The reasons why dogs will lie down first when they see the same kind of dogs:

1. This kind of behavior of dogs is a sign of liking and respecting the same kind of dogs, which means that the dogs are docile and kind-hearted. Dogs will not easily quarrel with their own kind, and can get along well with their own kind and become good friends.

2. When a dog sees another dog, a posture like crawling and raising its buttocks may be a request gesture by the dog to invite the other dog to play. This is telling strange friends "I am not aggressive"

3. This behavior is a very relaxing way. This is a common body language used by dogs to communicate.