Invertebrates are animals that do not have any backbones; they also have features unique to the specific species.
The species of invertebrates include jellyfish, lobsters, crabs, clams, sea stars, sea urchins, sponges, insects, spiders, worms, centipedes, and millipedes. Invertebrates and vertebrates share features like hemoglobin which makes your blood cells red, poison defense moves, strong eye vision, and gills. However, one feature that vertebrates don’t have but invertebrates do is called radial symmetry.
Other types of invertebrates are coral, which has cells that can sting you, and the sea anemone, which uses its tentacles to sting. The invertebrates that have armored shells and spines are called echinoderms. Other types of invertebrates are called arthropods and can be distinguished by a hard covering over their bodies called an exoskeleton. Bugs that are arthropods are spiders, insects, centipedes, millipedes, and the crustaceans like lobsters and crabs. More than 90 percent of animals in the world are invertebrates.
All invertebrates are known as simple animals. Invertebrates are the most common and unique animals in the world because of their abilities and how they hold good mechanisms.
[Source: Encyclopedia Britannica Animals]