Active and passive submission are behaviors that dogs exhibit to communicate their social relationships, particularly their acknowledgment of another's dominance or authority. Here's how they differ:

1. Active Submission: This type of submission is more energetic and engaging. When a dog shows active submission, it may perform behaviors like licking the face of the dominant individual (which is a behavior rooted in puppyhood, where pups lick the faces of adult dogs to encourage them to regurgitate food). Actively submissive dogs might also wag their tail, crouch, lower their ears, avert their gaze, or offer a paw. These behaviors are trying to communicate respect, acknowledgment of the other's higher status, or to appease the other dog to avoid any conflict.
2. Passive Submission: This is exhibited when a dog takes a more subdued approach. In passive submission, the dog might lie down with its belly exposed and might remain very still. By exposing its vulnerable areas, the dog shows that it trusts the dominant individual and acknowledges their authority. This behavior is also intended to stop any aggression from a dominant dog, as it signals that they are not a threat or challenge.

Both forms of submission help maintain peace and establish clear hierarchies within groups of dogs, reducing the chances of conflict escalating. Understanding these cues in dogs can help humans interpret their interactions more effectively and respond appropriately.