Sickle tail

The sickle tail is the single phenotypic characteristic that seems to separate dogs from wolves[1]. Dogs who have tails tend to have an upward curve in the tail, which is called the sickle tail. Wolves' tails, on the other hand, hang straight; this is called the brush tail—similar to that of a fox.

References

  1. ^ Míklósi, Ádám (2007). Dog behaviour, evolution, and cognition. Oxford: Oxford University Press. ISBN 9780199295852.