Get ready for an all too common scene, but remember to withhold judgement about what's going on. What body language do you see?
Large dog-
Face: ears slightly back, possibly slightly pulled up towards each other, mouth closed
Head: lowered and facing the smaller dog
Tail: raised, not wagging
Body: slightly curved, posture maybe slightly leaned back with one hind leg behind the other rather than square
Small dog-
Face: ears low and back, eyes wide with eyebrows slightly raised, mouth tense and closed
Head: raised normally, but indirectly looking at the large dog
Tail: unknown from this angle
Body: this dog's body seems quite stiff, one leg raised to hold close to their body (vs raising to touch/smack paw at the other dog), possibly leaning slightly away from the larger dog
Context: outdoors, but door to the inside is open.
Okay, you've read through the body parts synopsis. Did it match what you saw? Did you see anything else?
Background-
This photo was provided by a colleague who took in an adolescent foster dog.
Interpretation-
The little dog here is showing multiple signs of discomfort or fear. Who can blame her, as a comparatively easy to hurt little dog who's personal space is being invaded without consent by a much larger, physically fit, unfamiliar and somewhat intense adolescent male?
The following picture is what came next. Did you see it coming?
Her more subtle body language clearly signals that she desires space. When it's ignored, she escalates slightly to clarify, showing teeth in a snarl and turning her head ever so slightly towards him. "You need to back up now." We can see his posture gets even more stiff, raised and even leaning in a bit more. Oh, teenage boys. This does not mean there's some sort of dominance struggle going on, but it does mean this dude needs to work on his social skills.
Although this is a nice demonstration of what trainers mean by "ladder of aggression," in which social cues are escalated if ignored, this behavior is completely normal and should be expected in this context. A dog communicating personal boundaries and even defending their personal space after plenty of warning should never be scolded or punished. Not only would doing so be unfair, ineffective and unnecessary, but what would the goal be in doing so? It isn't beneficial for a tiny dog to recklessly accept being crowded or pushed around by a much larger and overly excited dog. They could get hurt! Even if by accident.
The next time you see a dog snarl or snap, consider the communication and body language cues that led to that point. Quick and occasional arguments are nothing to fear, but if this happens regularly, consider how you may advocate for or adjust your responses in order to meet your dog's needs.
Thank you to Nathalie Smith for this excellent photo sequence!