Mon December 5, 2011
The Deep-Sea Find That Changed Biology
Originally published on Wed May 23, 2012 10:14 am
In 1977, a small crew of oceanographers traveled to the bottom of the Pacific Ocean and stumbled across a brand new form of life. The discovery was so unusual, it turned biology on its head and brought into question much of what scientists thought they knew about where life can form and what it needs in order to survive.
Today, the Smithsonian Institution houses that remarkable discovery: a pale and fleshy, 4-foot-long worm that floats in the kind of pickle jar you'd see in your neighborhood delicatessen. It might not look like much now, but Kristian Fauchald, the Smithsonian's curator of worms, says that in 1977, this worm had everyone scratching their heads. At up to 7 feet in length, he says, "these are enormous beasts compared to normal worms." And they were thriving in large numbers without any obvious source of food or light.
"This," Fauchald says, holding up the worm, "is something absolutely unique."
An Unexpected Discovery
Kathy Crane and Jack Corliss weren't expecting to find anything alive when they started on their journey to explore the ocean floor. They were looking instead to answer some basic questions about the ocean's temperature and chemistry that science could not yet answer. "Saltiness was a big question," Crane says. "Students used to ask their professors, 'How did the ocean get its salt?' "
Some ocean scientists believed the answers to these questions lay in volcanic vents that they suspected peppered the ocean floor. So they put together an expedition in the Alvin, a tiny submarine operated by Woods Hole Oceanographic Institute, to go down and see for themselves.
Crane was then a 25-year-old grad student from the Scripps Institution of Oceanography. From the Alvin's mother ship, she guided the Alvin to an area in the eastern Pacific known as the Galapagos Rift. Corliss, a geologist from Oregon State University, rode aboard the Alvin itself.
The day of the dive, Crane assumed her position as navigator and Corliss climbed aboard the Alvin. "I slipped through the porthole," he remembers. "It wasn't much bigger around than I was."
As the Alvin began its descent, Corliss watched through the window as the world around him went from blue to black to blacker than black. "We were descending into a different world," he says. Now and again, they saw sudden flashes of light from bioluminescent creatures swimming past the sub.
Back on the mother ship, Crane navigated the team toward the areas where they believed the vents were located. She also told the Alvin's pilot to look for "white clam shells against a background of black volcanic glass." From earlier imaging, they'd caught glimpses of what they thought were clamshells on the ocean floor, which they joked were tossed overboard from a Navy ship's clambake. It never occurred to the crew inside the sub that the shells were anything special. Until ...
"I was watching my temperature measurement," Corliss says, "and just that time, the pilot said, 'There's clams out here!' "
They'd found not just clamshells, but living, breathing clams that were a good foot-and-a-half long living alongside the hydrothermal vents. There were also mussels, anemones and brilliantly colored red-tipped worms — up to 7 feet long and anchored by slender white tubes swaying like a field of flowers.
"Absolutely stunningly beautiful," Corliss says. "The worms had white tubes and these beautiful red plumes, sort of like a three-dimensional feather. These feathers are sort of oscillating, undulating as they're pumping fluid into their body. It was amazing!"
The crew named the lush pocket of life "the Garden of Eden" and used the sub's mechanical arm to delicately gather up a bouquet of worms, mussels, clams and anemones. Once on the surface, they dropped them into containers of vodka — the only preservative they had. Then Crane picked up the phone and called Woods Hole.
"Hey," she asked, "can you biologists tell us what these things are? And they said, 'What? We don't know what that is. Hold everything!' "
'How Do They Live?'
Today, back at the Smithsonian, Kristian Fauchald opens up a pickle jar and pulls out the very first worm — Riftia pachyptilla — that Crane and her team brought up from the depths 34 years ago. "The really fun part," he says, "was trying to figure out what these animals are. How do they live?"
The key, he says, is that the worms don't use light but a "completely different energy source" in a process called chemosynthesis. The worm uses its red plume to absorb hydrogen sulfide — that nasty stuff that smells like rotten eggs — from the vent water. A colony of bacteria living inside the worm's gut gobbles up the hydrogen sulfide and uses it to create carbon compounds that feed the worm. Voila — chemosynthesis!
