Image: Yeti crab
(c) NERC ChEsSo Consortium
A new species of yeti crab piles around the hydrothermal vents in Antarctica. The vents may be a safe haven for the crabs.
By LiveScience senior writer
updated 1/3/2012 8:10:43 PM ET 2012-01-04T01:10:43

Scientists doing their first exploring of deep-sea vents in the Antarctic have uncovered a world unlike anything found around other hydrothermal vents, one populated by new species of anemones, predatory sea stars, and piles of hairy-chested yeti crabs.

It was "almost like a sight from another planet," said expedition leader Alex Rogers, a professor of zoology at Oxford University. 

  1. Science news from NBCNews.com
    1. NOAA
      Cosmic rays may spark Earth's lightning

      All lightning on Earth may have its roots in space, new research suggests.

    2. How our brains can track a 100 mph pitch
    3. Moth found to have ultrasonic hearing
    4. Quantum network could secure Internet

Even in the eye-popping world of deep-sea vents, the Antarctic discoveries stand out, with the unfamiliar species of crabs found crowded in piles around the warm waters emanating from the seafloor. Many of the animals found at the vents have never been found at hydrothermal vents in other oceans, Rogers said. "To see these animals in such huge densities was just amazing," Rogers told LiveScience.

In the dayless world of deep-sea vents, energy comes not from the sun but from the hydrothermal energy generated in the oceanic crust.

The yeti crabs seem to cultivate "gardens" of bacteria on their chests, which are covered with hairy tendrils. These bacterial mats almost certainly provides the crabs with sustenance, Rogers said. In turn, predatory seven-armed sea stars stalk the periphery of the vents, snacking on unfortunate crabs. [See video and photos from the vents]

"We were absolutely stunned to see the animal communities, because they were so different from the hydrothermal vents seen elsewhere," Rogers told LiveScience. He and his colleagues reported their results Jan. 3 in the journal PLoS Biology.

Discovery in the deep sea
Weird life flourishes at deep-sea vents the world over, but no one had ever found hydrothermal vents in Antarctica, explained Jon Copley, a professor of earth and ocean science at the University of Southampton who also participated in the research. That's largely because it's more difficult to do research in the harsh Southern Ocean than in temperate climes. [ Extremophiles: World's Weirdest Life ]

"It's only quite recently that we've been able to be bold enough, really, to head to the poles," Copley told LiveScience.

In 1999, Antarctic mapping surveys turned up hints of hydrothermal vent output in the water column over the East Scotia Ridge in the Atlantic section of the Southern Ocean, between Antarctica and South America and eastward. It took 10 years for researchers to get back for a full-blown expedition, during which they lowered cameras to two areas, 8,530 feet and 7,874 feet deep, catching the first glimpses of Antarctic hydrothermal vents. Among them were "black smokers," chimney-like vents that emit dark-hued, superheated water.

Although the background temperature of the Southern Ocean in the area is 32 degrees Fahrenheit, the black smokers gushed water as hot as 721 degrees F.

In 2010, the researchers returned with a remote-operated submersible vehicle (ROV) called Isis. The sub took close-up photos of the amazing vent fauna and collected samples of organisms for identification.

New world
Among the new species were the yeti crabs, crowded around the vents up to 600 per square meter.

"They're literally, in places, heaped up upon each other," Rogers said. Crabs normally don't tolerate cold temperatures well, so the vents may be a warm haven for these crabs, Copley said.

Image: Pale octopus
Oxford University
The expedition spotted this pale octopus on the Antarctic seafloor.

Unlike vents in other oceans, the Antarctic vents lack tube worms, mussels and shrimp. Instead they harbor new species of barnacles and anemones, as well as a large brown spiral-shelled snail. The researchers even saw ghost-pale octopuses, which seemed drawn to the lights of the ROV.

"We were completely blown away by what we found," Copley said. "I've worked at vents in the Atlantic, the Pacific and the Indian Ocean, but these are the lushest, richest vents, in terms of life, that I've come across."

The discovery helps fill a gap in researchers' understanding of how deep-sea life disperses around the oceans, Rogers said. They had expected that the Southern Ocean would be a historical gateway for vent species to travel between the Atlantic, Pacific and Indian oceans, and there do seem to be some species, such as the yeti crab, that are related to species found at other vents. Those relationships seem to reach back into geological history, Copley said, when there was a connection between the Antarctic and the eastern Pacific.

But the vast differences between Antarctic vents and vents found elsewhere suggest that the area is not a gateway but a biological region in its own right, Rogers said. The cold Antarctic waters may act as a barrier to species that start their lives as swimming, feeding larvae, he said. On the other hand, larvae that carry their own food supply with them in eggs — known as lecithotrophic larvae — may be able to survive and disperse in the chilly Southern Ocean.

