I been asking myself that very question for a long long time! Interesting video and yet so disturbing seeing some of these breeds and mutations, I cringed seeing those massive chains on that one breed... I don't believe any animal is born mean or dangerous, it's what people have done to them to make them that way. Any breed of animal I've ever had, I did quite a bit of research on the breed before getting one. There have been many that I passed up because I was unable to provide what the breed needed. When I adopted my Shirley, sure I could have gone and purchased a registered puppy, but with my physical limitations I would not be able to properly care for or train a puppy. I can't get down in the floor to play and meet the needs of a puppy. So I decided to adopt an adult in need of a good loving home that my physical limitations would not hinder the growth or mental stability as a puppy would need.