A short but good read, with some great photographs. The basic premise is that dogs are naturally social, cooperative animals who want to live in social harmony with fellow dogs (and/or with their human "pack"). Dogs have developed a nuanced language for communicating that they are friendly and nonthreatening. These "calming signals" (Rugaas's term) are typically used as preventative measures (dogs use them when greeting or passing each other to prevent conflict from breaking out) or as deescalation tactics, to calm down a situation that is getting tense or uncomfortable. Calming signals are a way of communicating the dog's intention to others, but they also seem to be self-soothing techniques that help the dog calm their own nervous system.
Some calming signals seem to be inborn (Rugaas notes that puppies begin using yawning as a calming signal within a few hours of birth) but others are learned or honed through extensive social contact with other dogs. This is a big part of why early socialization is so critical for puppies, because meeting lots of other dogs (esp mature, emotionally well-adjusted dogs) helps them collect lots of social 'data' on canine communication techniques. Puppies who are raised by their mothers (or who receive a lot of early, positive socialization experiences) tend to grow up to become much calmer, more well-adjusted dogs.
Dogs can "lose" this form of language if they aren't properly socialized, or if they are punished by humans for using these signals. Unfortunately, humans typically don't know how to read calming signals. People will often misinterpret certain signs (such as sniffing the ground, looking away, or moving in a curving line instead of coming straight back to us) as defiance, when in fact what's happening is that the dog senses the human's anger, feels uncomfortable and worried, and is trying to use calming signals to defuse tension or to communicate that they mean no harm. (This made me so sad!!! On the trail and in my agility class, I often see people yelling at their dogs or scolding them for doing many of the behaviors described in this book. And I have often been guilty of interpreting Pip sniffing the ground or turning his back to me as him deliberately ignoring me, when actually it sounds like he's responding to the frustration in my body language or voice.)
One thing I found super interesting: Rugaas has found that humans can actually use calming signals too, and dogs will be able to "read" them.
Here are some of the most common calming signals:
1. Turning head to the side. Making direct eye contact is impolite and might even be perceived as threatening. Dogs will turn their head to the side when meeting to calm the other dog and assure them that their intentions are good. (This signal may also express that they are uncomfortable and are wanting to calm down a potentially tense interaction.) When dogs do make direct eye contact, they use a relaxed gaze, letting the eyelids droop and the eyes go soft. Apparently the direct eye contact thing is why dogs don't like to look directly at a camera! This calming signal is one that humans can use too. (I actually found this really interesting because so many people train a "look at me" signal where the dog is expected to maintain direct, unblinking eye contact. If that is actually really uncomfortable for the dog, I wonder if there's an alternate attention behavior that could be trained instead?)
2. Licking their lips. Dogs do this to express that they're feeling a little uncomfortable or worried. They might use it if someone is hugging them too tightly or if they're in an unfamiliar environment and are feeling on edge. Licking is a way of communicating that discomfort while also calming themselves down. Humans can lick their lips too as a calming signal.
3. Yawning! Apparently this is a great one for humans to do with dogs. If you are meeting a new dog who seems a little skittish or on edge, you can do big, relaxed yawns repeatedly while averting or softening your gaze to show that you're not a threat. Other people can yawn when they meet your dog too to make them feel more comfortable.
4. Splitting up. If two dogs are getting rowdy or are having a face-off that seems tense, often another dog will come over to split things up. The third dog is basically saying, "hey guys, chill out, let's take a breather," and they're also positioning themselves so that they can intervene if they need to. Older dogs will often do this instinctively to protect puppies or smaller dogs. You can do this for your dog by calmly putting yourself between them and something that is making them uncomfortable (another dog, a person, the source of a scary noise, etc.). It just helps the dog feel more secure.
5. Turning to the side or turning one's back to someone else. (I've definitely seen puppies and young dogs do this while playing -- when things are getting too wild, they'll start backing into each other or turning halfway to the side, as a way of deescalating the intensity of play.) You can also turn your back to your dog or turn to the side as a calming signal -- this can help puppies calm down and stop jumping.
6. Sniffing. This one was so interesting! I've often noticed that when Pip sees another dog from a distance while we're out on a walk, he will immediately veer off to the side and begin sniffing at the grass. I always thought that he was checking to see if the dog had marked there (which wouldn't really make sense, bc often the dog is approaching us head on?) but it turns out that this is actually him communicating across a distance to the other dog. Sniffing the ground, turning slightly to the side, and curving as he approaches the other dog on the sidewalk are all ways that he communicates he's not a threat.
7. Lying down/lying still. Pip also does this one -- when he's off leash, if he sees another dog in the clearing or further up the trail, he will lie down in the grass and wait for them to approach. Then (apparently once he's received a calming signal from the other dog) he'll spring up and run towards them in a curving line to play. If dogs are closer to each other and sense that the other dog is a little uncomfortable, they'll also sometimes drop down and lie still for as long as it takes the other dog to start showing more positive/less tense body language.
8. Moving slowly. Apparently you should never run at your dog (and you should generally try to avoid moving towards them in a straight line, with outstretched grabby hands). Dogs will often begin moving very, very slowly as they approach a new dog or person, which is a way of communicating that they're not going to attack.
I also learned that it can actually be scary for your dog to be kept on a too-tight leash when they are encountering an unfamiliar dog or person. This is because they don't have enough room to perform the appropriate calming signals, so they can't communicate to the new dog that they are nonthreatening or adequately read/receive calming signals from the other dog. You also shouldn't drag your dog into meeting another dog, or pull them forward if they are reluctant to move past the other dog on the sidewalk. Not only is this physically painful and unpleasant for the dog, it also forces them to perform a lot of behaviors that stress them out (and might read as threatening to the other dog), like moving quickly forward in a straight line, without being able to turn their head or body to the side.
This book was recommended in Jane Killion's When Pigs Fly: Training Success with Impossible Dogs, which I finished last night and cannot praise highly enough!!