Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
SAF Archives  search ask the scientists in the classroom cool science

Guide Index

Keeping the Peace

Chimp Manners

Monkey See, Monkey Do?

Chimps Count

Finger Food

The Mating Game
in the classroom


Like humans, young chimpanzees are completely dependent on their mothers for a long time. But chimp mothers reared in captivity do not know how to be good mothers and are unable to care for their babies. Primatologists at the Yerkes Primate Research Center in Atlanta are training female chimps to learn mothering and nurturing skills naturally acquired in the wild. For the human trainers, the challenge is to raise baby chimps to be good chimps.

Curriculum Links
Activity: Why Do Animals Do What They Do?



placental mammals

niche, tropical forests

animal behavior


good citizenship

genetics, reproduction

effective parenting,
learning, memory

ACTIVITY: Why Do Animals Do What They Do?

Scientists have invested many years of research in trying to puzzle out what causes an animal to behave the way it does -- is the behavior instinctive, learned, or a combination of genes and the environment? Currently, animal behaviorists (ethologists, sociobiologists, psychologists, primatologists and others) acknowledge that the answers are not as simple as was once assumed. Genes may play an even greater role in determining behavior than was previously recognized. While the debate once pitted nature (instinctive behavior) against nurture (learned or modeled), many scientists now agree that nature and nurture play vital roles, and that much behavior is the result of some interaction between instinct and the environment.


Divide into cooperative groups. Each group will review the specific animal behaviors listed below and decide what factors determine the particular behavior -- is it instinctive and somehow genetically programmed, or is it learned by watching another member of the species? Or, is the behavior actually the result of a combination of factors? Each group should compare its findings with the other groups. If you wish, add other behaviors to the list. You'll find hints about some of these behaviors in "Prime-Time Primates."

  • Birds building nests in springtime
  • Chimps using sticks to find termites
  • Human toddlers sharing toys
  • A dog burying a bone
  • A human mother comforting its crying infant
  • A monkey grooming another monkey
  • Cats bringing their prey to their owners
  • Rhesus monkeys choosing a mate
  • Squirrels burying acorns in the fall
  • Salmon swimming upstream to spawn

  • Ethologists -- scientists who study animal behavior -- spend many hours patiently observing their subjects and noting behavior. Primatologists, such as those you've seen on Frontiers, are also ethologists.

  • You can model what ethologists do by collecting raw data about an animal you observe in the yard or the countryside. Or, watch your cat, dog or other pet very carefully for an extended period of time and write down everything the animal does. Can you find any patterns? Is the animal's behavior the same from day to day? Are there any seasonal variations? Write your observations in a report or chart (an ethogram).

  • Some behaviors, particularly courting and aggressive behaviors, are species-specific and repeated from generation to generation. What stimulates the behavior? Biologists believe inherited behaviors are stimulated by specific cues, which they call releasers or sign stimuli.

  • Look back at some of the animal behaviors in activity A. See if you can figure out the cues for behaviors such as the nest-building of birds. Is it environmental? Seasonal? Hormonal? Temperature-dependent? What causes the animal to perform a certain behavior? Consider the behavior of primates. How is it different from that of other species? Why is social interaction important? Do you think it's unique to primates?


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.