Civil rights leaders, including Dr. Martin Luther King, Jr., sing "We Shall Overcome" at the conclusion of the Selma to Montgomery civil rights march in 1965.
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Smog blankets scyscrapers in Mexico City on March 17. The city is suffering its worst pollution in more than a decade, and cars are required to stay off the street one day a week.
Paul Zakayo (left) and Nasa Jackson Mairi were nabbed by a team of park rangers at the Mara Conservancy in Kenya and charged with killing three impalas and a gazelle in the wildlife sanctuary.
Ian Burkhart prepares for a training session in Columbus, Ohio. To move muscles in Burkhart's hand, the system relies on electrodes implanted in his brain, a computer interface attached to his skull, and electrical stimulators wrapped around his forearm.
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