Invertebrates are animals without a backbone. That means that they are the opposite of vertebrate animals. Invertebrates make up 95% if the Earth’s animals! Some invertebrates have a hard covering on the outside of their bodies called an exoskeleton. Besides that, invertebrates are usually creatures that do not have bones as a support. Invertebrates are cold-blooded, which means they adjust their body temperatures to the temperature of the environment. Examples of invertebrates are spiders, sponges, squids, crabs, snails, or clams! Most invertebrate animals are small because they need a strong backbone to hold up big bodies. Since invertebrates don’t have backbones, they are usually much smaller than vertebrate animals.