Signs of confidence: erect stance (standing tall), tail up, tail wagging in a slower sweep, ears pricked up or relaxed, direct look; relaxed, smaller pupils.
Signs of fear or concern: lowered stance, tail down or tucked under, tail wagging in a quick, frantic buzz; looking away or turning head away to look so that whites of eyes show ("whale eye"); dilated pupils. Dogs often bark out of fear, in an attempt to keep a distance between themselves and the Big Scary Thing, especially if they are cornered, fenced in, or on a leash.
Dogs that are aroused will often have their hair stand on end, usually the "hackles," the areas over the shoulders and just before the tail. This doesn't necessarily mean aggression, just that they are on high alert. Some dogs get "raised hackles" more easily than others; it's like some people who get red in the face very easily
This pup is unsure about the plastic ducky
(and maybe the water, too). Notice most of
her body is still on shore while she
stretches her neck out to sniff.
She's not fearful, just uncertain.
Dominant body postures: Standing over another dog, standing tall, hooking the dominant dog's chin or paw over another dog's shoulders, calmly accepting other dogs licking at their lips; staring. Some confident, dominant dogs will roll on their backs, exposing their bellies, in an attempt to reassure a more shy or submissive dog, or to get that other dog to play. They will be relaxed when they do that, and usually still look the other dog in the eye. Sometimes mounting ("humping") another dog is a sign of dominance, but not always; this often-misunderstood gesture can also be used by a lower-ranking dog to try to demonstrate his allegiance with a higher-ranking animal.
Submissive body postures: lowered head and body; allowing other dogs to stand over them or hook their heads over their shoulders; licking at other dogs' lips and mouth corners; looking away from the other dog; rolling on back and craning head away from other dog, while covering tucking their tail.Play time:Dog play is often initiated by a play invitation like a play bow or pawing the air. Even when dogs play very roughly, they are usually fairly relaxed; their lips usually cover their teeth (not drawn back in a snarl). Dogs often bark in play; this will usually be higher-pitched than that same dog's fear-bark or warning-bark. Sometimes dogs will mount each other in play. They are often excited, but not in a sexual way, and it seems to be a way to bond. It is occasionally a show of dominance, but not always. Some dogs appear to mount high-ranking dogs in an attempt to find their place in a group that is much more complicated than a straight-line hierarchy.
Dogs can feel stressed in situations of frustration or fear (including during class or learning a new task). Look for clusters of stress signs: Shaking, whining, "submissive" urination, ears back, pupils dilated; rapid panting with corner of mouth pulled back; tail down; body lowered; sweating through paw pads, scratching at self; sudden interest in sniffing; yawning; blinking eyes; licking of lips or nose, or stretching tongue forward; looking away or turning head away; shaking body. Frustrated dogs often bark (this is especially seen in "fence fighting", when two dogs on opposite sides of a fence bark at each other; another easily-observed example is dogs in a shelter watching other dogs walking by; dogs that must pass each other on-leash often bark in frustration).
Also, dogs, as pack animals, have highly-developed ways of avoiding and diffusing conflict and aggression. Dogs therefore use "Calming Signals" to reduce stress for themselves and others they interact with (including humans). Calming signals include: Yawning, looking away, lip-licking, moving slowly, circling, sniffing the ground, becoming "distracted", sitting or lying down. Some of them are also the "appeasement display" behaviors that are developed to turn away aggression and threats of aggression - these are often confused with "the guilty look" that dogs may appear to be giving when scolded for doing something. Note that most of these are the opposite language from the directed attention that would be found in an aggressive interaction.
Signs of aggression include: Stiff legs and body; growls, lowered head; ears "pinned" back close to the head; eyes narrow and fixed intently; lips sometimes drawn back in a snarl; "hackles" (hair along back, especially over the shoulders and rump) up and erect; tail straight out, and intense stares (pupils may be fully dilated or shut!).
