Science

Biologist Daniel H. Janzen's dream is to create a tropical forest in the northwest of Costa Rica. Janzen is a professor at the University of Pennsylvania. (Interview by Marty Moss-Coane)

Fiction and science writer David Quammen. His column "Natural Acts" appears regularly in Outside Magazine. His new collection of short stories is called Blood Line, and his second collection of science essays will be published soon.

David Dinges, a professor of psychology at The University of Pennsylvania. He has recently started a chronobiology research lab to study how cycles of time and light can affect behavior and mental health. He will discuss our internal biological clock, sleep disorders, and how shortage of light can affect our moods.

Book Critic John Leonard reviews An Urchin in the Storm, a collection of essays by biologist Stephen Jay Gould.

Scientist and writer James Trefil has a new book about meteorology called Meditations at Sunset. He hopes that a better understanding of the rules of physics will help people appreciate the mysteries of nature.

Stewart Hoover is a research scholar at the Annenberg School of Communications at the University of Pennsylvania who specializes in the impact of communications technology on culture. In recent years, many have deemed religious television programming controversial. Many mainline church leaders fear the effect such programming will have on local churches. Hoover, along with George Gerbner, Larry Gross, Michael Morgan, and Nancy Signorielli, has just conducted a study on religious television programming.

Researcher Dian Fossey returns to Fresh Air to share more of her findings about gorillas' social and sexual behavior, and her experience confronting poachers, all of which she details in a new book.

Gerontologist Roy Walford is currently researching the aging process and how to extend life expectancy. His new book "Maximum Life Span," explores the theory he is currently developing on using caloric restriction, or what Walford calls "under nutrition," to extend life expectancy. Walford has been on the faculty of the University of California, Los Angeles (UCLA) since 1954, and has won many awards for his research and work.

Hans Bethe won the 1967 Nobel Prize for Physics for determining the nuclear processes that power the sun and stars. Bethe was also involved in the creation of the atom and hydrogen bombs at the Los Alamos project during World War II. Bethe is now an activist for a nuclear freeze, and co-authored a New York Times op-ed on the topic. He joins the show to discuss the development and future of nuclear arms.

Dian Fossey has spent 14 years studying the social, behavioral, and communication patterns of mountain gorillas in Rwanda and Uganda. Now a professor at Cornell University, she shares her findings with Fresh Air's Terry Gross.