Invertebrates are animals with no backbones. Other than that, different kinds of invertebrates do not have much in common.
There are many kinds of animals with no backbones. Some have soft bodies like earthworms or jellyfish. Some have shells on the inside like the octopus. Others, like clams and snails, have a hard shell on the outside.
Some invertebrates are very small. They can only be seen with a microscope. Some are huge. The giant squid can be 59 feet long.
Most invertebrates are arthropods. That means they have their skeletons on the outside of their bodies. Insects and spiders are in this group. Lobsters and crabs are in this group, too.
Almost all of the animal species in the world are invertebrates. And they have been around a long time! Fossils from 600 million years ago have been found. Worm tracks have been found from almost a billion years ago.
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APA Style: What is an Invertebrate?. (2020, November). Retrieved from Facts4Me at https://www.facts4me.com
MLA Style: "What is an Invertebrate?." Facts4Me. Nov. 2020. https://www.facts4me.com.