Why do so many animals have tails?
The answer is 'natural selection"—it might sound easy to guess, but it's entirely accurate.
They assist various types of animals, including insects, fish, lizards, mammals, etc., in surviving long enough in the wild to reproduce.
Animals with tails have evolved structures and behaviors to maximize the use of this part of the body.
For example, an insect's tail can serve as a stinger, a place to store venom, a compartment for eggs, and help maintain balance while flying, among many other uses
In vertebrates, the tail is primarily used for locomotion and balance. For example, the tails of fish and crocodiles sweep back and forth, propelling them easily through the water.
The tail also serves as an energy reserve and is a "disposable" part.
Skinks and many other lizards can voluntarily cut off their tails when bitten by a predator, and their bodies will then regenerate new ones
Giant sauropods (which walked on all fours) had long tails to balance the weight of their extra-long necks.
At the same time, the birds' tails work with their wings to prevent them from falling from the sky. The colorful tail feathers of male birds of paradise, turkeys, peacocks, and several other birds help them attract females.
Many mammals, such as squirrels and some monkeys, use their tails as limbs to move between branches.
Why don't humans have tails like dogs, cats, monkeys, or the vibrant feathered tails of peacocks, even though our ancestors once possessed them?
Scientists believe that these tails disappeared from our human ancestors approximately 20 million years ago as they transitioned to walking upright, rendering the need for tails to assist in balance obsolete.