"You know Marlow in Heart of Darkness, the guywho's the narrator, the captain?" Cindy Lee Van Dover,a deep-sea biologist, is sitting in the cafeteria of the R/VKnorr, one day out of Mauritius. Her wavy, neck-length hair isstreaked with gray; she wears a floral print shirt, a denim miniskirt,sandals, and a simple necklace. "In the beginning of the book," she con-tinues, "Marlow talks about liking maps. And back then the blank spaces wereon the continents. He'd look at them and point to one and say,'When I grow up, I will go there.' For me, looking at the midocean ridge—I walk around with this image of it in my mind all the time—there are just these big voids. And I think, 'When I grow up, I will go there.'
The midocean ridge, a mountain range that winds around the planet through every ocean, is as unfamiliar to most of us as the Congo was to Marlow, because its peaks are hidden by thousands of feet of water. Yet the ridge shapes Earth's surface. Its crest is a volcanic rift zone, where crustal plates spread apart and molten rock erupts to form new seafloor. It also alters the composition of seawater by spewing metals and other elements from volcanic hot springs. And those hot springs, called hydrothermal vents, are home to some of the most bizarre animals on Earth, animals that draw their energy not directly from the sun but from the sulfide and methane emanating from the vents. In fact, many researchers now think that life on Earth may have begun at hydrothermal vents.
Since the first vent site was discovered in 1977 off the Gal‡pagos Islands, some two dozen more vents have been studied; Cindy has been at it since 1982. But all have been in the Atlantic and Pacific oceans. The Indian Ocean has remained a blank space on the map, one that Cindy and her colleagues on the Knorr—geologists, chemists, and other biologists—are now heading into.
They had to wait seven years, since they first planned this expedition, for money and a ship. Twice the National Science Foundation (NSF) rejected their proposal. The third time the proposal was accepted, but the budget was cut to $400,000. There is not enough in that budget to cover the salaries of the researchers while they are on the Knorr—many oceanographers work for "soft money," meaning they have to raise their own salaries each year by obtaining grants—nor to cover the analysis of the samples and data. Counting the operating expenses of the Knorr and Jason, the tethered robot the researchers will use to explore the seafloor, this expedition is costing about $1.5 million—1/300 the cost of a single space-shuttle launch. But if the researchers had said no to the NSF, there would have been no trip at all.
Grant officers at the NSF named Cindy chief scientist partly because they wanted the expedition to focus on one of her specialties, biogeography. A key goal would be to study animals that live at Indian Ocean vents and how they relate to animals found at vents in the Atlantic and the Pacific. Soon after I joined the science party, however (Cindy had invited me along both as a reporter and as her assistant), I began receiving a stream of e-mail memos from another expedition member, marine geologist Dan Fornari of the Woods Hole Oceanographic Institution. The memos concerned endless logistics for getting 35 scientists and technicians from all over the United States, as well as their gear, onto a ship in the Indian Ocean. Are there enough freezers on board? Has everyone turned in his customs declaration? Dan, not Cindy, organized the cruise, as he had organized many previous ones. After I met him and saw him tearing around the Knorr, excess energy radiating from his wiry frame, I appreciated how suited to the role he was. But he didn't stop organizing once the expedition started, when Cindy was supposed to be in charge.
There was another source of tension: During the long wait for a ship, the researchers were beaten to the punch. In August last year, a Japanese team located the first hot spring in the Indian Ocean. The site had black-smoker chimneys swarming with shrimp, as had been seen at Atlantic vents, and clusters of other animals that resembled western Pacific species. But the Japanese had discovered the vent only on the last day of their cruise, so it was possible they had missed something spectacular. And Cindy hoped the Americans would discover an entirely new site with animals no one on Earth has seen—just as no one had seen or imagined giant tube worms with crimson plumes before they were discovered off the Gal‡pagos Islands.
"I don't mean to sell myself as a 19th-century scientist," Cindy said in an e-mail before the cruise, "but really what we are about is what Wallace and Darwin were doing in terrestrial systems more than a century ago. Most people imagine we have the basic patterns of life on our planet pretty well defined, yet here we are with entire ocean basins where we have yet to take a close look. If there were tube worms in the Pacific and 'blind' shrimp in the Atlantic, what does the Indian Ocean hold for us? We don't know, but we mean to find out."
