Three photos of Frans de Waal: observing monkeys, a portrait, and teaching a class

Emory primatologist Frans de Waal remembered for bringing apes ‘a little closer to humans’

Book cover for "Chimpanzee Politics"

40 years of publishing: From "Chimpanzee Politics" in 1982 to "Different" in 2022.

40 years of publishing: From "Chimpanzee Politics" in 1982 to "Different" in 2022.

Book cover for "Different"

40 years of publishing: From "Chimpanzee Politics" in 1982 to "Different" in 2022.

40 years of publishing: From "Chimpanzee Politics" in 1982 to "Different" in 2022.

Emory University primatologist Frans de Waal — who pioneered studies of animal cognition while also writing best-selling books that helped popularize the field around the globe — passed away March 14, 2024, from stomach cancer.

De Waal, Charles Howard Candler Professor Emeritus of Psychology and former director of the Living Links Center for the Advanced Study of Ape and Human Evolution at the Emory National Primate Research Center, was 75.

From his groundbreaking 1982 book “Chimpanzee Politics: Power and Sex Among Apes” to 2019’s “Mama’s Last Hug: Animal Emotions and What They Tell Us About Ourselves,” de Waal shattered long-held ideas about what it means to be an animal and a human.

“One thing that I’ve seen often in my career is claims of human uniqueness that fall away and are never heard from again,” de Waal said in 2014. “We always end up overestimating the complexity of what we do. That’s how you can sum up my career: I’ve brought apes a little closer to humans but I’ve also brought humans down a bit.”

“It’s difficult to sum up the enormity of Frans de Waal’s impact, both globally and here at Emory,” says Lynne Nygaard, chair of Emory’s Department of Psychology. “He was an extraordinarily deep thinker who could also think broadly, making insights that cut across disciplines. He was always ready to participate in an intellectual discussion.”

In addition to being a world-renowned scholar, beloved teacher and supportive colleague, “Frans was funny,” Nygaard says. “If a discussion became fraught, he could make just the right irreverent remark to get everyone to laugh and break the tension.”

40 years of publishing: From "Chimpanzee Politics" in 1982 to "Different" in 2022.

“We may accept that we are descended from apes, but it takes the likes of Frans de Waal to remind us that we haven't traveled that far.”
—TIME Magazine, Top 100 People who Shape Our World

Breaking taboos

George Romanes, a protégé of Charles Darwin, tried to connect ideas of animal consciousness and human consciousness in the late 1800s, but his theories were dismissed as anecdotal and anthropomorphic.

For nearly 100 years, the subject of the social mind of animals remained largely taboo in the scientific community. Finally, in 1976, neuroscientist Donald Griffin published his first edition of “The Question of Animal Awareness: Evolutionary Continuity of Mental Experience.” That book compiled observations suggesting animals might have thoughts worthy of exploring and that it was possible to do so in a scientifically objective way.

“Donald Griffin opened the door just a little bit and then Frans pushed it wide open. The rest is history,” says Harold Gouzoules, an Emory professor of psychology who studies primate social behavior and vocal communication.

Frans de Waal as a young scholar

De Waal wrote hundreds of peer-reviewed scientific articles comparing primate and human behavior. He demonstrated the roots of human nature in our closest living relatives through his studies of conflict resolution, reconciliation, cooperation, empathy, fairness, morality, social learning and culture in chimpanzees, bonobos and capuchin monkeys.

A prolific writer and editor, his impact reached far beyond academia through his articles for major magazines and newspapers and his 16 popular books that have been translated into 20 languages. He was a gifted speaker who wove deadpan humor into his many public talks — usually filled to capacity — about his research. His TED Talks have been viewed millions of times.

Animal emotions: In this Emory video, watch Frans de Waal discuss his 2019 book, "Mama's Last Hug."

A young Frans de Waal holds a baby monkey

Frans de Waal as a young scholar

Frans de Waal as a young scholar

Training the next generation

Through teaching and research projects, de Waal also helped train and influence many leaders in the field of animal cognition.

“Frans was a fantastic mentor, he really believed in his students,” says Sarah Brosnan, who received a PhD in 2004 in Emory’s Population Biology, Ecology and Evolution Program. Brosnan is now Distinguished University Professor of psychology at Georgia State University where she investigates the evolution of cooperation, decision-making and economic behavior among primates.

“Frans told us the best way to come up with research questions was to watch your animals and they will tell you what’s important,” recalls Brosnan.

She took his advice to heart.

One day, while Brosnan was feeding capuchin monkeys at the primate center, she tried to distract the dominant male, Ozzie, while she slipped peanuts to the others, to keep him from grabbing them all. Ozzie caught on, however, and brought Brosnan a piece of a naval orange from his enclosure, offering it in exchange for a peanut.

