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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
There are approximately 3 million unintended pregnancies in the United States each year.
There are more sensory neurons in the tongue than in any other part of the body.
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