Friday, March 30, Mauritius All the scientists are on board. The Knorr is fully packed with 70 tons of equipment. We sail in a few hours, and so it is not too soon to discuss the question: Where is this ship going?
For the nine principal investigators, as the NSF calls them, gathered around a table strewn with seafloor maps in the Knorr's main lab, the Japanese discovery has changed everything. They had always planned to start their search 450 miles east-southeast of Mauritius, at a latitude of 24 degrees south on the Central Indian Ridge, which runs north to south. Expeditions in the 1980s had found chemical signals of a hot spring there. The Japanese had located a vent a bit further south—25 degrees 19 minutes south, 70 degrees 2 minutes east. Clearly the thing to do, because the Japanese were unable to explore it completely, is to go directly there. If nothing else, the biologists will be able to fill their freezers and formalin jars with "meat"—as they sometimes refer to the animal tissue they collect. Then they won't be in danger of going home empty-handed. But what should be done with all the time saved as a result of not having to hunt for the vent?
Cindy has put her finger on another blank space. Just south of the Japanese site, called Kairei Field, the Central Indian Ridge joins the Southwest Indian Ridge (which heads toward the Atlantic) and the Southeast Indian Ridge (which heads toward the Pacific). Both are essentially unexplored. But hints of a vent have been reported on the Southwest Indian Ridge. Cindy wants to go there.
If they stick to the original plan and hunt down a vent at 24¡ South, she argues, they will almost certainly find much the same fauna as at Kairei, because the two sites are only 100 miles apart. On the other hand, the distance to the best candidate site on the Southwest Indian Ridge is around 750 miles. The rift valley there is at least 2.5 miles deep; any hot spring there might be the deepest yet. At such high pressure, perhaps the animals would be different. More than anything, Cindy wants to find animals that are different.
But first the researchers would have to find a vent on the southwestern ridge, and the hunting ground there is much larger and less well-defined than it is at 24¡ South. That worries the geochemists—Bob Collier of Oregon State University, Marv Lilley of the University of Washington, and Karen Von Damm of the University of New Hampshire—because the burden would be on them. They find a vent by "tow-yo-ing" a package of water sensors and sampling bottles over the seafloor, reeling it up and down like a yo-yo, and hoping it will pass through a plume of "smoke"—hot metal-laden water—that billows from the vent. Then they have to figure out where the smokestack is. It can take days or even weeks. Usually the chemists and geologists go out by themselves so they won't have bored biologists looking over their shoulders.
The biologists side with Cindy; the chemists and Susan Humphris, another Woods Hole geologist, are skeptical. Then there is Dan. As a geologist, he would prefer to map one segment of the Central Indian Ridge thoroughly. He can't accept Cindy's justification for giving up on 24¡ South. "It's the distance, Dan!" Cindy says in frustration.
Sunday, April 1, 22¡57' South, 64¡33' East Andy Bowen, head of the team of engineers who operate Jason, stands on the aft deck, surrounded by heavy machinery and a cluster of scientists. The giant drum next to him, he explains, holds five miles of steel-armored electro-optical cable, which carries electric power and control signals down to Jason and live video and other data back. The cable used to be more than a mile longer; over the years damaged pieces have been cut from it. "It's really at the end of its lifetime," Andy says.
Jason doesn't hang directly from that cable; if it did, every wave that hit the ship would jerk the robot around viciously. Instead the cable runs to Medea, a simple steel frame equipped with a few sensors, some lights, and a black-and-white camera. Medea isolates Jason from the ship's motion while Jason motors around underneath it on a 100-foot umbilical—24 hours a day, in principle.
Monday, April 2, 24¡43' South, 68¡49' East At today's meeting, Dan and Susan try to explain why going to 24¡ South rather than to the Southwest Indian Ridge would be geologically better. Basically, it comes down to the usefulness of having two nearby sites to compare. Cindy explains again that there is unlikely to be a biogeographical boundary between the two sites. Karen, the chemist, contradicts her; there could be chemical differences in the vent water, she says, that might produce differences in the fauna. And Dan reiterates his belief that being limited to "a data point of one" on the Central Indian Ridge would not even be doing biology correctly. "Where we go is a group decision," says Cindy. "But I think you should leave biogeography to the biogeographers."
