Tom Uhlman

"In the 1990s, scientists lived inside Biosphere 2 (Biosphere 1 is the Earth itself) for two years, trying to figure out if colonizing Mars would ever be possible. Now scientists don't live there but instead conduct all sorts of studies and experiments aimed to help us better understand our environment and especially understand what sort of things are happening to it due to climate change and other man-made problems. It's a unique take on the Scientists...

The national parks have been called "America's best idea" -- and some of the best scientific ideas are happening right now inside these protected American spaces that welcome more than 270 million visitors each year. Meet up with scientists studying geysers, grizzlies, salamanders, cacti, and fireflies in some of America's most treasured places: our national parks.