Just as a follow up, I was given permission to post someone's response (all names removed) that I found very insightful. I would encourage everyone to read it and if you have time would encourage everyone to read all of the posts on that other board (if you have a few days).
Oh dear, I've tried to stay quiet for a while, but it's not working. Some thoughts
-There are NO peer-reviewed published statistics on rates of human aggression by dogs of any particular breed or mix. Anti-pit advocates cite the CDC figures from the 1990s that appeared to show pits and rotties were overrepresented in the breeds responsible for fatal attacks, but those data were never peer-reviewed, and the CDC is the first to argue that they do not actually tell us anything about which breeds were indeed responsible for attacks. If anyone really cares, I can go into all the reasons these data are not usable for such comparisons.
-For similar reasons, pro-pit advocates like to cite Karen Delise's statistics showing that only about 20% of fatal attacks on people were by pits or pit-mixes, which is likely lower than the percentage of pits in the general pet population (suggesting that pits are LESS likely than other breeds to attack people). Again, as someone who has pits I might like to believe that argument, but Delise has not published her work in a peer-reviewed journal, and I believe that until she does, we can't draw any conclusions from it.
-As (name) suggested (I think it was (name)), you sure can't believe everything you read on the internet. Lots of websites argue old pit yardmen and fighters used to cull out any dog that showed any degree of human aggression, making pits especially human-friendly. Is this true? None of these studies are published or peer-reviewed, so it's hard to know. But it would be possible to find out, using archival data from the 18th and 19th centuries, and both archival sources and interviews from the 20th C. One of my colleagues. Dr Edmund Russell at U of Virginia, is in the final stages of what should be a fascinating article on the history of pits. His archival research suggests how very labile (in evolutionary terms) this breed has been. For example, in the 1800s, the style of betting on dog fights changed in England--bets were tossed into the ring, and as betting styles (a human social preference, not for the dog, but for a kind of betting) changed, the dog's phenology (shape) soon changed as well, because smaller, thinner, faster dogs could do better under the new betting conditions, which led to new fighting conditions (smaller rings), which led to selective pressures for new kinds of dogs.
Similarly, when the Irish immigration to the US intensified, many Irish families brought their pits with them, and fighting dogs were so valuable to an Irish family that the dogs lived inside with the family (something that was very rare indeed in Europe for a larger breed), and strong selection for gentleness with children seems to have begun at that point. Russell hasn't yet researched in any depth the American part of the story about pits, but someone should. (Name) asked if the pet pits that Roosevelt and Helen Keller and all the others owned in the early 20th century had actually diverged from fighting bull breeds. I emailed Russell to ask him about this, and he said he doesn't know for sure, but he's pretty certain that they hadn't--the game-bred pits were actually popular as pets, and they didn't fight other dogs in normal conditions, only in actual fighting pits. It may have been too risky to an important family investment to have a good fighting dog that would pick fights with stranger dogs on the street. The old story about game pits was that they wouldn't start a fight, but they also wouldn't end one. Is this true? Who knows.
-Many yardmen argue that "gameness" in pits is not just about fighting--it' s terrier tenacity, and it can be turned to con-specific fights, or it can be turned to farm-yard purposes, or it can be turned to agility purposes. Today, on the fighting websites, I think it is indeed used as a euphemism for "fighting". But gameness is a real quality, and my impression is that it's closely linked in pre-1950s pits with the gentleness toward children and people. This is just an impression (although many pit breeders argue that it's true, I don't know of any data that have been gathered to support the hypothesis. It could be tested, however).
-Conspecific aggression that leads to fatalities is actually surprisingly common in many species, including wild canids (and it's also observed in feral dogs and village dogs.) In fact, it's quite common in the evolutionary history of many group-living organisms. We would like to hope that such aggression is rarely fatal, but it's actually quite often fatal.
As a wildlife ecologist (I trained in the evolutionary ecology of social behavior, although I now work in epigenetics) , I know of course that dogs aren't exactly wolves. But whoever pointed out the wild wolves do often kill other wolves is entirely correct. Recent and very interesting research supports the (depressing) hypothesis that the altruistic behavior in social mammals seems able to evolve only when there's a high level of fatal conspecific aggression. This may seem contradictory, but when you think about it, it makes (depressing) sense. In small groups, wild canids and people will act for the benefit of the others in the group even when they don't share genetic material. This was long a theoretical puzzle for evolutionary biologists, but evidence (both theoretical modelling studies and empirical evidence) supports the argument that altruism evolves when high levels of fatal conspecific aggression exists between groups. Kind behavior, in other words, toward the same species seems to evolve because of (not in spite of) nasty violence toward the same species.