Wednesday, April 4, 25¡19' South, 70¡02' EastIt takes Jason and Medea more than three hours to descend the mile and a half to Kairei. On the way down, white particles of marine snow—gooey flakes of dead plankton and other detritus—streak up toward Medea's downward-looking camera, then recede again, as the tender bobs with the ship. The bottom looms up first in that hazy black-and-white image, a moonscape of black rocks scattered in gray mud. It is strangely thrilling.
A moment later Jason moves into view under Medea, and we see the little cone of light cast by its headlights into the utter black. In the other monitors in the control room, in superbly clear color, we can see what lies ahead of Jason. Soon the moonscape is populated. The black, angular hunks of volcanic talus are speckled with white, flowerlike anemones measuring an inch or two across. A gray rattail fish undulates by. Then shrimp appear and begin to provide comic relief. First one, struggling by in the distance, its little legs furiously paddling, then another, bumping its head on Jason's basket. It has a pink, translucent abdomen and a swollen carapace.
Cindy rushes into the control van and tells us that it was a vent shrimp—probably of the genus Rimicaris, the kind that dominates vent sites on the Mid-Atlantic Ridge. Another shrimp appears suddenly and bounces off the camera lens. Cindy laughs delightedly. Yet another one comes into view, its gills blackened by volcanic sulfide. We must be near our goal. Dozens of shrimp are in view, careering this way and that like the atoms in a gas. "This ain't nothin' yet," says Cindy. "More to come."
And then, suddenly, we see it: a field of absurdly tall, needlelike spires of rock, packed closely together. Hot black smoke seeps from crevices. Swarming around these spires, thronging them in rustling layers, jostling each other to get their noses right up into the smoke, are pink shrimp an inch or two long. Susan zooms in the camera and we see the smoke curling up around the shrimp; some look a bit singed. A few mussels cling to the rock underneath them.
We find other chimneys. At the top of one, thick smoke gushes from a candelabra of conduits, merging into a roiling cloud. Near the bottom of another, a little metal flag gives a twinge—it's a Japanese marker. But the image that lingers as I finally clamber into my bunk, exhausted from hours of staring at video monitors, is the least spectacular. It's Jason as seen by Medea, a lonely silhouette at the end of its tether, piercing the darkness with a tiny cone of light.
Thursday, April 5, 25¡19' South, 70¡02' East Cindy is disappointed. All the vents at Kairei look the same—swarming with shrimp. She has spent years studying Rimicaris exoculata in the Atlantic. It was she who discovered that although Rimicaris lacks normal eyes, it has a light-sensitive organ on its back that it may use to home in on heat radiation from the vents. Shrimp-infested chimneys are beautiful, but as Cindy says at breakfast, "been there, done that. I was so hoping that the Japanese had missed something. I underestimated them." She wants to sample the animals and get out of here for the Southwest Indian Ridge as fast as we can.
Saturday, April 7, 25¡19' South, 70¡02' East The day everyone has been waiting for—the elevator comes back with samples. The elevator is a 6-foot-square platform loaded with Igloo coolers and Dan-built bioboxes, surmounted by a mast festooned with spherical glass floats. Anchor weights attached to the bottom carry the elevator to the seafloor; the floats will carry it back to the surface when Jason has filled all the boxes with samples and released the weights.
As the first full elevator arrives on deck, the biologists storm it. One loses a sample she thought was hers to another whose elbows were sharper. Biologists who study the physiology of organisms are under time pressure: They must dissect the organisms before they deteriorate. Colleen Cavanaugh, a microbiologist from Harvard, needs animals that are alive and not starved; once they've been away from their vent too long, even if they've been sitting in a box on the ocean floor, they start to digest the symbiotic bacteria in which she is interested.
Cindy, who hates being rushed, is under a different pressure. She wants to look at all the animals, get a sense of the whole ecosystem. Not just the shrimp and snails but also the inch-long, hair-thin, bright red worms called nemerteans. The fatter, fuzzier worms that look like caterpillars, with pink bellies and white bristles, which are a kind of polychaete, or bristle worm, called Archinome. And the even fatter, redder, slimier, and scalier worms. Cindy cares about all of them. We spend hours sieving and filtering the water left in the bottom of Jason's bioboxes after the rocks and creatures have been removed and then hours more picking through the resulting gunk, in the hope that not one single worm, however tiny, has escaped. All will be pickled.
