Primatologist Frans de Waal, whose study of chimpanzees and apes helped reveal the reconciliatory and empathic nature of primates -- including humans -- has died at age 75, said the university where he worked for decades.
De Waal, who won multiple awards over his long career, wrote several popular books and in 2007 made Time magazine's list of the world's 100 most influential people, succumbed to stomach cancer on March 14, Emory University said Saturday in a statement and tribute on its website.
The Netherlands-born scientist spent decades studying chimpanzees and apes, and his biological research eventually helped debunk the theory that primates including humans were naturally "nasty" and aggressive competitors.
"De Waal shattered long-held ideas about what it means to be an animal and a human," Emory, based in Atlanta in the US state of Georgia, said in its statement.
"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."
Lynne Nygaard, chair of Emory's Department of Psychology, remembered de Waal as "an extraordinarily deep thinker" who could offer "insights that cut across disciplines."
"It's difficult to sum up the enormity of Frans de Waal's impact, both globally and here at Emory," she said in the statement.
De Waal wrote popular and critically acclaimed books that helped explain his research to a broader public, including "Our Inner Ape," "Different" and "Peacemaking Among Primates."
"I've brought apes a little closer to humans but I've also brought humans down a bit," Emory quoted de Waal as saying.
The scientist was a prolific lecturer and his TED Talks have been seen millions of times, including one from 2011, when he showed the "reconciliation" exhibited by chimpanzees, the empathy and reciprocity of monkeys who shared food, and how such social behavior compared to their human cousins.
"Humanity is actually much more cooperative and empathic than given credit for," he said in the lecture.
De Waal won the E.O. Wilson Literary Science Writing Award in 2020, and in 2021 he won the Ig Nobel Prize, a satiric award that honors achievements that make people laugh, and then make them think.