ADVANCE FOR WEEKEND EDITIONS OF JAN. 26 - In an April 7, 2011 photo researcher Chris Smith examines a Yucca moth gathered in the Mojave Desert. The iconic plant of the Mojave Desert provides a perfect example of what scientists call coevolution. The Joshua Tree and the Yucca moth have developed together and now they depend on each other for reproduction. (AP Photo/Las Vegas Review-Journal, Jessica Ebelhar)