Sunday, April 8, 25¡19' South, 70¡02' East A little after 4 a.m., Andy, who is piloting Jason, is trying to gather snails. The rest of us on the 4-to-8 watch are watching. Clutching a Kevlar-and-titanium scoop with Jason's claw, Andy scoops up a bunch of snails but drops the scoop. He scoops again and upends the scoop. A dozen snails cascade out in sickening slow motion. The third haul actually gets to the elevator. Later, those snails will escape as the biobox opens on its way up.
Watching this is so horrifyingly tedious, it is fascinating. The question of whether the snails will make it into the box, whether the bungee cord will extend over the corner and seal the box—all this becomes freighted with a completely disproportionate suspense. The control room becomes very quiet, 10 pairs of eyes glued to the TV monitors. It is fascinating but also very frustrating.
At today's installment of the Southwest Indian Ridge debate, Dan says: "I understand the biological imperatives. But I think everybody needs to be sanguine with the fact that we might spend the last two weeks of this cruise doing tow-yos."
Cindy says: "I've never heard a group of people so pessimistic about exploration in my life!"
Monday, April 9, 25¡19' South, 70¡02' EastCindy is quietly excited by a snail—brown, shaped like a Smurf hat, less than two inches long. It finally came up on the elevator today, along with two other kinds of snails, both of which clearly resemble species already known from the Pacific. This one is exciting because it resembles nothing Cindy has seen or heard of before. It has a massive foot that is scaly like lizard skin. People rub their fingers over it and coo. Cindy places it under the microscope for a portrait; then she rapidly dissects out tiny pieces of its mantle muscle and sulfide-blackened gill and places them in tiny aluminum-foil dishes in her drying oven. Cindy will analyze these tissues for their ratios of nitrogen and carbon isotopes. Those will help her figure out what sort of food it eats—if it eats at all. If it has symbionts, it may not need to, like Riftia, the giant tube worm.
Before Riftia was discovered off the Gal‡pagos, and before Colleen discovered symbiotic sulfur-oxidizing bacteria inside Riftia, no one knew it was possible for animals to make a living that way, completely independent of the sun. Riftia and the other hot-springs animals changed our notions about how life began on Earth and about the prospects for life on other planets.
Wednesday, April 11, 25¡19' South, 70¡02' East Yesterday the scientists finally decided to go to the Southwest Indian Ridge: "Dan got tired of repeating the same arguments," Cindy says.
But in the night the weather changed. Today the ship is rolling in 20-foot waves; a large storm is near. Jason must be brought up. What's more, we cannot recover the elevator; that requires three men in a small boat to tow the elevator back to the ship from wherever it surfaces. We will leave, abandoning the elevator on the seafloor, but we must come back and finish when the seas are calmer. That means we can't go far—the Southwest Indian Ridge is out.
The only thing to do is run up to 24¡ South and look for another vent there; tow-yos can be done in lousy weather. After all the divisive arguing, the decision was made by "the hand of God," as Dan would say later.
Sunday, April 15, 23¡24' South, 69¡12' East The penetrating smell of ethanol wafts through the main lab from where Cindy sits, decanting dollops of biobox washings into a petri dish and picking through them with tweezers under the microscope. She has spent many hours doing this. For the last four days the wind and swell have not abated.
An excited chirp the other day meant Cindy had found an aplacophoran—a wormlike, shell-less mollusk a fraction of an inch long, curved and fleshy like a grapefruit section, that is known from vents in the Pacific. This fits the overall impression Cindy has been forming of Kairei: The vents there look Atlantic, because they are swarming with shrimp, but almost all the other animals are more closely related to Pacific species. If the Indian Ocean is a highway between the other two oceans, it seems the traffic is two-way and uneven.
At breakfast that morning, the cafeteria isn't crowded; people are sleeping in. They all have time on their hands now, except for the chemists. They've been tow-yo-ing for days.
Monday, April 16, 23¡52' South, 69¡35' East The excitement began right after everyone else went to bed: The tow-yo came right down in a plume of water that was full of particles, 20 millidegrees warmer than the water around it, and a few parts per million saltier. It's the signal you'd get from an eyedropper dripping hot brine into a swimming pool, but that's what a black smoker is like. It's powerful when you're right next to it, but it gets diluted incredibly fast.
