Paul Feeny, a pioneer in the field of chemical ecology, has received a prestigious career award for "groundbreaking, integrative contributions to the understanding of insect-plant interactions" from an international society that he helped found 30 years ago.

Feeny, professor emeritus in the Department of Ecology and Evolutionary Biology, was awarded the International Society of Chemical Ecology's (ISCE) 2011 Silver Medal July 28 at the society's annual meeting in Vancouver, British Columbia, Canada.

The award recognizes "career achievement by an outstanding scientist working in the field of chemical ecology."

Feeny received his B.A. (1960) and M.A. (1961) in chemistry, another B.A. (1963, zoology) and a Ph.D. (1966), all from Oxford University in the U.K., before joining Cornell in 1967 in entomology. Feeny, whose expertise covers chemical ecology, insect-plant interactions, plant defense mechanisms and evolution, became an emeritus professor in 2010.

"It's gratifying to realize that I've helped in the development of this exciting new subject," said Feeny.

In 1970, Feeny published a groundbreaking paper based on his thesis work that explained why the foliage of oak trees is heavily attacked by insect herbivores in the spring but not later in the season. The paper, which has been cited more than 1,000 times, showed that young oak leaves quickly become tough and protein-poor with tannins, which can inhibit digestion of proteins. But very young oak leaves lack these defenses, making them vulnerable to caterpillars that appear at just the right time in the spring.

Feeny's research has also provided experimental support for the theory of co-evolution: As insects and pathogens develop resistance to plant defenses, plants evolve to counter their strategies, which in turn prompts the pests to develop new attack methods, thereby creating a kind of "co-evolutionary arms race," a term he helped popularize. Feeny and his students showed that compounds characteristic of one plant family, while innocuous to insects attacking that family, can be toxic to insect pests of other plant families.

A major contribution to the field was Feeny's 1976 "apparency theory," which extended plant defense discussions beyond physiological cost/benefit tradeoffs.

The kind of chemical defense a plant has against attacking herbivores and pathogens, suggested Feeny, depends on how susceptible the plant is to being discovered. "Easy-to-find" plants, like oaks, employ "quantitative" defenses that generally interfere with a pest's ability to get nutrients from leaves, including such physical defenses as thorns, spines and tough, nutrient-poor leaves, and such compounds as resins, silica and tannins that interfere with feeding or digestion.

Less apparent plants, like crucifers (including cabbages) and other herbaceous species, employ "qualitative" defenses -- these are small amounts of unique toxins that are effective against wandering pests, but are likely to be overcome eventually.

While many ecologists study the interplay of plant defenses vs. herbivore attacks, "there has been relatively little work on how insects recognize plants chemically and how plants may modify their chemistry for escape," said Feeny. He and colleagues in Japan have published dozens of papers on the plant chemicals used as egg-laying stimulants by swallowtail butterflies. The patterns of stimulant evolution in this model family are now clear and have already explained some puzzling host shifts by swallowtails to atypical host-plant families.

Feeny coordinated the first chemical ecology course at Cornell (likely the first anywhere) in 1970; he co-chaired the first Gordon conference on chemical interactions between plants and herbivores in 1980, which led to the foundation of the ISCE in 1983; and he received a Guggenheim fellowship in 1983-84. He played a major role in the development of the Max-Planck Institute for Chemical Ecology in Jena, Germany, and served as the first Chair of its Scientific Advisory Board (1998 to 2002).