A man pours earth Wednesday onto a grave of one of the workers who died last week in the building collapse in Bangladesh. Wong Maye-E/AP hide caption

itoggle caption Wong Maye-E/AP

Bolivian President Evo Morales sings his national anthem during the annual May Day march in La Paz on Wednesday. He announced during a speech that he was expelling the U.S. Agency for International Development from the country. Juan Karita/AP hide caption

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The four cuts at the top of this skull "are clear chops to the forehead," says Smithsonian forensic anthropologist Douglas Owsley. Based on forensic evidence, researchers think the blows were made after the person died. Donald E. Hurlbert/Smithsonian hide caption

itoggle caption Donald E. Hurlbert/Smithsonian

Harvey Mudd President Maria Klawe often uses her longboard to get around campus and chat with students like senior Xanda Schofield. Wendy Kaufman/NPR hide caption

itoggle caption Wendy Kaufman/NPR

In this image taken from video, South African President Jacob Zuma sits with ailing anti-apartheid icon Nelson Mandela on Monday. Mandela was hospitalized in late March with a lung infection, and in images from the visit, appeared largely unresponsive. SABC/AP hide caption

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Bates experienced migraines as a child. She made this painting to depict how they felt to her. Courtesy of Emily Bates hide caption

itoggle caption Courtesy of Emily Bates

Soldiers with the British Machine Gun Corps wear gas masks in 1916 during World War I's first Battle of the Somme. General Photographic Agency/Getty Images hide caption

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The Treasury Department announced this week it will pay down some of its debt for the first time in six years. Jacquelyn Martin/AP hide caption

itoggle caption Jacquelyn Martin/AP