The mood on the ship has turned by 180 degrees. To top it off, the seas are at last calm enough for Jason. The plan now is to steam back to Kairei, find the elevator and finish the work, and then come back here to find and explore the new vents.
Tuesday, April 17, 25¡19' South, 70¡02' East The ship arrived back at Kairei after midnight, and Jason was promptly launched. The robot nosed around the seafloor in vain looking for the elevator. Only the anchor showed up—meaning that the elevator has drifted off while carrying $100,000 worth of gear. It is now floating somewhere in the Indian Ocean. Because it has as much as a five-day head start, in 20-knot winds and rough seas, there is no hope of finding it. Dan and his crew have begun assembling a second elevator. Another day has been lost.
As she bangs two more mussel-sampling pots into readiness, Cindy mutters, loudly and more distinctly than ever, about Jason. I ask if these ups and downs are more than one sees on the usual oceanographic cruise.
"Oh yeah," says Cindy. "Oh yeah. Big time."
Thursday, April 19, 23¡52' South, 69¡35' East We have left Kairei for good. In the end it took only one watch to do the rest of the sampling. Marv and Karen got water samples from the smokers' mouths, Colleen got some fresh, perky shrimp, and Susan got a nice chunk of chimney. When she sawed through it, the internal conduits were glittering with pyrite, or fool's gold, a form of iron sulfide. Now we're back at 24¡ South, where Bob and Marv are trying to pin down the plume, fast. Dan has been walking around patting people's backs and making the chemists coffee and generally being encouraging.
Cindy has been busy pulverizing her oven-dried animal bits with a small mortar and pestle. At the moment she is reducing Archinome, the fuzzy-wuzzy polychaete, to a beige powder. Does it not tug on her heartstrings? "These crunch really well, so it's satisfying," she says. "You do mussels and they just break and fly all over the room."
By early afternoon, the plume hunters feel they have it nailed to within a couple of hundred yards. Jason will go after it tonight.
Friday, April 20, 23¡52' South, 69¡35' East Jason found the vents last night within 45 minutes. "That was very satisfying," says Bob. This morning we are looking at an enormous convoluted wall of 60 feet high or more, a fantastic castle with crenellations and turretlike geysers gushing black smoke, the whole thing covered with shrimp. "You never get used to it," says Tim Shank, a Woods Hole biologist who specializes in vent shrimp.
Cindy was right all along, though: This site is not different from Kairei biogeographically. As you approach the vents, again you see the gathering carpet of anemones, though never as dense as at Kairei; mussels, snails, and crabs are scarcer too. Everything that's here was already at Kairei, but not everything at Kairei is here—biologically, this is a poorer site. To some of the scientists on board, that itself is an interesting fact requiring an ecological explanation. But it doesn't interest Cindy much. "It was fun for the first two minutes," she says at lunch, describing the discovery of the site. "Then we saw the shrimp."
Wednesday, April 25, 24¡28' South, 69¡53' East Jason was up for repairs last night, and some took advantage of that to watch a movie and get some sleep. Dan and Susan spent the night dredging rocks from an intriguing-looking volcano they had spotted on the sonar map 40 nautical miles south of our new vent. "We got some beautiful, fresh, glassy lava," says Susan happily. A glassy lava is one that cooled rapidly, without any elements crystallizing and separating out first. It reveals the chemical composition of the molten mantle rock that formed the seafloor in that region. If the lava is fresh—Susan can say only that it looks less than a millennium old—it could mean that eruptions are happening on that seamount right now.
Friday, April 27, 24¡30' South, 69¡54' East We've got six hours to explore the Knorr Seamount, as it is now called, before we have to head back to our vent site, finish our work there, and make for Mauritius. The seamount rises 4,900 feet above the floor of the rift valley. Jason drops down between twin volcanic peaks onto a summit plain that lies at a depth of around 7,800 feet below the surface. Within minutes the robot crosses a fissure five or 10 feet wide that disappears into the distance; we can't see the bottom. That, says Dan, is the plate boundary—the boundary between Africa and India. You could jump from one to the other here. The two plates are spreading at a rate of about two inches per year.
