Page 26 - 新思维科学学生用书4 样章

1.4 Different kinds of skeletons

Identification keys

Scientists use identification keys to help them sort and identify

objects, materials and living things. Identification keys are

based on questions that can be answered either ‘yes’ or ‘no’. By

answering the questions, we can identify and name animals, or sort
them into the right groups.

Look at this example which identifies different types of vertebrates.

Types of vertebrates

Does the animal have fur?

yes no
Does the animal
It is a mammal.
have feathers?

yes no

Does the animal have
It is a bird.
a smooth, wet skin?

A panda is a mammal.
yes no

Does the animal have
It is an amphibian.
a dry, scaly skin?
A pigeon is a bird.

yes no

A frog is an amphibian. It is a reptile. It is a fish.

A lizard is a reptile. A carp is a fish.

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