A replica of the pinky bone fragment found in a Siberian cave. Researchers used the bone bit to extract and sequence the genome of a girl who lived tens of thousands of years ago. Max Planck Institute for Evolutionary Anthropology hide caption

toggle caption Max Planck Institute for Evolutionary Anthropology

Research suggests basic forms of learning are possible while snoozing. iStockphoto.com hide caption

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Lance Armstrong competes in the Ironman Panama 70.3. triathlon in Panama City, Panama. Arnulfo Franco/AP hide caption

toggle caption Arnulfo Franco/AP

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