For the next few hours we crisscross this fissure. We cross fields of hummocky pillow lavas that are like black elephant backs. The fields are dotted with "bathtub rings" that are as wide as a few yards across, where still-hot lava has drained out from under its frozen surface, collapsing the volcanic surface. We cross ropy lava stretched into bizarre folded curtains like cake frosting. We cross corrugated sheets of lava that look like fields of wheat. At one point we see a lava flow cut by the fissure, proving that the fissure is younger. At that, Dan leaps out of his chair.
We see very little life—a couple of long, pointy-nosed fish hanging motionless just above the bottom; a few sea pens, foot-high pencils sticking up from boulders—and we never do find a vent. There is most likely one here, but we are out of time. Late in the dive we briefly chase what looks to be a giant red shrimp four to six inches long, as it swims languidly along the fissure. No one in the whole history of Earth has ever seen this place before.
Saturday, April 28, 23¡52' South, 69¡35' East "Although the driving force for this expedition was the biology, there are many, many things we don't understand about how the midocean ridge works." I have finally gotten Dan to sit down and talk into my tape recorder. "And yet it's difficult to sell these kinds of expeditions on the need to find out more about this fundamental part of the Earth. This is it—this is how the Earth's crust gets created. We have surveyed less than 1 percent of it. If you had the equivalent system on land, that would be untenable.
"One of the reasons why it is so difficult for oceanography to be in the public eye (compared with the space program) is that you can see millions of miles into space. It's tangible. You look at the ocean surface, and you can't get very far beneath it—sometimes not even a millimeter. So it's pretty tough to get somebody to understand how fantastic the surface of the Earth beneath the ocean is."
Dan is upset about lean funding for oceanography and this cruise in particular; he blames it in part for the situation between him and Cindy. He ended up organizing the cruise, he says, because someone had to do it and no one was paid to. "There's part of me that feels I should stop going to sea," he says. "I'm tired of beating my head against the wall."
At sunset, before leaving the vent site, we gather on the bow to baptize the Edmond Field, after John Edmond, a Massachusetts Institute of Technology geochemist who died while we were at sea. Edmond was in Alvin when the first hot spring was discovered off the Gal‡pagos in 1977, and both Bob and Karen did their graduate work with him. We drink port out of Styrofoam cups. Then Bob throws the empty bottle over the side.
Wednesday, May 2, Mauritius Bob and I are sitting on the terrace of the Maritim Hotel, looking out over the beach, where our shipmates are snorkeling and windsurfing, waiting for flights home. "This is the first time this has ever been done, as far as I know," he says. "Finding a vent, diving on it, and sampling it all in one cruise. This is why we had such trouble getting funded, because it was such a risk. I had this horrible feeling in my stomach before we came out here—what if we don't find anything? That was a distinct possibility."
While he was on the ship, Bob got a couple of e-mails from his dean back at Oregon State, asking him how he proposed to raise the money for his salary for the rest of the year. "The overriding piece of tension," he says, "is the funding—we all have no money. And so we're grumpy."
Tuesday, September 4 E-mail from Cindy: The long paper she wrote about the cruise, with contributions from all the participants, has been accepted by the journal Science. Its major conclusion is that the Indian Ocean vent fauna is different enough from that of other oceans to constitute a new "biogeographic province." Most of the animals are probably descended from Pacific ancestors—except for the shrimp. Tim's genetic analysis has shown that the shrimp are so close to the Atlantic species, Rimicaris, that they may in fact be that very same species. If so, then the little beasts have managed to paddle—over many generations—more than 10,000 miles from the North Atlantic to the Indian Ocean, or vice versa. No doubt they stopped at many hot springs along the South Atlantic and Southwest Indian ridges, none of which have ever been seen.
"I had hoped to find some new dominant invertebrate . . ." Cindy's e-mail says. "Why not a vent dominated by swarming isopods or benthic jellyfish? This is very telling—there is some novelty at vents, but there is enough dispersion of species on a global scale that the most successful types can be repetitive."
Still, there is hope for something really new, she says, at sections of the ridge that are more isolated—perhaps in the Arctic. There is hope as long as there are blank spaces on the map.
See the expedition for yourself on the Woods Hole Oceanographic Institution's Web site: www.divediscover.whoi.edu.