To understand what dogs are telling us, we have to observe and interpret their body language. Unfortunately, it doesn’t always translate. Sometimes what people think are friendly gestures can actually be signs of aggression, stress or fear. Misinterpreting what a dog is saying can have consequences for your safety, so it’s important to know what his body language actually means. From tail wagging to smiling, here are four common behaviors that are easy to misread.  

Tail Wagging

Tail Wagging

When you see a dog wagging his tail back and forth, don’t assume it’s a sign of friendliness. A tail wag is an indication that a dog is willing to interact, but it could be either a friendly or aggressive gesture. To interpret what a tail wag means, look at the rest of the dog’s body and posture. If his ears are pinned back, it likely means he’s uncomfortable or stressed and would prefer to escape your attention. But if the dog is being friendly, he may come over to you or show his side or hindquarters to be scratched. He also may lean up against you or nudge your hand to get attention.
Showing His Belly

Showing His Belly

Just because a dog is lying on his back with his belly in the air, it doesn’t necessarily mean he wants you to give him a belly rub. For a dog, lying belly up can be a sign of utter submission. It’s his way of saying, “I come in peace and am not a threat.” Some dogs do show their bellies to get attention and will gladly accept belly rubs. But others may feel threatened by a human standing over them in such a vulnerable position. A dog in this manner may be trying to say, “I need space.” If a dog is on his back and you want to pet him, ask him to sit up first. That way, you can avoid making him feel uncomfortable. If you hear a dog snarl or growl when he’s on back, he’s saying, "Stay away" — you should listen to him.
Smiling

Smiling

Some people recognize a dog as smiling when he’s panting with his mouth open and has a relaxed expression on his face. But for other people, a dog smile is when a pup approaches them and shows his teeth before getting a treat or attention. The first scenario described usually indicates that the dog is happy, but the second one is a little trickier. Humans are one of the only species who bare their teeth to show happiness. For most animals, baring teeth is considered a threat. With that in consideration, the smile in the second scenario could indicate a submissive grin, which is a gesture of deference. Or it could be a snarl, which is a sign of aggression. In a snarl, the nose usually becomes wrinkled and the canine teeth are exposed. Plus, the dog’s facial expressions and posture are usually stiff. Never approach a snarling dog.
Raised Hackles

Raised Hackles

Dogs usually raise their hackles (also called piloerection) when they feel wary or cautious. But this is not always a sign that a dog is about to attack another dog. Sometimes a dog may have his hackles — the hair on his neck and back — raised as he greets another dog and then go into a play bow. How confusing! If your dog has raised hackles, be cautious — especially if he also has an unfriendly expression like the dog in this photo. Vocalization also may or may not accompany raised hackles and is another indicator of arousal. Consider waiting until he calms down before you let him interact with other dogs. If he’s in a state of high emotional arousal, give him space and let him relax.

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