Old bones are big business. In conditions that range from trying to perilous, fossil hunters cross the globe in search of mammoth tusks and trilobites. Collectors from the Carnegie Museum of Natural History to Charlie Sheen compete to acquire the most appealing specimens. But it's not all adventure and intrigue: There's also an intense ideological battle over the ethics of selling a natural resource.
Lou Simons, author of "Fossil Wars: Dispatch from the Front Lines" in the new National Geographic Magazine