Top 10: Which animals sleep the most?

(hours spent sleeping per 24 hours)

1. Koala: 20-22

2. Sloth: 20

3. Brown bat: 19.9

4. Giant armadillo: 18.1

5. Python: 18

5. North American opossum: 18

7. Owl monkey: 17

8. Human infant: 16

9. Tiger: 15.8

9. Tree shrew: 15.8

Read more:

• Top 10: Which animals have the strongest bite?
• Top 10: Earth's smallest mammals

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