Tail

Function

Tails are also used for social signaling. Some deer species flash the white underside of their tails to warn other nearby deer of possible danger, and canids (including domestic dogs) indicate emotions through the positioning of their tails. Evolutionary pressures have led to the development of armored tails in some species, and some, such as the tails of scorpions contain venom.

Some species of lizard can detach ("cast") their tails from their bodies. This can help them to escape from predators, which are either distracted by the wriggling detached tail, or left with only the tail while the rest of the lizard flees. Tails cast in this manner generally grow back over time, though the replacement is typically darker in color than the original.

The tails of most birds end in long feathers called rectrices. These feathers are used as a rudder, helping the bird to steer and maneuver in flight; they also help the bird to balance while it is perched. In some species—such as birds of paradise and lyrebirds—modified tail feathers play an important role in courtship displays. The extra-stiff tail feathers of other species, including woodpeckers and woodcreepers, allow them to brace themselves firmly against tree trunks.

The tails of grazing animals, such as the horse is used both to sweep away insects, and positioned or moved in ways that indicate the animal's physical or emotional state.

Types

Human tails

Humans have a "tail bone" (the coccyx) attached to the pelvis, in the same place which other mammals have tails. The tail bone is formed of fused vertebrae, usually four, at the bottom of the vertebral column. It does not protrude externally, but retains an anatomical purpose: providing an attachment for muscles like the gluteus maximus.

Gallery

See also

References