There are actually seven different types of twins: Identical, Fraternal, Mirror-Image, Polar Body (Half Identical), Mixed Chromosome, Superfecundation, and Superfetation.
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Humans are capable of running 40 mph according to a study by bio-mechanical expert Dr. Matthew Bundle. Today's fastest man, Usain Bolt, has a top speed of 28 mph.
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Women have a slightly higher average IQ than men.
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The world's tallest man reached 8 feet 11 inches at 21.
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The world's shortest man measures only 21.5 inches.
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About 2/3 of American men prefer boxers to briefs.
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On average women can hear better than men.
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