Ear tuft

Ear tufts are not found on all cat breeds.

[1] Bird ear tufts are skin projections covered in feathers found in some bird species, most notably various species of owl, vaguely resembling mammalian ears, but unrelated to the animal's hearing.

Theories about their function range from improved ability to camouflage,[2] aiding in finding a suitable mate,[3][4] to giving a more threatening appearance to discourage predators.

[5] In the Araucana chicken breed, ear tufts are a mutation.

It causes a skin projection covered in feathers to appear on the sides of the head near the ears.