Butterflies and Boeing: An electrical engineer’s unusual odyssey
Gary Bernard’s career splits neatly in half, geographically and in engineering applications — 21 years conducting research on insects at Yale University followed by 20 years with Boeing Commercial Airplanes in Auburn. Flight from the micro to mega scale might seem to be the common thread, but Bernard’s research passion explores eyes and vision, not wings.
Bernard began his electrical engineering career by completing his undergraduate (’59) through doctoral degrees (’64) at UW EE researching electromagnetic waves. Following a fellowship at the Massachusetts Institute of Technology, he moved to Yale University to collaborate with a physiologist in using electromagnetic waves to study insect vision. Long before cross-disciplinary became a buzz word, he held joint appointments in Yale’s departments of engineering and applied science and ophthalmology and visual science.
Over the years he has published scientific papers on bees, houseflies, dragonflies, spiders, beetles, butterflies and moths. One series of publications showed that spiders webs reflect ultraviolet wavelengths to attract prey. In the late 1980s Bernard moved back to Seattle for a full-time engineering position with Boeing, where he did more traditional EE work looking at ways to process signals to detect wear and tear while machining parts.
His insect research equipment moved with him to the Northwest and found a home in UW EE, where he co-advised graduate students as an affiliate professor. He also helped establish the UW Center for Auditory and Acoustic Research, a multi-university partnership focused on acoustic monitoring. “He just loved working with the students and with junior faculty,” said Les Atlas, a professor of electrical engineering and collaborator of Bernard’s.
In his spare time, Bernard kept up his research investigating the evolution of butterfly vision, working with long-time collaborator Adriana Briscoe, an associate professor of ecology and evolutionary biology at the University of California, Irvine. Atlas remembers that at scientific meetings his colleague could be found wandering off with a butterfly net in hand.
After retiring three years ago from Boeing, Bernard built a research lab in his Federal Way home, and installed his equipment, a high-tech “opthalmologist’s office” for insects, and revved up the third phase of his career. Last year he and Briscoe co-authored a paper in the Proceedings of the National Academy of Sciences that may shine light on how some butterflies seek out prospective mates, the latest of nine joint publications. Heliconius butterflies are famous for having wing colors and patterns that vary with geographic location. As many as a dozen species in one location may look identical to confuse predators. “Ok, they fool the predators, but how do they avoid fooling themselves?” said Bernard. “How do they recognize butterflies of the same species when they look so similar?”
Butterflies, Bernard discovered in the 1960s, have eyeshine, the property that makes a raccoon’s eyes shine in the glare of a car’s headlights. A reaction between incoming light and molecules in the eye causes wavelength shifts in eyeshine color. Bernard measures this carefully for each wavelength to learn exactly which ones the insect can see. In some instances he waits for eight hours in the dark, flashes bright orange light, then measures with dim flashes in different colors every half-hour to see how the eye responds. He takes advantage of visual molecules in the eye that take many hours to recover. A second technique measures pupil contraction in the insects’ compound eyes to verify the results. These painstaking experiments take three days and require middle of the night changes in equipment settings. He then sends the results and the specimens to Briscoe’s lab for the genetic analysis.
According to the new results, Heliconius erato has evolved a second receptor for ultraviolet light so these butterflies are sensitive to small variations in the UV range. What’s more, the UC Irvine researchers found ultraviolet blotches on Heliconius erato’s wings that are not found on other species. The ultraviolet spectrum could be a “private channel” that this species uses to communicate. “Gary does really unusual work. He does physiology on living butterflies. It’s an extremely technically challenging, computationally challenging kind of experimental work,” Briscoe said.
This study’s implications are still speculative, the authors caution, because they have not yet tested whether birds and other predators can also see the ultraviolet wing patterns. But there’s a follow-up paper in the works and other exciting projects in the pipeline. “It’s really cool for me, as an old guy, retired, to be still active and working with a young group that’s pushing the limits,” Bernard said.
More on the butterfly vision research can be found at http://visiongene.bio.uci.edu/.