Mama briefly achieved international fame after her death in April 2016. The 59-year-old chimpanzee was an astute leader and diplomat who lived a fascinating life, and she could have been famous for many reasons, as primatologist Frans de Waal explains in his new book, “Mama’s Last Hug.” She ended up going viral, however, because of the way she embraced an old friend who had come to tell her goodbye.
That friend was Jan van Hooff, a then-79-year-old Dutch biologist who had known Mama since 1972. Although the elderly Mama was lethargic and unresponsive to most visitors, she lit up at the sight of van Hooff, not just reaching out to hug him but also grinning widely and gently patting his head with her fingers. It was a powerful moment full of relatable emotion, and it was captured on a cellphone video that has been viewed more than 10.5 million times in the three years since.
Mama died a week after this reunion. The video was then shown on national TV in the Netherlands, where viewers were “extremely moved,” according to de Waal, with many posting comments online or sending letters to van Hooff describing how they had wept. The same reaction later echoed around the world via YouTube.
People felt sad partly due to the context of Mama’s death, de Waal says, but also because of “the very human-like way she had hugged Jan,” including the rhythmic patting with her fingers. This common feature of human hugs also occurs in other primates, he points out. Chimps sometimes use it to soothe a crying infant.
“For the first time, they realized that a gesture that looks quintessentially human is in fact a general primate pattern,” de Waal writes in his new book. “It’s often in the little things that we best see evolutionary connections.”
Those connections are definitely worth seeing, and not just to help YouTube viewers empathize with a dying chimpanzee’s nostalgia. While “Mama’s Last Hug” offers some incredible anecdotes from its title character’s life, her final embrace is mainly a jumping-off point to explore the wider world of animal emotions — including, as the book’s subtitle puts it, “what they can tell us about ourselves.”
De Waal, one of the world’s best-known primatologists, has spent decades exploring the evolutionary links between humans and other animals, especially our fellow primates. He has written hundreds of scientific articles and more than a dozen popular science books, including “Chimpanzee Politics” (1982), “Our Inner Ape” (2005) and “Are We Smart Enough to Know How Smart Animals Are?” (2016).
After training as a zoologist and ethologist under van Hooff in the Netherlands, de Waal received his Ph.D. in biology from Utrecht University in 1977. He moved to the U.S. in 1981, eventually taking joint positions at Emory University and the Yerkes National Primate Research Center in Atlanta. He retired from research a few years ago, and this summer he will retire from teaching, too.
For most of de Waal’s career, he has chafed under the way behavioral scientists have traditionally viewed the mental capacities of nonhuman animals. Justifiably cautious about projecting human traits onto other species — a habit known as anthropomorphism — many 20th-century scientists went too far in the other direction, according to de Waal, adopting a stance he calls “anthropodenial.”
“Scientists have been trained to avoid the topic, even though we talk about power struggles and reconciliation behavior, emotions and feelings, internal states in general, cognition and mental processes — all the words we are supposed to avoid,” de Waal tells MNN in a phone interview. “I think it comes from a century-long indoctrination by behaviorists,” he adds, specifically crediting the American brand of behaviorism pioneered last century by psychologist B.F. Skinner, who saw nonhuman animals as driven almost entirely by instinct rather than intelligence or emotion.
De Waal cites one prominent neuroscientist who is so wary of anthropomorphizing that he stopped referring to “fear” in the rats he studies, instead merely speaking of “survival circuits” in their brains to avoid any parallels with subjective human experiences. “It would be like saying that both horses and humans seem to get thirsty on a hot day,” de Waal writes in his new book, “but in horses we should call it ‘water need’ because it is unclear that they feel anything.”
While this caution is rooted in scientific rigor, it has brought ridicule on scientists who study emotions and internal states of nonhuman animals. “We are very often accused of anthropomorphism as soon as you use ‘human’ terminology,” de Waal says. It’s true that we can’t be sure how other species feel when they experience an emotion, but we can’t be sure how other humans feel, either — even if they try to tell us. “What humans tell us about their feelings is often incomplete, sometimes plainly wrong, and always modified for public consumption,” de Waal writes. And we would need to ignore a lot of evidence to believe that human emotions are fundamentally unique.
“Our brain is bigger, true, but it’s just a more powerful computer, not a different computer,” de Waal says. To believe otherwise is “highly unreasonable,” he argues, “given how similarly the emotions manifest themselves in animal and human bodies, and how alike all mammalian brains are down to the details of neurotransmitters, neural organization, blood supply and so on”.