[Note: Frans de Waal suggested we provide a complete listing for the Scientific American program PRIMATE TIME PRIMATES. Jill Singer, with Chedd-Angier, the Production Company for the program, kindly supplied us with this fuller description. A loan copy will be available from the WRPRC Audiovisual Archive after the program airs.] SCIENTIFIC AMERICAN FRONTIERS PRIME TIME PRIMATES SHOW OUTLINE 1. DO CHIMPS HAVE CULTURE? To examine the question of culture, Yerkes psychologist Michael Tomasello studies how children and chimpanzees learn to use tools. He has discovered a crucial difference: children will watch someone using a tool, and then imitate that person's exact method of tool use. Chimps will observe someone using a tool, explore the tool themselves, and then figure out their own method of using it. Each chimp will "reinvent the wheel," making cultural transmission almost impossible. 2. DO PRIMATES SHARE? In his experiments with capuchin monkeys and chimpanzees, Yerkes Frans de Waal has discovered that there is a Golden Rule among primates: they do unto others as they would have others do unto them. They practice reciprocity: if monkey A shares food with monkey B on one day, then monkey B will share with monkey A the next. And food is not the only currency in this barter system: if monkey A grooms monkey B, then monkey B is more likely to share food with monkey A. 3. DOES CROWDING LEAD TO AGGRESSION? Primatologist Peter Judge challenges the common assumption that crowding breeds aggression: in his study of rhesus monkeys, he has found that crowding breeds coping. He observed 3 groups of rhesus monkeys in 3 different population densities: free-ranging monkeys on Morgan Island, South Carolina; a captive group living in a large enclosure, and a group housed in a small cage. The population density in the cage was 6000 times greater than on the Island. But the rate of aggression hardly increased at all. What did change were the "coping behaviors," like appeasement, reconciliation, and grooming. 4. NEWBORN CHIMPS At the nursery of the Yerkes Primate Center, Kim Bard is trying to figure out the best way to raise newborn chimps who cannot be raised by their mothers. Humans provide 4 hours a day of close physical contact; in addition, juvenile chimps are trained to nurture the newborns. 5. THE AYE-AYE The aye-aye, a lemur native to Madagascar, is considered the most endangered primate species. It is a very bizarre creature, with bat-like ears, huge bulging eyes, rat-like snout, and a middle finger twice as long as its other digits. At the Duke University Primate Center, a full-scale effort is being made to save the aye-aye, and the first one was born in captivity last year. Psychologist Carl Erickson is now studying the unique intelligence and sensory perception of this unusual animal. 6. CAN CHIMPS DO ARITHMETIC? Sally Boysen at Ohio State University has demonstrated that chimps have a surprising ability to understand numbers. Her chimps can count, use Arabic numerals, do addition problems, and even understand fractions. 7. BEING THE LEADER ISN'T ALL IT'S CRACKED UP TO BE On Cayo Santiago Island in Puerto Rico, John Berard studies the rigid dominance hierarhcy of rhesus monkeys. And he has made an intriguing discovery: females prefer to mate not with the dominant male, but with wandering, low-ranking strangers instead. He watches mating behavior and then performs DNA analysis to confirm his findings. He also studies the offspring of dominant females and has found that here too, dominance is not always an advantage. These youngsters, who are treated like royalty within the family group, fare poorly when they are forced to migrate.