Adopted dog can't stop wagging her tail - she's so happy. Happy dogs show enthusiasm by rapidly wagging a low, untucked tail, sometimes so intensely that their entire rear end sways.
A tucked or cocked tail signals insecurity or fear. Other signals are also important when assessing mood, such as ear position, facial expressions and weight distribution. You can find even more exciting animal topics in the free partner newsletter from Landtiere.de, which you can subscribe to right here.