5. The “whale eye” is another clue that a dog is feeling anxious, defensive, or simply stressed. “Whale eye” occurs when the white portion of the eye (sclera) is showing in his profile, at the corner or rim of the eye.
6. A relaxed dog typically has a closed, relaxed mouth, or a slightly open mouth. A dog that is scared or submissive may have his lips pulled back slightly in the corners. Or he might flick his tongue in and out, or lick whoever he’s interacting with. Some dogs display a submissive grin by pulling up their lips vertically and showing their front teeth, along with a submissive body posture.
7. A submissive grin differs from bearing teeth as an aggressive display. Usually an aggressive dog retracts his lips vertically to display his front teeth while also wrinkling his muzzle. Body language will help confirm whether the dog is submissive or aggressive.
8. Exaggerated yawning, not following a nap, can often indicate stress. Another possible indication of stress is scratching around the collar. Fleas are not always to blame.
9. When a dog is relaxed, he’ll hold his ears naturally. An aggressive dog may raise his ears up and forward. If a dog has his ears pulled back slightly, he’s probably sending a friendly vibe. If his ears are completely flat or straight out to the sides of his head, he may be scared or submissive.
10. A wagging tail doesn’t necessarily mean a dog is friendly, contrary to popular belief. Dogs may also wag their tails when they’re feeling aggressive. If they’re defending their ground, they may hold their tail high and rigid, and move it stiffly back and forth. If they’re nervous or feeling submissive, they might lower their tail or tuck it under their rear legs.