10 things we didn't know last week
1. Piranhas bark.
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2. Brunettes make better friends.
3. Self-made millionaires are more likely to have gone to state school.
4. One in six mobile phones in Britain is contaminated with poo.
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5. Penguins rescued from oil slicks get knitted jumpers to keep them warm.
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6. There will be more people in the Millennium Stadium in Cardiff on Saturday to watch the Wales v France World Cup semi-final on video screens than there will be at the actual match in New Zealand.
7. Meerkats recognise each others' voices.
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8. Lady Gaga doesn't like Lady Goo Goo.
9. Babies know if someone is being unfairly treated at just 15 months.
10. Really good sex can wipe your memory.
Seen 10 things? Thanks to Jane Lidstone for this week's picture of 10 pedaloes on the River Dee in Chester.