-Group-living species do indeed evolve ritualistic displays of aggression that substitute for actual fights that might result in fatal injuries--what (name) has been pointing to in "normal" dogs. But in all those species that have been studied (which isn't all that many), such ritualistic displays continue to persist in a population only when they are "backed up" by a certain frequency of actual, violent, damaging aggression. To understand this, think about painted cattle-guards versus actual metal cattle-guards as a useful metaphor. In ranch country, ranchers know they can have a certain percentage of "fake" cattle guards that are just painted onto the road--ritualistic displays of cattle-guardedness. But a certain percentage of cattle guards need to be actual grates that hurt cows' feet when they test them, or else the painted cattle guards lose their effectiveness. Ritualistic displays--roaring, snarling, mock-fights- -similarly lose their communicative power (over generations) when they never result in actual bloodshed. This doesn't mean that all dogs will fight to kill; what it does mean is that violent aggression is not abnormal; we can't point to a group of dogs that do it and say they're "abnormal" for doing it. We may not like that behavior, but the only reason it could be selected for by breeders is because the genetic potential exists for it in the larger canid gene-pool. You can't breed a dog who can fly, but you can breed a dog who can fight, because fighting played an important role in their evolutionary histories.
-Play behavior in many young predator species is an interesting combination of prey behavior ( practice for hunting) and ritualized fighting (conspecific aggression). Because of their breeding, many pitties seem to slip more quickly from play into aggressive or prey behavior than some other dog breeds, but for all dogs, play behavior has close links to both hunting and conspecific aggression. All dogs have the potential to get overaroused when playing and slide into fight behavior or prey behavior. Certain breeds, of course, are more likely to do this.
-Aggression is extraordinarily complex in evolutionary terms, and it doesn't make much sense to speak of it as one trait. Conspecific aggression (fighting) is different than predation, and in turn both are different than aggression against humans; they don't appear to be part of one continuum. Aggressive traits are polygenic (controlled by more than one gene, just like hip dysplasia), and many the genes that affect various kinds of aggression are also likely to affect many other characteristics (when one gene controls several traits, it is called pleitropy). Epigenetic influences in turn affect gene expression, and hormones affect it all. What this ends up meaning is that it wouldn't be difficult to breed for very low human aggression and high fight aggression in the same individual, and this historically is supposedly what happened with game-bred pits in the late 19th century. It probably wouldn't be impossible to breed for low human aggression, high gameness, and low fight aggression as well. But because these traits are polygenic and each of those genes are pleitropic, it's also quite easy to start messing with dogs in deleterious ways (see-- goldens: hip dysplasia; pointers: nervousness; etc)
-In the 1980s, pits became popular with inner-city adolescents, their reputation spiraled downwards. Some of this was probably connected with racism and media bias: white people became freaked out over pits because they associated pits with a certain kind of African-American culture. The media's job was to sell papers and magazines, and scary pit stories sold. But it wasn't all racism. The pits themselves changed, as backyard and inner-city breeders began breeding for large heads, for much larger sizes (instead of the 40 to 45 pounds of the Irish pits, we now see 95 lb dogs). Some people began intentionally trying to breed pits for human aggression, and some human aggression probably slipped in as an unintended consequence of breeding for large heads and large body size, which meant crossing pits with guarding breeds.
-Artificial selection actually is evolution in action. In wildlife ecology departments, we like to call it "experimental evolution", but it's certainly evolution. (This doesn't mean I agree with Karen Delise--I think pits are shaped very much by their evolutionary heritage, just as other dog breeds are. And I think people can really, really mess up a nice breed without even trying very hard.)
-Some people argue that 'normal' dogs don't exhibit violent aggression, so if pits sometimes do this, by definition they aren't normal. This doesn't make much more sense than arguing that normal dogs don't have hip dysplasia, so if labs and goldens do, they aren't normal dogs. Conspecific aggression that leads to fatal wounds is part of the evolutionary heritage of all dogs, just as prey aggression is. We hate to see it in our household pets, but it's important to realize that this is part of the normal evolutionary heritage of normal canids. Genes, however, are very labile things, and it's possible to select against certain traits and bring about changes in just a few generations, even in wild species (see the silver fox study cited yesterday). But genes are also very complicated things, and selecting against certain traits we like or don't like can often lead to sobering and unintended consequences (see English springer show gaits and aggression).
Sorry for such a long set of thoughts. As someone who loves pits but who understands that they do indeed have an increased potential to inflict serious wounds on other dogs, I think these thoughtful discussions are important if they lead people to more careful management. The risk of pits inflicting fatal wounds on children is vanishingly small, and I if we're going to bring human aggression into the argument, we need to recognize that pits were indeed long bred for low rates of human aggression, just as they were long bred for high rates of conspecific aggression. I personally certainly hope the two aren't connected, (so that we could breed for continued human-sociability while breeding against fighting) but I'm not sure there's any published evidence that shows us one way or the other.
And (name) and the others of you in Portland--Ed Russell and I will be presenting research on some of these questions (about evolution, epigenetics, and artificial selection) in Portland in March, and if you want to come argue with us, that's always fun at a conference.
Look beyond what your own eyes see