11-15-2001 - Biodiversity

sagar: Author=’Eleanor Imster’ program=’3237′ video=”Ripe coffee beans on the tree_JB:_ This is Earth and Sky. One-seventh of the land on Earth is desert. But not all deserts are hot – some are extremely cold. What makes a desert a desert is what it lacks – water. All deserts are extremely dry.

_DB:_ To survive, desert animals have had to adapt to accommodate for this scarcity of water. Take the kangaroo rat – a small rodent that resembles a gerbil and gets its name because it jumps around like a kangaroo on long, powerful hind legs. Kangaroo rats live in the deserts of the southwestern United States and Mexico. They stay in their underground burrows during the day to keep cool. Kangaroo rats only come out at night to gather seeds – which they stuff into their fur-lined cheeks.

_JB:_ The kangaroo rat never drinks water. Their bodies have the ability to produce tiny amounts of water when the food inside them combines with the oxygen that they breathe. And they don’t waste the water they’ve got. Kangaroo rats don’t sweat or pant the way other animals do to keep cool. They also have specialized kidneys, that allow them to dispose of waste materials with very little output of water. In fact, their urine is so concentrated it crystallizes when it passes from their bodies.

_DB:_ That’s our show for today – made possible by the “National Fish and Wildlife Foundation”:http://www.nfwf.org/, in cooperation with the “U.S. Forest Service”:http://www.fs.fed.us/. We hope you’ll visit our web site at earthsky.com. We’re Block and Byrd for Earth and Sky.

Written by EarthSky