Eric S. Chivian ’64, one of the authors of “Sustaining Life: How Human Health Depends on Biodiversity,” believes that the answer to treating stomach ulcers may lie with the gastric brooding frog.

“It’s mostly the ugly and the small that are keeping life going,” he said.

Unfortunately for humanity, this species of frog has been extinct for over a decade.

In a book signing Thursday night at the Harvard Coop, Chivian, the founder and director of the Center for Health and the Global Environment at Harvard Medical School stressed the importance of preserving the planet’s biodiversity.

Co-authored by Aaron Bernstein, his book addresses the loss of biodiversity in terms of potential medical research and treatment.

“We have no [environmental] Hiroshima and Nagasaki,” he said, comparing the negative impact of changes in the global environment to that of nuclear weapons.

Chivian, who won the 1985 Nobel Peace Prize for his role in co-founding International Physicians for the Prevention of Nuclear War, said that more than 50 percent of prescribed medicines come from natural sources or are patterned after natural sources. He said that compounds found in cone snails protect brain cells from death when deprived of blood flow, for example, which may be useful for people with Alzheimer’s and Parkinson’s Disease.

Chivian said he believes that benefits for humans in preserving biodiversity might move both the general public and public policy makers. For this reason, he said it was important to write the book in terms the general public could understand. “We [scientists] are not trained in everyday language; we’re trained in technical language. It is a major problem if scientists can’t communicate to the public,” he said in an interview before the lecture. “We made an enormous effort to write in language that the general public can understand.”

During the question and answer session, Chivian said that the issue of protecting biodiversity is bipartisan. He pointed to a U.S. Senate resolution on protecting biodiversity in developing countries introduced by Delaware Senator Joesph Biden, the Democratic vice presidential candidate, speculating that this might be the beginning of a more robust role for the U.S. in shaping international environmental policy.

Chivian said the book was written as reference for scholars, public policies makers, and students and has already been integrated into university curriculums, as a textbook in “Organismic and Evolutionary Biology 10: Foundations of Biological Diversity” at Harvard, an introduction to environmental science class at University of Wisconsin, and in classes at the University of Warwick in England.

Before the lecture, Chivian lauded Harvard’s efforts toward promoting environmental sustainability. He called Harvard’s green initiative “groundbreaking.”

“It’s been exciting that educational institutions see themselves as providing an example not just for students but for the community,” he said.