Mammals have several traits in common, including the presence of hair or fur, sweat glands, and mammary glands. Some mammals, such as dolphins and whales, evolved to live back in the ocean by adapting from land-dwelling creatures.
CK-12 (Middle School)
What distinguishes mammals from other vertebrates and from each other?
RST.2 - Main Ideas
DEPTH OF KNOWLEDGE (DOK) LEVELS:
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