In the months following the discovery of life near the hydrothermal vents, Crane says the excitement was intense, and the scientific community's biggest names came steam-rolling in.
"There were cases where people were stealing samples, clams and taking them off to their institutions and hiding them," she says. "You know, scientists can be extremely aggressive people to get what they want."
Eventually, Crane left the field of vent science. Today she is a senior researcher at the National Oceanic and Atmospheric Administration, working mostly in the Arctic.
Corliss says the discovery inspired him to change the focus of his work as he wondered whether these curious creatures, from such an inhospitable environment, might help explain how life started on Earth.
"It was quite amazing," he says. "It marked a transition in my life." Corliss has since devoted his career to studying the origins of life; today, he teaches biology at the Central European University in Budapest.
In the years since the original discovery, scientists have returned to the Galapagos Rift and the hydrothermal vents. The abundant "Garden of Eden" continues to thrive, and not far away, a new vent community of chemosynthetic life has begun to grow. Scientists have named the new site "Rosebud."
LINDA WERTHEIMER, HOST:
It's not often a scientist discovers a new form of life, but that happened to two people who once traveled to the bottom of the Pacific. The creature they found is now in a warehouse at the Smithsonian Institution near Washington. NPR's Christopher Joyce went there looking for lost treasures of science, and he has this story of Alvin and the worm.
CHRISTOPHER JOYCE, BYLINE: It's a room the size of a basketball court. Kristian Fauchald spins a big wheel and metal cabins roll apart to form aisles. It's gloomy inside. Light filters through jars with pale, fleshy things floating in them. Kristian is the Smithsonian's curator of worms.
KRISTIAN FAUCHALD: The study of worms used to be sort of a gentlemanly occupation that nobody particularly cared about. That's no longer the case.
JOYCE: Kristian stops in front of what looks like a pickle jar from a neighborhood delicatessen.
FAUCHALD: It is a pickle jar. It's a very large pickle jar.
JOYCE: Inside a grayish, four-foot-long worm floats in formaldehyde. It's the first one of its kind discovered. Its name is Riftia pachyptilla. The weird thing about this worm is it was found at the bottom of the ocean. Scientists who found it in 1977 were not expecting to find animals like that at the sea bottom.
FAUCHALD: The deep sea is considered a desert. There is very little food for anybody.
JOYCE: But Riftia pachyptilla isn't just anybody.
(SOUNDBITE OF CLANGING)
JOYCE: In the mid-1970s, the field of ocean science was full of excitement. An amazing submarine, the tiny Alvin operated by the Woods Hole Oceanographic Institution in Massachusetts, was taking scientists to depths they'd never been to before.
UNIDENTIFIED WOMAN: (Unintelligible) 12519...
JOYCE: Scientists were especially interested in something they'd found near the Galapagos Rift in the Eastern Pacific: a volcanic vent 8,000 feet below the surface. They wanted to know where the ocean was getting its salt and its heat and was it coming up from a volcanic vent. A research ship carried the Alvin there to find out.
KATHY CRANE: I was navigator.
JOYCE: Kathy Crane is an ocean scientist. She knew how to find the volcanic vent. With her on the trip was Jack Corliss, a geologist. Jack was on that first dive.
JACK CORLISS: When you get into it, you climb on the deck and step through the porthole.
CRANE: Everybody is sort of sitting in a fetal position, I think pretty much. You're in this cramped environment. It gets really cold on the sea floor, and so you take down sleeping bags.
CORLISS: After we left the surface, we were descending into a different world.
JOYCE: It took almost three hours to get to the bottom. The crew listened to music and watched it get darker and darker.
(SOUNDBITE OF MUSIC)
CORLISS: If you put your face up to the porthole every once in a while, you would see a flash go by because there were organisms that were bioluminescent, and they would turn on their lights.
JOYCE: Kathy was in the mother ship on surface. She was guiding Alvin to where underwater cameras had earlier seen the vent. Clam shells marked the spot. They thought they'd been dropped there by a passing ship.
