No one knows the tiny Saimiri collinsi species of squirrel monkey living in the eastern Amazonia forests of Brazil like Anita Stone.

Anita Stone visited the Eastern Amazonia forests of Brazil in 2012 to continue her studies on squirrel monkeys.

The assistant professor of biology at California Lutheran University in Thousand Oaks has been studying the monkeys since 2000. She spent a full year in the field collecting data for her doctorate. It was the best experience of her life, she says, albeit a lonely one for much of the time. She returns to her native Brazil for about two months every summer to monitor the monkeys’ behavior. This summer, she will take two Cal Lutheran undergraduate students with her to observe the mating season.

“I love nature and just think it’s important to know how it works,” Stone said.

Her dad is American and her mother is Indian, but the couple emigrated to Brazil before Stone was born. She moved to Ohio when she was 17 to attend Oberlin College. She knew she wanted to pursue something related to ecology. Having grown up along Brazil’s coast, she initially thought about becoming a marine biologist. But midway through college, she spent a summer at a tropical biology and conservation workshop in Costa Rica and fell in love with tropical forests, and monkeys.

“I said, ‘This is it.’ ”

After earning a bachelor’s degree in biology with a minor in psychology from Oberlin, Stone began working on her doctorate in ecology and evolutionary biology at the University of Illinois at Urbana-Champaign. During her first year, she zeroed in on squirrel monkeys.

Stone can get close to the squirrel monkeys living in the forests of eastern Amazonia because they prefer to hang out low in the tree canopy and they don’t fear humans, always having been left alone.

“They were curious at first. The juveniles would just look at me. But after maybe two months, they became what you would call habituated. To them, I was just part of their landscape,” Stone said.

That doesn’t mean the monkeys are easy subjects, though. It’s difficult to recognize individuals because there are 50 of them in a social group, they move quickly and they’re so small that they don’t have a lot of distinguishing features.

“They’re only 2 pounds, max. Max. That’s like a big one,” Stone said.

In 2012, Stone trapped some of the monkeys to mark them with collars and microchips and get blood samples. None of the standard methods of trapping primates worked with these smart monkeys, though, so her team had to develop a new method, which they later published.

Body size differences enable Stone to distinguish males from females. The females dominate the males, and even juveniles bully males in the mating season.

“The males tend to stay on the periphery of the group. They don’t even come near the mothers with the babies,” the behavioral ecologist said. “When the mating season comes, the males come in, but once it is over, they go back to the outer corners of the group.”

Stone has noticed that males with bulked-up upper bodies, or “fattened males,” spend more time with females during the mating season and that females ignore the skinnier males. It may be that, in the minds of these female squirrel monkeys, fatter is sexier. The bulk also gives the males an advantage in intimidating other males.

“The males are fascinating to me because of the whole fattening thing. No other primate does this in quite the same way,” Stone said.

Stone has tied her research to education from the beginning. Toward the end of her yearlong research project in Brazil, she began teaching about conservation in the nearby village to show residents what she was doing and clear up their misconceptions about the creatures of the forest.

At Cal Lutheran, she has started classes in primate ecology and the biology of sex and gender. She is also part of a new program that supports and provides opportunities for students in science, technology, engineering and mathematics.

“I went to a small university myself and it was important to me to teach at a place where I could give similar experiences to my students — small class sizes, more personal attention and the opportunity for undergraduates to participate in my research.”

Anita Stone joined the California Lutheran University faculty as an assistant professor of biology in August. A behavioral ecologist specializing in neotropical primates, she focuses her research on life histories, social behavior and sexual selection.

Karin Grennan is the media relations manager for California Lutheran University. Kevin Matthews is the university editor at California Lutheran University Magazine.

Off Campus is a new series that will appear periodically featuring professors from California Lutheran University, California State University, Channel Islands, and the Ventura County Community College District and their lives and passions that extend beyond their regular teaching careers and enhance their educating experience. This series came to be through invitation to campus’ media professionals to find and present qualified educators.