Oranges are generally a choice treat to monkeys, rating even higher than peanuts. “I wondered if the reason Ozzie was willing to trade a chunk of orange for a peanut was because everyone else was eating one,” she recalls.

A master of visualization

That simple question led to Brosnan and de Waal developing the famous cucumber-grape study on fairness.

Two capuchins were situated in enclosures next to one another. A researcher would ask them to do a task and if they succeeded give them a treat. The catch was one monkey was always rewarded with a piece of cucumber while the other monkey sometimes got a piece of cucumber and sometimes got a grape — a preferred treat among capuchin monkeys.

A video de Waal filmed of one of the experiments created a media sensation.

Unequal pay for equal work: When the first monkey gives the researcher a rock, she is rewarded with a cucumber slice. But watch what happens when the first monkey sees the second monkey hand the researcher a rock — and get a much tastier grape instead.

A monkey that received only cucumber appears perfectly happy until she sees her companion receive a grape. Then her behavior changes. She accepts the next piece of cucumber only to throw it back at the researcher, pounding the surface in front of the enclosure and shaking its Plexiglas walls.

“That video struck home with a lot of people,” Brosnan says. “Who hasn’t felt like that monkey that’s only getting cucumbers? Our research showed something about the evolution of the sense of human fairness.”

De Waal, a skilled visual artist and photographer, routinely videotaped experiments — long before that became common practice in labs.

“Both Frans and I used the cucumber-grape experiment video in our TED Talks,” Brosnan notes. “Frans taught his students how to write well and how to give a good presentation. You weren’t allowed to just read some text. Your slides always had to have images and videos.”

Frans de Waal in classroom writing on a white board

Animal reconciliation

Franciscus Bernardus Maria “Frans” de Waal was born in 1948 in s’Hertogenbosch, the Netherlands, where he trained as a zoologist and ethologist at three universities — Nijmegen, Groningen and Utrecht. In 1977 he received a PhD in biology from the University of Utrecht where Jan van Hooff, a Dutch biologist renowned for his research involving primates, was his mentor.

Frans de Waal as a young boy

For his dissertation, de Waal began working with the colony of chimpanzees at the Arnhem Zoo in the Netherlands. That work led to his first major discovery: chimpanzees make up after fights.

“I discovered that by just seeing how the opponents would come together after fights and kiss and embrace,” de Waal later said. “I never had trouble getting primatologists interested or convincing them, but other scientists were often skeptical. This meant conducting experiments and collecting data to convince them.”

Instead of describing the behavior he observed using a clinical term, such as “post-fight, affiliative contact,” de Waal called it reconciliation — a word, up until then, reserved for humans. This research became the basis of his book “Chimpanzee Politics,” which compared the schmoozing and scheming of chimpanzees involved in power struggles with that of human politicians.

“There really was no history of someone studying something as complex as reconciliation in animals,” says Kim Wallen, who recently retired as an Emory professor of psychology. “Frans faced a lot of challenges because he looked at questions that were outside the mainstream of animal behavior research. He persisted and carved out an area of his own.”

In 1981 de Waal moved to the United States to join the Wisconsin National Primate Research Center.

Wallen, who studied sex-related behaviors in humans and non-humans, recruited de Waal to join Emory in 1991. “His reputation preceded him,” Wallen recalls. “It was a big coup for Emory.”

A black and white photo of Frans de Waal as a child wearing a tie

Frans de Waal as a young boy

Frans de Waal as a young boy

Understanding our inner ape

At the field station of the Emory National Primate Research Center, de Waal kept a small office atop a tower. A windshield-like opening in the office overlooks a habitat where multi-generational groups of chimpanzees live outdoors.

De Waal supervised the construction of a building adjacent to the habitat for cognition research with the chimpanzees. A door would slide up allowing the chimpanzees to voluntarily come inside to try to solve a puzzle or perform a task.

A large part of de Waal’s research also encompassed bonobos, what he called “the forgotten ape,” including studies of bonobos in the San Diego Zoo and in the Democratic Republic of Congo. Both the chimpanzee and the bonobo are our genetic twins, but for 1.5% difference in DNA. And while chimpanzees rely on aggression to solve problems, the peaceable, sex-loving, female-dominated bonobos are so chill de Waal described them as “the hippies of the primate world.”

In his 2005 book, “Our Inner Ape,” a New York Times Notable Book of the Year, he used these contrasting ape societies as the context to examine some of the most fundamental, complex and intense manifestations of human nature.

