National Geographic: Wild South West

In less than 100 miles; the "Tale of Two Extremes" takes us from the lowest and hottest point in the lower48; to its highest and coldest peak. This is one of five unlikely journeys we explore for a unique look atwhat attracts wildlife to seemingly inhospitable landscapes. From the fur-clad bears on the treelessmountain tops of Big Bend National Park; to the twenty million bats that pour out of Bracken Caveevery night to form the largest concentrations of mammals on the planet - WILD SOUTHWEST delivers asurprise twist at every turn.