STEVE INSKEEP, host:
It's MORNING EDITION from NPR News. I'm Steve Inskeep.
RENEE MONTAGNE, host:
And I'm Renee Montagne. Happy Halloween.
And now for a slightly spooky tale, a journey into the earth in search of undiscovered bugs. The tale takes place not in the Amazon, but in the caves of Tennessee. Tennessee has more than 8,000 known caves, the most it's said, of any state. Some cave creatures have never seen the sun, but they are feeling the effects of the people who live above them. Biologist fear some of these animals are going extinct before they're even discovered.
NPR's David Kestenbaum has the latest installment in our NPR National Geographic Radio Expeditions.
DAVID KESTENBAUM: In fairy tales, caves are guarded by dragons or trolls. This one - by cows. We park our cars by the edge of the field. It's raining out.
(Soundbite of car door closing)
And we walked a little ways into the woods. And there it is. Among the trees and the fall leaves, a dark opening, a way into the earth.
(Soundbite of zipper being zipped)
Jerry Lewis fiddles with hardhat and zips up his overalls. Lewis is one of the country's top cave biologists. He runs his own environmental consulting company and he is legendary for his ability to find new creatures. Lewis has been in over a thousand caves some require a wet suit.
Dr. JERRY LEWIS (Cave Biologist): If you're wanting the definition of grim -pushing one nostril all up against the ceiling of the cave, just enough to breath to get through between the water and the cave roof.
KESTENBAUM: He jokes that a good day is one where you can stop the bleeding.
Mr. CORY HOLLIDAY (Biologist, The Nature Conservancy): Whooo! Big spider.
KESTENBAUM: A man named Cory Holliday leads us over a medieval-looking gate into the cave's mouth. He has a long red beard, the sort of birds might happily nest in.
It's dark and wet - cold water up to our knees. Cory Holliday goes over the safety rules.
Mr. HOLLIDAY: You want to have three light sources. It's very easy to smack your headlamp on a low ceiling like this, and be completely without a light source.
KESTENBAUM: Without a light, you might never find your way out. Holliday works for the environmental group, the Nature Conservancy, which is looking out for the little guys here. It's paying for a scientific inventory of the small creatures that live in the darkness. The Conservancy is worried about things like the housing development that's going up next door. We're only about 40 miles from Nashville. Our headlamps reveal cave salamanders - bright orange and black - which scamper away into cracks.
Jerry Lewis barely looks, he's after a smaller, stranger things. Some creatures never leave the cave. They don't even have eyes. It's amazing anything survives here. There's no light, no obvious plants to eat.
(Soundbite of trudging through water)
KESTENBAUM: The water gets deeper. And Lewis climbs up onto a kind of muddy shelf. He has a bit of a belly, but he slithers along pretty skillfully. He's amazing to watch.
Mr. LEWIS: If you stay over close to this side, it's (unintelligible). Stay low and you will reach (unintelligible) past you.
KESTENBAUM: Hundreds of millions of years ago, this land was the floor of an ocean. You can see shells and fossils in the walls. Those shells and the coral and sediment eventually became limestone. And water carved the limestone into caves. At the end of the crawl, we find the secret to life in this cave, a big mat of black material - bat droppings. That's how a lot of nutrients get here. Bats fly out, they eat, they come back in, and you know.
Mr. LEWIS: It's teeming with life. You can look down on it and see millipedes and little beetles just crawling around on it. This is like the smorgasbord for a cave animal.
KESTENBAUM: It's actually poop of an endangered bat. Lewis' scoops some into a Ziplock bag.
Mr. LEWIS: See I'll take this home and give it to my wife who's was doing her thesis on gray bats. And she would just think I'm the husband with the most-est.
KESTENBAUM: Cory Holliday seems to have disappeared. Then we see his headlamp in a tight space over to the left. We inch over on our stomachs. He's found a tiny insect called the pseudoscorpion. I don't how he found it. It's the size of an E in a newspaper.
Mr. HOLLIDAY: It's extremely small, but a pretty major predator. Decent size pinchers enough to grab the hold of any millipede that comes walking by.
KESTENBAUM: He could take down a millipede?
Mr. HOLLIDAY: Yup.
