In the U.S., more than half of households have a pet – usually more than one. They’re usually considered members of the family, and some of us even call them our “furry children.” The strength of the human-pet bond tells us as much or more about ourselves as it does about our pets, and in this eBook, Our Furry Friends: The Science of Pets, we look at why dogs and cats behave the way they do and what makes our bond with them so strong. In her opening article, “Pets: Why Do We Have Them?” Daisy Yuhas discusses the variety of reasons for pet ownership, including our emotional need to nurture other living things. This emotional bond brings its own benefits such as social support and reduced stress, making us happier and healthier. How and why pets came to adopt humans is another question entirely, and two articles, “From Wolf to Dog” and “The Taming of the Cat,” look at the evolution of the human relationship with dogs and cats, respectively. Pets’ behavior is examined further in several articles, including “The World According to Dogs,” in which Julie Hecht deciphers what it means when a dog won’t play and whether that “guilty look” really indicates a feeling of responsibility. Meanwhile, in “The Inner Life of Cats,” Kate Wong investigates feline quirks such as why cats purr or bring their kills to their humans. Finally, all pet owners know that animals feel things, and science is starting to agree. As we learn in “Do Animals Feel Empathy?” and “When Animals Mourn,” many species grieve over the loss of relatives or close companions, indicating that empathy and grief could have neural and evolutionary roots.