Primatologist and author Frans de Waal, whose research and writing helped shape human understanding of animals, particularly primates, died Thursday at his home in Stone Mountain, Georgia, the New York Times reports. He was 75. His wife, Catherine Marin, saidthe cause of death was stomach cancer.

De Waal, who was born in the Netherlands, was the author of at least 13 books, including Different (2022), Mama’s Last Hug (2019), Are We Smart Enough To Know How Smart Animals Are? (2016), and Our Inner Ape (2005), as well as his 1982 breakthrough Chimpanzee Politics: Power and Sex Among Apes. The recipient of many science and literary prizes, he was included in Time magazine’s 2007 list of the 100 most influential people in the world. His TED Talks have racked up millions of views.

In an obituary, Emory University, where de Waal was a physiology professor and conducted research on chimpanzees and apes at the school’s Yerkes National Primate Research Center, said he “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, according to the university. “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.”

In its obituary, the Times credits de Wall with launching “a torrent of discussion about animal sexuality” and popularizing the concept of the “alpha male,” although, the paper said, “neither of those accomplishments had much to do with the core of his thought. “

The episodes he chronicled in his books indicated that “that primates had cognition” and “were capable of learning, remembering and passing down new skills across generations,” the Times noted.

On X, neuropsychologist, psychoanalyst, and author Mark Solmsremembered de Waal, calling his death “a loss to science and humanity.”

Amy Reiter is a writer in Brooklyn.