Barbara: I have an unusual background for somebody to be writing about animals. I spent over twenty years as a physician, as a cardiologist, a professor of medicine at UCLA. One day I got a call from one of the veterinarians at the Los Angeles Zoo who wanted me to come and image the hearts of some of their animal patients. It was actually a chimpanzee who they thought had had a stroke. That experience led to a request a few weeks later to image a gorilla’s aorta and then a few months later, the heart of a lion they thought had metastatic breast cancer, and so on and so forth. What happened over the course of several years is that even though I was spending ninety-eight percent of my time at UCLA at the human hospital taking care of human beings with heart attacks and high cholesterol, etc., I was also going to the zoo periodically and joining the vets on rounds where they were talking about heart failure in a kangaroo or metastatic melanoma in a rhino, and even behavioral problems. They were talking about dosing fluoxetine, which is Prozac effectively, for some of their animals who had compulsions and anxiety. I had this aha moment. It was really an aha moment. Here I had been a professor of medicine for twenty years taking care of very advanced cardiovascular disease. I'd been teaching medical students. I really had never thought much about the so-called human diseases in non-human animals. In other words, I thought about cancer and heart disease as diseases of civilization. Those are human. I just hadn’t really looked at it from a broader perspective.