(b)
Have you ever heard that dogs and cats have the same ancestor? They have
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the same origin. The common ancestor is called "Miacis." It lived in the woods
about 45 to 65 million years ago. It is thought that it looked like a weasel. Miacis
lived in the woods, and some of them later started living in grassy fields. The
groups that stayed in the woods had a lot of places to hide, so they hunted
alone. They became cats. The groups that went into the fields didn't have places to
(c)²
13.
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(d)
hide, and hunted in groups. They became dogs. Animal's living place influenced its
development for a long time.
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