Shelters often mislabel dog breeds. But should we be labeling them at all?

Pit bulls get a bad rap, which is especially vexing given that no one actually knows exactly what a pit bull is. There's no unified definition, because "pit bull" is not a recognized breed. But the label can have devastating consequences for dogs in shelters, who are perceived as less adoptable because of their purported heritage. In recent years, especially with the advent of genetic testing, some researchers have a new idea: just stop labelling mixed-breed dogs altogether. Researchers at Arizona State University decided to do a large-scale analysis of shelter dogs by looking at every pup that came through the doors of two animal shelters, one in Phoenix, AZ and one in San Diego, CA.