Reason Know why do dogs wag their tails?

Why do dogs wag their tails? Most dogs wag their tails at some point or another in order to communicate with people and other animals. The behavior is often seen as a sign of friendliness or trust, and it can be very calming for both the dog and its handler. While there are many theories about why dogs wag their tails, the most likely explanation is that it serves as a way to keep cool and stay warm in hot weather.