Tom Cronin, professor of biological sciences, and his longtime colleague, Justin Marshall, professor at the University of Queensland in Australia, have received the 2020 Rank Prize for Optoelectronics. The prize honors their pioneering discovery of new ways that eyes can perceive color and a rare type of light that has twisted electromagnetic waves, called circular polarization.
Lord Joseph Arthur Rank established the Rank Funds for Nutrition and Optoelectronics in 1972. Each year, the fund committees designate prize winners in each category from an international pool of nominees. Past winners have included Mike Land of the University of Sussex, who is considered by many to be the top expert on comparative vision internationally, and Jeremy Nathans of Johns Hopkins University, who was the first to determine the DNA sequence for the visual pigments in human eyes.
Cronin and Marshall’s award includes an unrestricted £40,000 for each recipient and a trip to London for the award ceremony on January 20, 2020. On receiving the prize jointly, Cronin says, “We’re both very glad that both of us were included. It’s been more than 30 years that we’ve been working side by side.”
Cronin and Marshall’s first joint effort, in 1988, resulted in an article that graced the cover of Nature, generally considered to be the most prestigious scientific journal in the world. With such a strong start to their collaboration, the duo decided to keep a good thing going. Since then, “Justin and I have published almost all of our work jointly. There’s very little that we do that hasn’t involved both labs,” Cronin says.
Marshall sees the collaboration as born out of mutual interests that have only grown over the years. “We see ourselves as a couple of guys interested in nature,” he says, “and the way we study it has made us get to know a fair bit of biology, but also other areas of science, like physics and chemistry, and how it all fits together in a discipline called visual ecology.”
The world’s weirdest eyes
The two researchers focus on the visual system of the mantis shrimp, which is “just extraordinarily strange,” Cronin says. He explains, “Justin and I both work to develop understanding of this very complex, extremely unusual, and very dynamic visual system that’s unlike any other that’s ever been described.”
“Basically,” says Marshall, “we got a prize for describing weirdness beyond our wildest dreams.” For example, mantis shrimps have more color channels than any other animal that humans know of. The colorful critters have at least eight, and possibly as many as 16, channels. In comparison, humans have only three. Some channels allow the shrimps to see ultraviolet light, while the large number of channels in the visual light spectrum may allow them to identify colors more quickly.
On top of that, “Mantis shrimps combine this color vision system with a very complicated polarized light vision,” Cronin says. Light can be polarized linearly—that’s why your camera screen looks black when you’re wearing polarized sunglasses. “There’s another kind of polarization that’s far rarer, and optically complex, but that mantis shrimps can see. It’s called circular polarization,” Cronin explains. In fact, mantis shrimp are the only animals known to be able to see circular polarization.
Some mantis shrimps have circularly polarized markings on their bodies, which has led researchers to hypothesize that mantis shrimps may use their circularly polarized vision to identify other individuals as potential mates or competitors.
Camouflage, cancer, and mantis shrimps?
One might ask what mantis shrimp vision has to do with optoelectronics. The number of scientists doing basic research who are among the Rank Prize winners speaks to the importance of projects that lay the foundation for work on applications, Cronin says. “A common misconception is that if you don’t work in an optoelectronics lab, or if you don’t work with mice and zebrafishes, you’re not going to discover anything important,” he says. “And that’s just not true.”
Cronin and Marshall’s work to understand how mantis shrimps detect polarized light, and specifically circularly polarized light, has a range of applications. A medical technology for guided breast tumor surgery is currently in development, for example.
Cronin adds, “Circularly polarized light can also be used to ‘see’ objects that are otherwise camouflaged, which is why we get funded by the military.” The unusual light can also assist in navigation that doesn’t require GPS satellites.
Marshall agrees about the value of foundational research. “We did not set out to solve these problems,” he says, “but we found solutions along the way.”
A lifetime of achievement
Mantis shrimps have rocketed to public fame in recent years, in part due to research out of Cronin’s lab and his appearances in media such as the podcast RadioLab. “I think public outreach is very important,” says Cronin, who estimates he’s contacted by at least one media outlet per month. “You need people to be interested in the fact that science is exciting, and it’s a frontier.”
The selection committee, guests of the Rank Funds, and family members and guests of the recipients will attend the celebration in London. Cronin’s colleagues plan to travel from institutions across the globe to attend the event, where he’ll give a brief acceptance speech on his and Marshall’s behalf.
“We make a great team and have been lucky over the years to work with others who also share our passion,” shares Marshall.
The prize “recognizes a lifetime of achievement and is an exceptional honor,” Cronin says. “It will be exciting to be there with all my colleagues from 40 years of research.”
Image: Peacock mantis shrimp (Odontodactylus scyllarus) with eggs. Photo by Christian Gloor, used under CC BY 2.0.