Why do animals have tails?

The tail is a flexible appendage at the rear end of an animal's body. The shape, size, structure and function of a tail varies from animal to animal.

We see many animals such as dogs, cats, birds, etc. in our day-to-day life with a tail but the question is why do these animals have tails? Is it just a structure that hangs on the rear end of the animal's body or does it serve an actual purpose?

The tail serves an actual purpose and it has a key role in the animal's life. The different roles that the tail plays are as follows:

FOR GRASPING

From left to right: Woolly monkey, Spider monkey, Howler monkey.

Some species of monkeys like spider monkeys, woolly monkeys, and howler monkeys possess a prehensile tail. The prehensile tail is strong and the animal can hang from tree branches just by its tail.

Other animals with a prehensile tail include opossum, pangolin and kinkajou.

FOR BALANCE

Kangaroo, otter and meerkat using their tail to maintain balance.

Several animals use their tails to maintain balance while moving on a narrow platform or jumping. Animals that use their tails for maintaining balance include cats, dogs, kangaroos, kangaroo rats, etc. Otters use their balance to maintain balance while standing on their hind legs. Meerkats' tail act as a tripod when they stand up on their hind legs and helps them maintain their balance,

FOR CHANGING DIRECTION

A cheetah using its tail as a counterbalance while changing direction.

The tails of many land animals and birds also act as a rudder and help them make a sudden change in direction while moving. For instance, predators such as cheetahs use their tails to change their directions quickly at high speeds when hunting. Birds use their tail as a rudder to change direction while flying.

BRUSHING AWAY INSECTS

Video Credit: Taryn Elliott

Animals use their tails to brush away flies and other insects.

LOCOMOTION

Video Credit: Ben Gibbs

Animals such as fishes, crocodiles, alligators, beavers, otters, and several others use their tails for locomotion(movement from one place to another). Fishes possess a caudal fin at their rear end which they along with the lateral flexion of the body use to propel themselves forward in the water. Crocodiles and Alligators also move their tails in a wavelike motion to propel themselves forward.

FOR DEFENCE & ATTACK

For some animals, tails can be the difference between life and death. Some animals use their tails to protect themselves from the attack of a predator.

Pangolin hiding its face under its tail while being curled up.

Pangolins hide their face under their tail as they curl up in response to an attack.

A representation of caudal autotomy in a lizard.

Several species of lizards and salamanders exhibit autotomy(the ability of an animal to shed or discard a part of its body) as a defence mechanism.

Lizards and salamanders lose their tails when attacked by a predator and getting separated, the tail wriggles for a few minutes which allows the lizard to escape by distracting the predator.

The scorpions of the genus Ananteris are also known to detach their tails from their body but unlike the tails of lizards and salamanders, it does not grow back.

The well-known stingrays also use their tails to defend themselves. Even though their primary mode of defence is swimming away from the danger, they can still attack when threatened or stepped on. Stingrays have a venomous, serrated sting at the end of their tails that they use to sting.

A scorpion using the stinger at the end of its tail to kill its prey.

Scorpions use the stinger on their tail to hunt their prey.

A northern death adder wriggling its tail//Video Source: YouTube

Some snake species exhibit caudal luring(waving or wriggling of the tail to attract prey). These snake species use their tails as bait.

COMMUNICATION

The tails of animals serve as a means of communication. They use their tails to express their feelings, mood and attract mates. The tail is also used to give warnings about the danger and to the danger.

Dogs and cats are examples of animals that use their tails to express their moods.

Peacocks use their tails to attract mates.

Deer and rabbits use their tail to signal other members of the group about a danger,

Rattlesnakes use the rattle present at the end of their tail to warn the predators.

FOOD STORAGE

The tail can be used to store fat. Animals such as the Gila monster and alligators use their tail to store fat and use it as an energy source when the food is scarce or unavailable.