Frans de Waal is the author of the New York Times bestseller Are We Smart Enough to Know How Smart Animals Are?, Mama's Last Hug: Animal Emotions and What They Teach Us about Ourselves, and Different: What Apes Can Teach Us About Gender, among many other books. Named one of Time's 100 Most Influential People, he was the emeritus C. H. Candler Professor of Psychology at Emory University and emeritus Distinguished Professor at the University of Utrecht. He died in 2024.