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

Míklósi, Ádám (2007). Dog behaviour, evolution, and cognition. Oxford: Oxford University Press. ISBN 978-0-19-929585-2.

[1] Míklósi, Ádám (2007). Dog behaviour, evolution, and cognition. Oxford: Oxford University Press. ISBN 978-0-19-929585-2.

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