Watch as global population explodes from 300 million to 7 billion.

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Tents pitched at the Occupy Wall Street encampment at Zuccotti Park in New York. The protests are part of a growing distrust in America of government and public institutions.

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The Occupy Wall Street protests have inspired similar events around America, and in dozens of countries. Here, a truck has been painted with a sign supporting the Occupy Portland protests in Oregon.

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Dan Wheldon, of England, smiles during driver introductions for the IndyCar Series Las Vegas Indy 300 auto race Sunday, Oct. 16, 2011, in Las Vegas. Wheldon, a two-time Indianapolis 500 winner, died following a crash in the race.

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If the Nobel Peace Prize is to go to someone involved with the Arab Spring, it may be difficult to choose who gets the award. Here, men celebrate in Tunis after President Zine El Abidine Ben Ali said he would not seek another term.

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