Mr. LEWIS: Yeah.
Mr. HOLLIDAY: Chop them in little pieces and eat them up.
KESTENBAUM: He sticks it in a jar of alcohol. Later, some scientist's big eyeball will peer down at it through a microscope.
Mr. LEWIS: This is wonderful.
KESTENBAUM: Jerry Lewis lies on his belly. His headlamp illuminates a delicate white insect with long, graceful antennae, a dipluran. If you found it in your bathroom, you'd probably kill it, but don't tell Jerry that.
Mr. LEWIS: It's an incredibly rare animal.
KESTENBAUM: They look ancient.
Mr. LEWIS: They are very, very primitive animals.
KESTENBAUM: It's funny what society has decided to protect. Pandas? Yes. Bats, butterflies? Sure. Diplurans? Uh uh.
Mr. LEWIS: Oh, look, we probably found, right here in this square foot in front of us, two new species of animals.
KESTENBAUM: You think so?
Dr. LEWIS: I'm pretty sure of it.
KESTENBAUM: Here's the thing about life in a cave - you don't often get the chance to mate with things in other caves. So these little creatures - after generation and generation, thousands of years - evolve and sometimes become their own species, unique in the world.
Dr. LEWIS: The cave animals, the beetles, the millipedes, the spiders of Tennessee caves are relics of the Ice Ages. And are now, for all intents and purposes, trapped in Tennessee caves.
KESTENBAUM: Some animals that used to see, grow blind in caves. It's like evolution in reverse. The caves here have blindfish. Cory Holliday says he's seen them dart precisely in and out of holes even though they don't have eyes. And some animals here have really slow metabolisms because of the cold and the lack of food. He says some cave crayfish can live to be over 100 years old.
Mr. HOLLIDAY: It's one of the reasons we're so cautious and careful when we come in here, you know. You can imagine, you know, to accidentally stepping on something that's older than your grandparents. It's been here a long time.
KESTENBAUM: We stepped on something else. I think it's a rock but then I see it has letters on it: E-T-C-H. Ketchup, Cory Holliday says. Up on the surface, people throw trash into sinkholes thinking the stuff will just disappear.
Mr. HOLLIDAY: And more often than not, that sinkhole will drain into a cave.
KESTENBAUM: But this is the other end. This is where all the trash washes out.
Mr. HOLLIDAY: This is where it all ends up. It doesn't actually just go away.
KESTENBAUM: We also find condom wrappers and an old beer bottle, which were probably carried in. We explore four caves in total. Holliday and Lewis set traps for insects, baited with rotting Limburger cheese spread. It smells.
The inventories sometimes list over a dozen species in a cave.
Meanwhile, the cave sets a trap for us. Mud grabs our boots. We have to yank them free. It's clear we are the intruders. Hours go by like this. It's unclear how long we're in here. Jerry Lewis does not wear a watch.
We're above ground now, by a highway and a strip mall. There's a cave around here somewhere and it runs underneath the interstate. We find the entrance by a creek, and Lewis, who has seen scores of caves, is stunned.
Dr. LEWIS: This is one of the strangest things I've ever seen in a cave. This is really weird.
KESTENBAUM: The cave has a bed with a blanket and a pillow.
Dr. LEWIS: A couch. It's got some chairs, a mirror, an American flag, a little sign that says entrance.
KESTENBAUM: Someone is living here. Lewis goes to explore the cave. He turns over some rocks but finds almost nothing alive. It's unnaturally warm for a cave. Something is wrong. Then he does something you never see.
Dr. LEWIS: This place creeps me out. Let's get out of here.
KESTENBAUM: He flees, worried we might be walking in toxic sewage. He says he ended up in a hospital once from a cave like this.
Dr. LEWIS: This is the dead wreckage of a cave community, a great place that's no longer. All we have left here is an epitaph.
KESTENBAUM: The inventory for this cave is easy: one caveman.
For Radio Expeditions, this is David Kestenbaum, NPR News.
MONTAGNE: Radio Expeditions is a co-production of NPR and the National Geographic Society. And want to see a spooky, see-through crayfish and other creepy creatures, plus hear Podcasts? Visit NPR.org/radioexpeditions