Transcription: Although most of the animals with which you are familiar are vertebrates, the majority of animals in creation are invertebrates. This jellyfish, for example, is an invertebrate. Now remember, invertebrates do not have endoskeletons. This jellyfish doesn't have an endoskeleton because it doesn't need one. The water in which it floats supports it. Now not all invertebrates can float in the water like the jellyfish. These crabs, for example, are invertebrates, but they're clearly not floating in the water. They clearly have some kind of support. A crab's support comes from its exoskeleton. Some p ...
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