Features

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  Color Vision: How Our Eyes Reflect Primate Evolution

  Analyses of primate visual pigments show that our color vision evolved in an unusual way and that the brain is more adaptable than generally thought

  Gerald H. Jacobs and Jeremy Nathans   | April 1, 2009  | 20

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  Does Dark Energy Really Exist?

  Or does Earth occupy a very unusual place in the universe?

  Timothy Clifton and Pedro G. Ferreira   | April 1, 2009  | 123

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  How to Prevent the Next Pandemic

  An international network for monitoring the flow of viruses from animals to humans might help scientists head off global epidemics

  Nathan Wolfe   | April 1, 2009  | 5

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  Solving the Mystery of the Vanishing Bees

  The mysterious ailment called colony collapse disorder has wiped out large numbers of the bees that pollinate a third of our crops. The causes turn out to be surprisingly complex, but solutions are emerging

  Diana Cox-Foster and Dennis vanEngelsdorp   | April 1, 2009  | 61

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  Green Lasers: The Next Innovation in Chip-Based Beams

  Semiconductors can generate laser light in all colors except one. But new techniques for growing laser diodes could soon make brilliant full-spectrum displays a reality

  Shuji Nakamura and Michael Riordan   | April 1, 2009  | 12

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  Soldiers' Stress: What Doctors Get Wrong about PTSD

  A growing number of experts insist that the concept of post-traumatic stress disorder is itself disordered and that soldiers are suffering as a result

  David Dobbs   | April 1, 2009  | 98