“We have an enormous spectrum of behavior, so don’t believe claims that we are inherently nasty, aggressive, selfish and uncooperative,” de Waal said in a 2006 interview. “My argument is that we have the potential to be everything we want to be. Our job is to bring out what we want.”

Frans de Waal holding binoculars as he looks down from an observation tower to watch chimpanzees

Making the most of every minute

In addition to his extreme productivity as a scientist, teacher and communicator, de Waal was a social animal, especially when it came to his students.

“I think Frans came across sometimes as reserved but he wasn’t like that once you got to know him,” Brosnan says. “He was so much fun. He would hold what he called ‘simian soirees’ at his house where graduate students would gather to talk. He was a fantastic piano player and he would play for us.”

De Waal retired from Emory in 2019 but remained active. He was in demand internationally and traveled widely, attending conferences and giving public talks. “The number of talks he would give in a year was always off-the-charts impressive,” Gouzoules said. “It was almost like a rock star touring around.”

De Waal also continued writing, publishing “Different: Gender Through the Eyes of a Primatologist” in 2022. In 2023, he made an appearance in New York for a public discussion with film icon Isabella Rossellini about the book, and what we may learn about sex and gender from primate studies.

Frans de Waal speaking at the Phil.Cologne international festival for philosophy in Germany in June 2023. (Photo by Ying Tang/NurPhoto via AP)

De Waal made his home in Stone Mountain, Georgia, where he lived with his wife of more than 40 years, Catherine Marin. The couple also maintained an apartment in the Netherlands where he had an affiliation with the University of Utrecht.

De Waal was made a Knight of the Order of the Netherlands Lion In 2010 and elected to the American Academy of Arts and Sciences in 2008 and the National Academy of Sciences in 2004. Among his many awards are the E.O. Wilson Literary Science Writing Award (2020), the Galileo Prize (2014), the Ig Nobel Prize (2012), Discover magazine’s “47 All-time Great Minds of Science” (2011), Time magazine’s 100 world’s most influential people (2007), the American Psychological Foundation Arthur W. Staats Award (2005) and the Los Angeles Times Book Award for “Peacemaking Among Primates” (1989).

Frans de Waal wearing a headset microphone for a speech

Frans de Waal speaking at the Phil.Cologne international festival for philosophy in Germany in June 2023. (Photo by Ying Tang/NurPhoto via AP)

Frans de Waal speaking at the Phil.Cologne international festival for philosophy in Germany in June 2023. (Photo by Ying Tang/NurPhoto via AP)

Frans de Waal: Highlights from a career exploring animal and human behavior

1948: Born in s’Hertogenbosch, the Netherlands

1970s: Trained as a zoologist and ethologist at three Dutch universities (Nijmegen, Groningen and Utrecht)

1975: Began working with chimpanzees at the Arnhem Zoo (the Netherlands)

1977: Received PhD in biology from the University of Utrecht

1981: Joined the Wisconsin National Primate Research Center, focused on reconciliation behavior in monkeys 

1982: Published first book, “Chimpanzee Politics,” which compared the schmoozing and scheming of chimpanzees involved in power struggles with that of human politicians

1984: Began working with bonobos (San Diego Zoo) and chimpanzees (Emory National Primate Research Center)

1989: Published “Peacemaking Among Primates

1991: Joined Emory University’s Department of Psychology and National Primate Research Center, and began mentoring graduate students and post-doctoral fellows

1993: Elected to the Royal Dutch Academy of Sciences

1996: Published “Good Natured: The Origins of Right and Wrong in Humans and Other Animals

1997: Published “Bonobo: The Forgotten Ape

2001: Published “The Ape and the Sushi Master: Cultural Reflections by a Primatologist

2004: Elected to the National Academy of Sciences

2005: Published “Our Inner Ape.” Elected to the American Philosophical Society

2006: Published “Primates and Philosophers: How Morality Evolved

2007: Named one of TIME magazine’s Top 100 People Who Shape Our World

2008: Elected Fellow of the American Academy of Arts & Sciences (AAAS)

2010: Knighted: Order of the Netherlands Lion. Published “The Age of Empathy: Nature’s Lessons for a Kinder Society

2014: Published “The Bonobo and the Atheist: In Search of Humanism Among the Primates

2016: Published “Are We Smart Enough To Know How Smart Animals Are?

2019: Published “Mama’s Last Hug: Animal Emotions and What They Tell Us About Ourselves.” Retired from Emory University.

2022: Published “Different: Gender Through the Eyes of a Primatologist

Story by Carol Clark. Title center portrait photo by Catherine Marin. Other photos by Emory Photo/Video or courtesy unless noted. Design by Laura Douglas-Brown.

Frans de Waal teaching a class by a white board

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