Scientist Honored for Pioneering Research on Ocean Optics
For over six decades, Yale scientist Talbot Waterman has been bringing insights into how aquatic animals use polarized light — i.e., the directional orientation of light that indicates the sun’s position in the sky — to navigate underwater.
Waterman, 94, the professor emeritus of molecular, cellular and developmental biology, was recently honored for his contributions to the field of ocean optics by the Oceanography Society, which presented him with its Nils Gunnar Jerlov Award at the 19th Ocean Optics Conference in Barga, Italy. The award is named in honor of Nils Gunnar Jerlov, an early leader in the area of ocean optics research.
“Waterman’s pioneering contributions to the body of knowledge regarding underwater polarization and aquatic animals forms the foundation of our understanding of these phenomena,” said Steven G. Ackleson of the U.S. Office of Naval Research, during the award ceremony. “His work continues to inspire new generations of researchers.”
Upon receiving the award, Waterman said, “All of us encounter substantial ups and downs in our personal and professional lives. My receipt of this 2008 Jerlov Award is really a peak for me both as a welcome personal honor and as professional recognition.
“This euphoric state,” he added, “is lifted even higher by the fact that Nils Gunnar Jerlov and I collaborated oceanographically on three main projects, and we became good friends over the course of more than 30 years beginning in the mid-1950s.”
The inspiration for Waterman’s research came shortly after he arrived at Yale in 1946, when he attended a departmental seminar given by Karl von Frisch, who had discovered by studying the honeybee dance language that they relied on the polarized light in the sky to navigate between their hives and nectar-rich flower patches.
Hearing this, Waterman wondered, “Is underwater polarization of light an important element in the visual behavior of aquatic animals?” He decided to investigate that question.
There was little precedent for this work in the 1950s, so he had to draw on his earlier lab and shipboard research, as well as his wartime experiences with radar navigation. Waterman packed up a simple but novel polarimeter [a device that measures polarized waves] and took off for the Bermuda Biological Station - a location familiar from his days as a graduate student - to look for light polarization patterns underwater.
“In the first underwater observations via snorkel and scuba, the hand-held ‘Waterman’ interference polarimeter was used to detect the probable patterns,” he said. “Excitingly, the data showed that substantial partial linear polarization occurred everywhere in shallow sunlit water.”
To check whether this phenomenon extended into deep water, he took photographs with a camera lowered from a ship off Barbados.
“Those photos proved that considerable sun-influenced polarization was still present at a depth of 200 meters,” said Waterman. “Hence, these light patterns are not weak, only superficial or fixed in time. Accordingly, we undertook a more sophisticated investigation of underwater polarization with quantitative polarimeters and in collaboration with underwater optics experts.”
For more than 40 years, Waterman’s funded research at Yale also included many aspects of the physiological and behavioral relevance of underwater optics to biology. Working with his students and postdoctoral collaborators, he conducted experiments and did related work that tackled questions ranging from the visual behavior and light ecology of crustaceans and fishes, to the mechanisms of polarization sensitivity, to the compass-like direction-finding and progress measurements of basic navigation. To understand how sensitive sea creatures were to underwater polarized light, he did research involving light and electron microscopy of the eyes and retinas, as well as the molecular biology of the visual pigments that absorb the light and start signals toward the brain via the optic nerve.
Waterman continues to tackle the challenge — bringing together scientists with expertise in relevant fields to solve the next layer of questions.
“At 94, I am still trying to bridge the gap between experts in marine animal navigation and those in optics, because they typically don’t know much about each other’s fields” said Waterman. “It is wonderful to have the perspective of 60 years at work on an important but still unsolved problem of global science. Not many people have that opportunity.”
— By Janet Rettig Emanuel