| Before I show you how to classify animals, make sure you remember
how to classify all living
things. |
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To classify an animal, first the scientist
will look to see if the animal has a backbone.
- Vertebrates are animals with backbones. Examples of vertebrates
are fish, humans, birds and snakes.
- Vertebrates are categorized into 5 major groups:
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- Invertebrates are animals that don't have backbones. About
97% of all animal species are invertebrates.
- There are eight phylums of invertebrates:
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- After deciding whether or not a backbone is present, a scientist will
look at the animal's symmetry:
- Asymmetrical animals (most sponges) have no general body
plan or point of symmetry that divides the body into mirror-image
halves.
- Radially symmetrical animals (such as anemones and sea
stars) have body parts organized around a central point and tend
to be cylindrical in shape.
- Bilaterally symmetrical animals (such as humans and fish)
have their body parts arranged the same way on both sides.
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