Invertibrates

If we and the rest of the backboned animals were to disappear overnight, the rest of the world would get on pretty well. But if the invertebrates were to disappear, the world's ecosystems would collapse.

Invertebrates animals are the animals which do not have the backbone or vertebral column are called invertebral column. Tapeworm, sponge, hydra, butterfly, spider, and etc. are some invertebrates. Invertebrates have not backbone. It may be unicellular or multicellular. Amoeba, paramecium, and euglena are some unicellular invertebrates whereas an earthworm, crab, cockroach, hydra, and butterfly are some multicellular invertebrates. Most of the invertebrates have soft body due to the absence of backbone. however, the body of some animals like a snail, crab, and the beetle is covered with a hard protective cover BUt this cover is not a vertebral column.
Invertebrates live in water and on land. Invertebrates like paramecium, sponge, hydra, crayfish, crab, and starfish are found in water. Similarly, Invertebrates like earthworm, grasshopper, honeybee, and snail are found in the land. They have a less developed body. Some of the invertebrates like tapeworm, liver fluke, roundworm, leech and mosquito lives as parasites.
Image source: Google