Monkey See, Monkey Say

Marc Hauser studies primates for clues to the origins of language

By Alvin Powell

Contributing Writer

Primate vocalizations may be just screeches and howls to most of us, but to Psychology Professor Marc Hauser, they're more.

How much more, he's still figuring out.

In three distinct locations -- his 10th floor lab in William James Hall, the trees of the Puerto Rican Island of Cayo Santiago, and the jungle of Kibale National Park in Uganda -- Hauser is exploring the frontiers of communication: searching for the beginnings of human language and for traces of language among primates.

"It's fun because there's a phenomenal challenge facing me, similar to work on human infants -- I can't ask [the primates] what they think," Hauser said. "I really enjoy thinking up new ways to ask the question."

Hauser, promoted to professor on July 1, says his work crosses disciplinary boundaries, incorporating aspects of biology and anthropology. He has been widely published, and his 1996 book, The Evolution of Communication, won critical praise for its presentation of the many theories of how communication arose.

Hauser's appointment continues the Psychology Department's tradition of hiring faculty who are studying the evolution of the mind, according to Sheldon White, the department's chair and the John Lindsley Professor of Psychology.

"This department, since very near the beginning, has tried to have people onboard dealing with the early evolution of the human mind," White said, adding that Hauser is different from many others on the faculty in that he has a substantial background in biology.

"What Hauser represents is a close, careful examination of animal behavior, which he attempts to link with a close, careful examination of human behavior," White said.

Monkey See, Monkey Say

Much of Hauser's job is designing and conducting experiments to test the cognitive and communication abilities of subjects who can't speak -- a task that requires a great deal of creativity and intuition. A difficult but important aspect of this task is to devise tests that can be used unchanged by different species so the results can be compared.

"In my field, lots of work is really low-tech. It's really the idea that's going to carry the day," Hauser said. "My job is an incredible amount of fun."

Hauser's research also requires him to spend time in the field. This summer, Hauser traveled in Africa, searching for evidence of vocal dialects in vervet monkeys from different regions. Vervets, he said, are ideal experimental subjects, because they are very adaptable and can be naturally found in deserts, in the savannah, and in tropical forests.

In addition, vervets have been found to give three different alarm calls: one if the danger is a leopard, one if it is a snake, and one for other kinds of dangers. The knowledge of the alarm calls and broad range of environments in which vervets are found combine to make them ideal subjects to search for evidence of dialects in animals.

The initial results from the field will be analyzed and followed by tests in the lab, Hauser said. Hauser hopes to have preliminary data ready by the middle of next year.

Philosopher Turned Scientist

In coming to Harvard, Hauser has come full circle, at least geographically. He was born in Cambridge, just blocks from the University. His father, Jacques, was a Harvard graduate student in physics.

Though he got his early start here, Hauser spent most of his childhood in Summit, N.J. As an undergraduate at Bucknell University, Hauser was interested in philosophy, as his father had been. Jacques Hauser repeated to Marc the advice given him: "It's fine as a hobby, not as a career."

So Hauser turned to his other love, biology. He took a course in animal behavior and liked it so much he decided to make it his major.

Hauser received his bachelor's degree from Bucknell University in 1981 and his Ph.D. from the University of California at Los Angeles in 1987. He had three postdoctoral fellowships -- at the University of Michigan, at Rockefeller University, and at the University of California, Davis.

Hauser came to Harvard in 1992 as an assistant professor in the departments of Anthropology and Psychology and in the Program in Neuroscience. He was promoted to associate professor in 1995 and to professor this past July.

Before coming to Harvard, Hauser was a lecturer and researcher at the departments of Psychology and Zoology at the University of California, Davis.

In addition to his studies of monkeys and chimpanzees, Hauser is currently involved with two collaborative research projects comparing the development of language and numerical skills in human infants and monkeys. Those projects are interesting, he said, because when they begin, the monkeys are far ahead of the infants.

"The monkeys right now are 'killing' the babies," Hauser said. "Rhesus monkeys are passing tests of numerical competence that 14-month-olds can't pass."

At some point, though, the babies begin to catch up and then pass the monkeys. The trick is figuring out why that happens.

Hauser said the numerical tests are intriguing because numbers share with language the same properties in that a finite set of elements can be combined into an infinite number of combinations.

For his part, Hauser sees two key characteristics that set humans apart from apes and monkeys. The first is that humans have a much greater capacity from birth for imitation, which helps them learn. The second is that humans have much greater impulse control, enabling them to stop themselves, for example, from doing something that seems appealing but might be harmful.

Hauser covers some of these topics in his latest project, a book called Minds Before Adam, which he hopes to complete by the spring of 1999.

One thing about Harvard that attracted Hauser is the opportunity for instructors to interact with students, he said. One of his courses is B-29, Human Behavioral Biology, to which a lot of the students come from backgrounds in the humanities. Hauser tries to relate the course's science to topical debates over things like the death penalty.

"B-29 is an unusual course because it is the only course that gives them a biological hit on human nature," Hauser said, adding, "I really love teaching. I feel that the way to give back is by teaching."