A man holds a handful of coffee beans during the first day of the World Coffee Conference in Guatemala City on Feb. 26. Coffee producers say they are getting hammered by global warming, with higher temperatures forcing growers to move to prized higher ground, putting the cash crop at risk. Johan Ordonez/AFP/Getty Images hide caption

For athletes and nonathletes alike, stretching to keep muscles limber may help prevent cramping later in life. Ian Stewart/AP hide caption

Staff Sgt. Norman T. Hatch was a cinematographer and combat photographer during World War II. He won an Academy Award for his footage of the amphibious assault at the Battle of Tarawa in 1943. U.S. Marine Corps Combat Correspondents Association hide caption

Five fossilized human skulls show how the shape of the early human face evolved: (left to right) Australopithecus africanus, 2.5 million years old; Homo rudolfensis, 1.9 million years old; Homo erectus, 1 million years old; Homo heidelbergensis, 350,000 years old; Homo sapiens, 4,800 years old. Scientists believe that climate change had a major impact on the development of early humans. Chip Clark, Jim DiLoreto, & Don Hurlbert/Smithsonian Institution hide caption