The most important thing to a wolf are his/her fangs. For an otter it's his/her tail. Tigers mark of excellence are their stripes. For the malamute/husky crowd, it's necessary to have a well-curled tail.

In addition to looking cute (and saying I'm soft, stroke me), braniff's tail provides that all important yaw-control*

*It's an airplane joke, ask a pilot if you don't get it.