Exoskeleton

What is an Exoskeleton?

An exoskeleton is a hard shell on the outside of some animals. It helps keep their shape and protects them, just like a suit of armor. Unlike humans, who have bones inside, these animals wear their bones on the outside!

Many insects like beetles and butterflies have exoskeletons. So do crustaceans such as crabs and lobsters. Even tiny creatures called tardigrades, also known as water bears, have exoskeletons to stay safe.

How Do Exoskeletons Help Animals?

Exoskeletons help animals in many ways. They give support, protect important parts inside, and help with moving and finding food. They also let animals show off to find friends or mates. The hard shell keeps animals safe from harm and pests, and it gives places for muscles to connect.

Some animals, like turtles, have both an inner skeleton and an outer shell for extra protection. Other sea creatures, including snails and clams, also have hard outer shells that act like exoskeletons.

Growing Up with an Exoskeleton

Because an exoskeleton is hard, it cannot grow as the animal grows. So, animals with exoskeletons must shed their old shell when they get bigger. This process is called moulting. When it's time to shed, the animal makes a new, soft exoskeleton under the old one. After shedding the old shell, the new one is soft at first and can still grow a little before it hardens. During this time, the animal usually hides to stay safe until its new shell is ready.