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facial expressions based on survival

Why do our eyes open wide when we feel fear or narrow to slits when we express disgust? It has to do with survival. In a paper in the journal Psychological Science, researchers concluded that expressions of fear and disgust altered the way human eyes gather and focus light. They argued that these changes were intended to help humans survive, or at least detect, threats. Study authors said their findings supported the view of Charles Darwin, who argued that expressions did not necessarily originate for communication and were not arbitrary. They wrote, "Our expressions probably adhere to some underlying universal functional principles."

Gulf oil spill still imperils tuna

The BP Deepwater Horizon oil spill struck at the very heart of fish, a new study says. Exposed to millions of gallons of crude, young tuna and amberjack, some of the speediest predators in the ocean, developed heart defects that are likely to limit their ability to catch food. The findings of the study, led by the National Oceanic and Atmospheric Administration, have grim implications for the future of yellowfin and bluefin tuna, as well as amberjack, that were embryos, larvae or juveniles when the spill occurred during tuna-spawning season in the northern Gulf of Mexico in April 2010. Embryos are highly sensitive, so fragile that it is possible to see through them. Nat Scholz, leader of the ecotoxicology program at NOAA's Northwest Fisheries Science Center in Seattle, said, "You're going to be losing those fish from the adult spawning population."

world's oldest masks on display

The oldest known masks in the world went on display in Jerusalem in the largest such exhibit. The 11 stone masks date back 9,000 years, and were fashioned at a critical turning point in the history of civilization, when humans in the Fertile Crescent abandoned the hunter-gatherer lifestyle and became farmers, said exhibit curator Debby Hershman. "It's the most important revolution that ever happened." The people who fashioned the masks, she said, "are actually the founders of civilization." The masks are thought to have been made to look like the skulls of dead ancestors, used in civilization's first public ceremonies.

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