 Barbara J. King is an emerita professor of anthropology at William & Mary and a research fellow at PanWorks. That's a think tank focused on animal well-being. She's also author of How Animals Grieve. And Susana Monceau, she's an assistant professor in the Department of Logic, History and Philosophy of Science at the National Distance Education University in Spain. Her new book, Playing Possum, How Animals Understand Death.