Dogs have a sophisticated, nuanced and subtle language all of their own, composed of non-verbal signals sent using every inch of their bodies in different combinations. With time and practice, we can learn to read these signals and understand what our four-legged friends are feeling. This can help to anticipate what they will do in almost any situation, and can be extremely useful, especially in a bustlingly busy city like New York, where being able to gauge strange dogs accurately can be the difference between a nice walk and a bad experience for both you and your pet.
Although being fluent in doggy-language requires being able to read ALL of the signals they are sending as a coherent whole, let's begin by breaking the system down into its component parts:
A relaxed, happy dog's eyes will be their normal shape and size. When stressed or scared, however, dogs often widen or, conversely, squint their eyes. In addition, the direction of a dog's gaze can tell you a lot about how they're feeling: a very tense, direct stare is typically a sign of discomfort and a precursor to aggression, whereas a dog looking at you in a relaxed fashion, and giving long, slow blinks, can be an indication of contentment. Dogs will also choose to look away slowly when trying to defuse a tense situation, so if your dog does this it may mean they are uncomfortable with whatever is happening. Lastly there's a gaze known as "whale eye", which careful watching out of the corners of her eyes, thus exposing a lot of white, and is commonly seen when guarding a resource of some kind.
A relaxed, happy dog is likely to have a softly closed or slightly open mouth, possibly panting a little to cool down; when stressed or uncomfortable, she may have her mouth pulled back slightly at the corners and be yawning or licking her lips. Some dogs even show a submissive grin, with lips pulled up vertically and the front teeth exposed. Unfortunately this can be perceived as aggressive when in fact they're trying to show the exact opposite! To tell which is which, look for the other signals she's using - a submissive grin will usually be accompanied by submissive body posture like a lowered head, yelping or whining and squinty eyes. An aggressive snarl, on the other hand, will normally be accompanied by a wrinkled muzzle and the lips being pulled both up AND back, showing the back teeth as well as the front. Some dogs even display an aggressive pucker, with lips moved forward over teeth and air exhaled so their lips look puffy and large; this often goes hand in hand with a wrinkle forehead, and is the dog's way of saying "don't come any closer". Dogs may bite out of either aggression or fear, so learning to recognize these signs is invaluable to keeping you and your dog safe.
Of course, dog ears come in all shapes and sizes, which can alter the signals they send quite a lot. However, these are the basics to look out for: raised ears may indicate alertnes, with the ears typically turned towards whatever has caught her attention. However, aggression can also indicated by raised ears, so be sure to watch the rest of her body to tell what she's thinking. If she puts her ears back slightly, she is most likely feeling friendly, but if they are pulled all the way back flat, or sticking out the sides of her head, she may be feeling scared or insecure.
Just as with ears, dog breeds come with a variety of tail types: the pug's curls over her back, the greyhound's naturally tucks a little between her hind legs and Australian Shepherds are often born with naturally short little bobtails. It's important to bear in mind what your dog's tail looks like when she's relaxed, as this will be her neutral position. When happy, dogs will wag gently from side to side, or, if very enthusiastic, may more forcefully switch back and forth or round in circles. When feeling nervous or submissive, the tail may be held lower, tucked between the rear legs or even right up against the belly; bear in mind, however, that some dogs will wag when they're nervous or worked up - these wags will typically be more rapid and stiff, the tail held high. This again is where looking at the rest of your dogs' body will help you figure out what she is thinking and feeling.
Some dogs shed hair when stressed or scared (you may notice, for example, that after a vet exam the whole room seems to be covered in fur). A more recognizable symptom of strong emotion, however, is piloerection, also knowns as raising the hackles. This is comparable to a human getting goosebumps, and can mean that the dog is scared, aroused, insecure, angry, or even just wildly excited about something.
Typically a dog will use posture to make herself look either normal, smaller or larger.
When happy or content or playful, she will look her usual size (although in the latter she may bounce around a lot more, her other signals will all be relaxed and natural). When scared, dogs usually try to appear smaller by hunching over on themselves and possibly cowering low to the ground. They will typically lean away from whatever is scaring them or, if feeling a little braver, may approach tentatively with her weight poised on her hind legs to flee if necessary. A submissive dog will look very similar to a scared one, as she is trying to be as unthreatening as possible - she may have her head raised to greet the other person or dog, though. An assertive or aggressive dog will try, conversely, to look much bigger than she actually is. Her muscles will be tense and she'll stand erect (possibly even on tiptoe) with head and neck raised, and the weight centered either squarely on all four paws or slightly to the front, ready to move forward at a moment's notice.
As we can see from this, looking at any one feature of a dog's communication, while useful, does not actually give us the full picture. It's more like overhearing a few phrases than the full conversation, so in If Only They Could Talk: Understanding Your Dog's Language Part 2, we'll examine some of the many different combinations of signals and what they mean.