10 things we didn't know last week
16:59 UK time, Friday, 23 March 2012
1. It rains liquid methane once every 1,000 years on Titan, the largest moon orbiting Saturn.
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2. Barack Obama knows sign language.
More details (Storyful)
3. Holding a gun makes you more likely to think other objects are guns.
More details (Chicago Tribune)
4. The Welsh language can be confused with Hebrew.
More details (The Independent)
5. Female animals can have ovaries on the outside.
More details (New Scientist)
6. Noise stunts the growth of plants.
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7. Listening to opera helps mice recover from heart surgery.
More details (New Scientist)
8. A cat can fall 19 storeys and survive.
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9. Birds take "girls only" holidays.
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10. The UK is the world's third-largest purchaser of human hair.
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