A replica of the world's best preserved wooly mammoth, a 40,000-year-old baby named Lyuba who was discovered in Siberia in 2007, is displayed for the media in a fossil storage room at Chicago's Field Museum. The Field Museum will be the first in North America to display Lyuba's body currently undergoing analysis in Russia. Sucked to her death in a muddy river bed, the baby wooly mammoth spent 40,000 years frozen in the Siberian permafrost, where her body was so perfectly preserved that traces of her mother's milk remained in her belly. Photo courtesy: AFP.