Dogs and Domesticated Herd Animals

"I've always been interested in why humans have all this assortment of illnesses," he says. "For the most part, your general animal doesn't deal with that stuff." But wild animals might get hurt or come down with something every now and then; dogs do sometimes because they're more connected to humans than other animals. And domesticated animals start picking up human attributes such as 'cancer,' which is not a disease but will explain why dogs are gross.