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About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
The average office desk has 400 times more bacteria on it than a toilet.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
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