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There was a time when our ancient ancestors' hands had digits that all pointed the same way tipped with claws. But our primate ancestors changed that. We've lost our claws and now have na...

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This story begins on a cold grey morning in 1683 in England.Molly Walesh sat on the stool,pulling at the udder of a difficult cow.She was a milkmaid.She had to get up very early every morning and go t...

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When my great grandma Anna came to America.She wore the same thick coatand big boots she had worn when she worked on her family's farm.But her family did not farm anymore.In New York City,her father c...

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Walking on two legs marked a huge change for our species. In fact, being almost exclusively bipedal makes us unique among our primate cousins. The question is, how did our ancestors start...

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In some areas,the Vikings became so powerfulthey built temporary bases.These temporary bases sometimes became permanent.Later, many Vikings stayed in Britain.Many English words used today come from th...

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More people are trying to learn English than any other language in the world.English is the language of political negotiations and international business.It has become the international language of sc...

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SPEAKER: The sweet, energetic glucose molecule is the energy source providing power for your living cells. Glucose, from the food you eat, is slowly broken down into two pyruvate molecule...

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MALE: The product of glycolysis. The pyruvate molecule is the source of carbon and electrons for aerobic respiration reactions inside your mitochondria. Pyruvate enters pores on the mit...