular bend, and they are revising their courses. The University of Illinois, for example, has substituted an insect genetics course for its required insect morphology course. The University of Arizona is planning even more radical shifts. Instead of offering an undergraduate degree in entomology, the department plans to offer a degree in plant protection to those interested in a more traditional approach and one in insect science that stresses biochemistry and molecular biology as well as ecology and behavior. A shift toward basic biology is inevitable, say some insect scientists. “Places that don’t change will probably have to close down their departments,” predicts Arizona’s Bernays.

Entomology: A Discipline's Metamorphosis

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