You might have seen a wall lizard escaping by leaving behind some portion of its tail when chased. This trick is used by the wall lizard to escape from attacking enemies. The detached tail keeps wagging for some time. This distracts the attention of the enemy and the lizard escapes by confusing the enemy. The process of detaching a portion of tail is known as autotomy.
The bones in the tail of a wall lizard are joined together loosely and it can detach a portion of the tail easily at its will. Any portion of the tail separates easily from the main body. The ends of blood vessels are almost sealed so it does not lose much blood. So it is easy to release a portion of the tail without blood loss. Also a new tail grows without much delay.
Lizards are a group of reptiles. Most of them are harmless to human. Researchers have conducted studies over more than 6000 species of lizards till today. Lizards are found mostly in tropical countries. Normally, their bodies are divided into three separate parts, head, trunk and tail. Almost all varieties have four legs. Most of the lizards are hatched from egg, but some of them are born directly. Main food is insects. There are varieties with more than 3 meters in length and they are really frightening in sight. Their tail is a strong weapon for them to attack their enemies. They can easily kill a fairly large animal with one blow of their long and strong tail. Lizards can run, swim or even glide through the air.
There are certain other animals too that can get rid of their legs. Crabs and lobsters come under this category. When a fish catches the leg of a lobster, it jerks away its leg and escape. These are defense mechanisms present in some animals that enable them to survive.