CRANE: My guidance to them was look out the porthole and where you see white clam shells against a background of all black volcanic glass, then you'll be there.
CORLISS: I was watching my temperature measurement, and just at that time the pilots said there's clams out here.
UNIDENTIFIED MAN: This is 12-02-27. Right down there. See, look at the clams and to the left of them...
CORLISS: Yeah, you're right. No question...
UNIDENTIFIED MAN: That's an anomaly.
JOYCE: Living clams, not just shells. In fact, there was lots of life there, strange life - foot-long clams, mussels, crabs, right next to this toxic, boiling vent.
CRANE: So stunning, just beautiful, peaceful aqua-colored water and animals just lazily drifting in this spa-like water, like a Garden of Eden.
JOYCE: And then there were the worms - three, four, five, maybe six-feet long in slender tubes that rose from the rocks like a field of flowers.
CORLISS: White tubes and these beautiful red plumes, and it's sort of like a three-dimensional feather, this plume, bright red, oscillating, undulating. It was amazing.
JOYCE: It was the first time humans had visited a deep-sea event. The scientist inside the Alvin used a mechanical arm with meat-like pinchers to delicately grasp some of the creatures.
CRANE: We're bringing up these things and all we had to package them in was vodka.
JOYCE: They'd never expected to find animals down there.
CRANE: We called up Woods Hole to ask, hey, can a biologist tell us what these things are? And they said, what? We don't know what that is. Hold everything.
CORLISS: This is the first time anyone had seen a living community of organisms that was based only on chemicals, not energy from the sun. We started talking about it all on the ship: Could this have something to do with the origin of life?
JOYCE: And that's the reason they keep the worm at the Smithsonian, where I got a chance to actually hold it. It's squishy, rubbery, wormlike, but with some hard parts.
(SOUNDBITE OF CLICKING)
FAUCHALD: This is the curved structure.
JOYCE: A collar around it.
FAUCHALD: Like a collar, yeah.
JOYCE: Kristian Fauchald explains that the worm doesn't have a digestive system. Instead, it uses its plume to absorb a nasty chemical from the vent water – hydrogen sulfite, that stuff that smells like rotten eggs. The worm feeds the chemical to a colony of bacteria that lives inside its body. The bacteria essentially eat hydrogen sulfite, and in so doing, they create carbon compounds that feed the worm. Kristian says Jack Corliss was right to think that this might have been one way the first creatures on Earth lived – underwater, without light or much oxygen, feeding on chemicals.
FAUCHALD: We have always thought that, oh well, all energy comes from the sun. Now some of it comes from inside of the globe.
JOYCE: The discovery rocked biological science, and for Kathy Crane, it was a personal victory in a man's world.
CRANE: In the early days it was very difficult because some of our advisors just wouldn't even take us out to sea since we were female. Yes, I was pissed off. You know, you just sort of buried inside you.
JOYCE: But she says the discovery was thrilling, although it didn't bring out the best in everyone.
CRANE: So many people, very prominent scientists, just came steamrolling into this field. And there were cases where people were stealing samples, like clams and things, and took them off to their institutions and hid them. And, you know, scientists can be extremely aggressive people to get what they want.
JOYCE: Too aggressive, Kathy thought.
CRANE: And I decided I don't want to be part of this anymore.
JOYCE: Kathy's now a senior researcher at the National Oceanic and Atmospheric Administration and works mostly in the arctic. Jack Corliss now teaches science at the Central European University in Budapest. He says he never anticipated being part of a discovery so grand. After that trip, he dedicated himself to studying the origins of life.
CORLISS: That was a transition in my life. At that point my life turned into a movie. It was quite amazing. I get emotional talking about it.
JOYCE: Scientists went back to the Galapagos Rift nine years ago, to the Garden of Eden, the place that remade biology. It was covered over with lava. But nearby a new colony of animals had formed. The scientists called it Rosebud. Christopher Joyce, NPR News. Transcript provided by NPR, Copyright National Public Radio.