An invertebrate is an animal without a backbone.
Invertebrates are a very diverse group of species, including:
- Crustaceans (lobsters and crabs)
- Mollusks (squids, snails and clams)
Characteristics common among invertebrates:
- All of them lack a backbone
2. These soft bodied animals maintain their body shape by maintaining their internal pressure. Some invertebrates have hard outer covering called as exoskeleton to protect them from their predators.
3. The body of the invertebrates is of two types. They are radial symmetry (no left or right sides) and the other one is called as bilateral symmetry. (Can be divided in one plane into two mirror-image halves)
4. Habitat: The invertebrates are generally found every where in air, water and soil.
5. Shape: The invertebrates are various in shape. Some do not have any regular shape like amoeba. It changes its shape. The rest of the invertebrate have some definite shape. Some of them are like plant appearance,ribbon-like, vermiform and star.