A quick consultation with Google provides this basic definition of the noun "breed": A stock of animals or plants within a species having a distinctive appearance and typically having been developed by deliberate selection.
It was popularly believed that our domestic dogs descended from wild wolves tamed by humans, but more recent research indicates that domestic dogs evolved gradually from canine ancestors in response to conditions in their environment, adapting themselves to a niche on the fringes of human civilization.
These canids differed from wolves in that they were less fearful of humans. They scavenged food from human garbage dumps, living in close proximity to man. These early "village dogs" would have been killed off had they presented a threat, but because they were able to coexist peacefully with humans, their destiny connected with ours, and Canis Familiaris became man's best friend.
Of course, there is no such range diversity in human biology. What diversity of human appearance does exist is extremely minor compared to that found among the population of the domestic dog. We're all humans, and respond in similar ways to given environmental conditions. In other words, there is only one human race, and the concept of different breeds as in the domestic dog simply has no parallel in humanity.
But I digress. The point I want to make here is that Canid DNA is incredibly adaptable, and that the various breeds of domestic dog have taken on distinct, breed specific characteristics, in response to deliberate efforts by humans to select for those very characteristics. For instance, pointers were bred to point to waterfowl, while retrievers were bred to retrieve downed waterfowl, with a soft mouth. Sheep herding breeds arose from selection for the ability and inclination to herd sheep. Livestock guardians were bred to protect weaker creatures under their care. Each of these working breeds was equipped, over time, with the skills to do it's specific job, from birth.
Beginning in the Elizabethan era, bull dogs were bred by selecting for temperament and physical characteristics useful in dogs which would torture animals - for instance de-horned bulls or de-clawed bears - for "sport".
When bull-baiting was outlawed in 1835, the "sportsmen" turned to dog fighting, and bred specifically for those characteristics best suited to a life in the fighting pit, tearing apart dogs (A bit of terrier was added to the bull dog for more energy, creating the "bull & terrier"). Such characteristics, copiously documented in diverse places, include, but are not limited to, a hair trigger attack reflex, a determination to continue attacking the victim, ignoring signals of submission, as well as injury to itself, and a freakish insensitivity to pain. This collection of traits characterizes the "pit bull", or the "pit fighting bull dog", which, though called by various names over time, has always displayed the distinctive traits which speak of its original purpose.
There's an old saying "You can take the dog out of the fight, but you can't take the fight out of the dog". Just as frustrated border collies without sheep to herd will take to herding children, frustrated pit bulls, without opponents in the pit to attack, will escape confinement and go looking for neighborhood pets to kill. The propensity for a pit bull to jump out of a moving car or a second story window to attack and kill a little dog is well documented, as is the rather breed specific pit bull behavior of finding ways into other people's houses to torture and kill the animals inside. There have been several such cases just within the past few weeks, and such nightmares are truly heartbreaking for anyone who has the least bit of compassion for animals.
The foregoing sets the stage for the question: If we have deliberately bred lines of dogs for centuries to produce breed-specific characteristics, why is it somehow "racist" to note the existence of these very breed specific characteristics which we've deliberately produced?
If we can accept the fact that, for instance, border collies must have a job to do, and their job is herding, because it's in their DNA, why do we deny all genetic influence when it comes to pit bulls? These bully breeds are working dogs too, and their work is killing. I'm at a loss as to how the pit bull propaganda machine continues to condemn "breedism", as though there are no genetic factors in a dog's behavior. They speak as though a pit bull were no different from a lab.
Why does the pit propaganda machine shout "racism" and speak nonsensically of "condemning a breed for the actions of a few" when that's not the issue at all? At issue here is our ability to recognize that specific breeds were created with specific purposes. We deny reality at our peril - a quick look at the statistics for serious and fatal injuries from dog attacks over the past 30 years makes it clear that breed, more than anything else, is the most relevant factor, not the owner and not the upbringing.
Bottom line: It's absurd to pretend that breed specific characteristics which were deliberately created by humans don't exist. And to call those who recognize these breed specific characteristics "racist" reveals a profound ignorance on the part of the accuser.
A final thought: When someone speaks of the unfairness of "killing off a breed" what they are actually talking about is eliminating a specific set of characteristics which have proven to be a problem. The fact that sadistic humans created a "breed" to torture animals is no mandate to continue the existence of said breed. Nobody has suggested killing off the domestic dog - only those man-made expressions of temperament and behaviors which have proven to be harmful and cruel.
Coppinger, Dogs, from amazon.com
Semyonova, The 100 silliest things people say about dogs, from amazon.com