Pulse of the Planet is a weekday radio show that "provides its listeners with a two-minute sound portrait of Planet Earth, tracking the rhythms of nature, culture and science worldwide and blending interviews and extraordinary natural sound."
 

Program #2583 January 2002 Caves: Living Fossils   Listen to this program in MP3 Listen to this program in streaming audio ambiance: cave diving ambience, bubbles Divers exploring the depths of underwater caves have made a startling discovery —primitive animals whose ancestors have been swimming in the darkness for millions of years. I’m Jim Metzner, and this is the Pulse of the Planet. Dr. Tom Iliffe is a professor of marine biology at Texas A&M University. He and other researchers have explored hundreds of deep saltwater caves around the world in such places as Hawaii and the Yucatan Peninsula. He describes a dive into one of these caves as a trip back in time. “Many of the animals that we find there are essentially living fossil species. They’re really very primitive forms of life that probably have existed on Earth for tens of millions of years and been isolated. These are animals that have adapted to life in the caves. They have lost their eyes, they have lost their pigment, features that they really don’t need in the totally lightless underwater caves. One tiny animal, called Remipedia, may have existed in these pitch-black depths since the days of the dinosaur. “One of the most interesting animals that we’ve found in these underwater caves is a very primitive type of crustacean called Remipedia. Remipedia is a new class of Crustacea. It’s like nothing else that’s known on earth. Superficially it looks like a centipede, and it does spend all it’s life swimming endlessly through the cave waters. And it’s nearest relatives perhaps are known only from fossils that may date back fifty million years or more.” In a future program, we’ll hear how one species of living fossil came to be found in two different caves on opposite ends of the earth. First broadcast on 23-JAN-02

Other Pulse of the Planet episodes:

Cave Diving Mars Connection Ancient Life