Part of the reasons that some statistics say Pit Bulls are always the ones involved in human attacks is because ANY dog who is involved in an attack that has a larger sized head is automatically labeled a pit bull or a pit bull mix. Some bully breeds WERE developed for human aggression and some of those breeds are gaining popularity and being crossed onto other bull breeds. But no matter what is really behind the genetics, they are always labeled Pit bulls. This is a fun little test......see if YOU can spot the pit bull on this link. Only one of the 25 dogs on this test is actually a pit bull.
http://www.pitbullsontheweb.com/petbull/findpit.html
http://www.pitbullsontheweb.com/petbull/findpit.html