Dog aggression. That's the topic of this lecture, and specifically dog aggression towards humans. It's a big problem that we face. And as we have dogs become a bigger part of our lives, not just living outside of our houses, but sleeping in our beds, it's something that we have to address. And that's what this lecture is about, is what do we know so far about dog aggression, and what does breed tell us, or communicate about dog aggression. In the book, it's going to be Chapter 9 that is most relevant, and, of course, Dognition is collecting data relevant to dog aggression as well. So look out for our releases on that topic. So dog aggression happens. Dogs, even though they've been selected to be interested and friendly towards us, there's tremendous individual variability in dogs' tendency to be aggressive and also the context in which they show aggression. Interestingly enough, this photo was taken during a play bout. That's actually my dog [LAUGH] playing with a friend. And while this looks terrifying, that this person is about to get mauled, actually my dog was just playing here. But playing in a very rough way that, you know, tended to suggest that probably we needed to not play this way with this dog, because it seemed to be that the dog couldn't be trusted to not hurt somebody potentially during these types of play bouts, just because of how rough he got during play. So there's all sorts of dog aggression. There is the aggression that you think of that's in the newspaper, but then there's also these types that are just an accident and where we need to just set boundaries and realize that dogs, even though they're domesticated, they are still animals and they can hurt us even though they don't mean to and that different individuals are going to need different strategies. And that's part of, just like with your kids, you have to have recognition that one dog may need one strategy while another needs a different type of strategy, so that they're happy and don't hurt anybody, because that would be horrible for them as well as the person that they potentially hurt. Okay. So dog bites in the US, it's a serious problem. Almost five million people, it's estimated, are bitten by dogs in the US every year. That is a lot of dog bites. I mean, you'd think, why do we even keep dogs at all with that many bites. But I think if you think about the fact, if everybody had a pet wolf, you know, I can assure you that that number would be a lot higher. So, you know, it is still amazing that dogs are able to be as good as they are, but that is still a very high level of bites. About 30,000 people require reconstructive surgery every year, and that's even more horrific of a number. And finally, half of the children in the United States have been bitten by the age of 12, which is terrible if you're a dog lover. You want kids to have a wonderful experience with dogs. You don't want people being bitten by dogs. And if you are a dog lover and you're somebody who cares about dogs, you have to be cognizant of the fact that the person who you're meeting who may not be as friendly towards dogs, there might be a reason. They might have had a really bad experience with dogs, and a lot of people have had that bad experience. So we need to be sensitive as we're taking our dogs around in the community to the fact that just because somebody's not excited when you walk up to them with their dog, it may not be just they're not, you know, an animal person, it may be that they really have had a bad experience with dogs in the past. So who's responsible for all this aggression? Well, I think if you were to go and read the legal code in many states and counties in the United States, there would be a very simple response. It's this guy, the pit bull. There is a breed that is responsible for most dog aggression. If we just could get this breed to behave or people to not keep this breed anymore, we're not gonna have a problem with dog aggression anymore. And, unfortunately, I don't think that the solution is that simple. Unfortunately, for pit bulls, I do not think that they are the culprit. They, and this is based on the scientific literature, not on any bias I might have for pit bulls. And one of the reasons that pit bulls have sort of cropped up as sort of the favorite breed to pin dog aggression on towards people is the fact that there is this idea that pit bulls somehow are different, that they have a bite force that is ridiculously strong. People are often citing an 18,000-pounds-per, sorry, 1800-pounds-per-square-inch figure. And you have to wonder, where do figures like that come from and how do we really know it's pit bulls that are making all the problems? I mean, how good is the data to pin something on a certain breed? And the answer is, the data's not good at all. Many scientific papers that have cited the figure that pit bulls are able to bite at 1800 pounds per inch are citing a paper that was published in 1984. And in that paper, it says pit bulls bite with greater force than most dogs, and they cite the number 1800 pounds per square inch. But when you go to the paper that Baack, et al., cite as saying that pit bulls bite in that way and with that level of force, Boenning, et al., published in 1983 or the year before, there's actually nothing in the entire paper, go look at it yourself, that suggests that pit bulls have a bite force of any magnitude. So, for some reason, people started talking and believing about pit bulls having this magical bite force, but there really is no data to suggest that they're different. So what about the fact that pit bulls are somehow the main culprits here, that it's really just specific to a breed that this level of aggression occurs?