Jan 28, 2019 05:35
About hedgehogs:
Hedgehog (European) Hedgehogs have about 5000 spines. Each spine lasts about a year then drops out and a replacement grows.
Why sharks don't get cavities:
“(The surface of) shark teeth contains 100 percent fluoride. In principle, sharks should not suffer from cavities. As they live in water and as they change their teeth regularly, dental protection should not be a problem for sharks.”
Where did nickel get its name?
Nickel gets its name from the German word "kupfernickel" which means "devil's copper." German miners named ore containing nickel "kupfernickel" because, although they thought the ore contained copper, they were unable to extract any copper from it. They blamed their troubles with this ore on the devil.
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