As humans increasingly exploit the deep seas for fish, oil and mining, understanding how species are dispersed is crucial, Copley said.

"Until we understand what governs the patterns of life at deep-sea vents, how interconnected their populations, how well life disperses from vent to vent, we can't make responsible decisions about how to manage these deep-ocean resources."

You can follow LiveScience senior writer Stephanie Pappas on Twitter @sipappas. Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on Facebook.

© 2012 LiveScience.com. All rights reserved.

Explainer: Top 10 oddballs of the animal world

  • Image: Platypus
    Healesville Sanctuary

    From the outside, the platypus looks like a grade-school art project assembled by a kid too busy making spitballs to pay attention in class. The creature, which is classified as a mammal, has a duck's bill and webbed feet, lays eggs like a reptile, but has fur and rears its young on milk.

    Researchers say the platypus genome is equally cobbled together from bird, reptile and mammalian lineages. One more oddity: Males can deliver venom from tiny spurs on each hind limb. Click on the "Next" arrow above to learn about nine more oddballs in the animal world.

    More info: Mixed-up platypus genome unscrambled

    — By John Roach, msnbc.com contributor

  • Colossal squid has plate-sized eye

    AP

    In April 2008, scientists in New Zealand looked a thawing colossal squid in the eye and discovered that the eye is, well, colossal — about the size of a dinner plate. That makes it the largest animal eye on Earth. Fishermen caught the 1,000-pound creature last year in Antarctic waters and froze it intact for scientific study. Colossal squids can reach 46 feet in length and have tentacles equipped with suckers and hooks. Scientists believe the creatures can descend to 6,500 feet and are active, aggressive hunters.

    More info: Huge squid caught, could be biggest ever

  • Aye-aye gives grubs the finger

    Duke University Lemur Center

    The aye-aye is a bushy-tailed primate from Madagascar with big eyes and bat ears. But call it funny-looking and it just might extend its extra-long middle finger in your general direction. The member of the lemur family otherwise uses the extended digit to fish out grubs from the crevices of trees. Captive aye-ayes such as the one shown here from Duke University are teaching scientists about the evolution of color vision.

    Learn more about the brainiac of all lemurs

  • Star-nosed mole sniffs out food, fast

    Image: Star-nosed mole
    Kenneth C. Catania / Vanderbilt

    The fleshy appendages that ring the snout of the star-nosed mole, shown here, make it one strange-looking creature. But when it comes to eating, those 22 tentacles help the mole detect and devour food faster than the human eye can follow — in a fraction of a second. Researchers say the speedy feeding allows the mole to prey on small insect larvae that would otherwise be too energetically costly to eat. The creature lives and forages under the cover of marshes and wetlands along the east coast of North America.

  • Burrowing toad is genetically different

    Robert Puschendorf

    For an amphibian, the stocky and squat Mexican burrowing toad doesn't look all that strange, but it's actually unique. A global conservation program called EDGE of Existence ranks the toad as the most "evolutionarily distinct" amphibian in the world. A fruit bat, polar bear, killer whale, kangaroo and human are all more closely related to one another than the toad is to any other species, according to the program. The Mexican burrowing toad, as its name suggests, spends most of the year underground, coming out only after particularly heavy rains to breed in pools of water.

    Learn about other bizarre amphibians under threat

  • Yeti crab lurks on the ocean bottom

    A Fifis  /  AP

    Named after the legendary shaggy man-beast that tromps through the snows in some of the world's tallest mountains, the Yeti crab blindly scurries about hydrothermal vents along a ridge at the bottom of the Pacific Ocean. First observed in 2005, the crab, officially named Kiwa hirsute, sports a carpet of pale yellow hairs on its arms. Scientists suspect the crab uses those hairs either to farm bacteria or to feel its way around the seafloor for food and potential mates.

    More info: Scientists to list all species on Web

  • Narwhals, the 'unicorn' whales

    Glenn Williams / Harvard Medical School

    Unicorns are purely mythical creatures, but the myths may have been inspired by narwhals. Most males and some females among the 2,200- to 3,500-pound whales sport an 8-foot-long appendage that emerges from the left side of their upper jaw. Scientists recently discovered that the elongated tooth is packed with nerve endings, making it extraordinarily sensitive. The whales may use it to determine the salinity of water and search for food. Male narwhals are also known to rub their tusks together, presumably because it gives off a unique sensation.

    More info: Mystery of 'unicorn' whale solved

  • Sucker-footed bats stick to Madagascar

    Field Museum (left); Bat Conservation Int'l (right)

    In January 2007, scientists announced the discovery of a new species of bat that uses suckers on its thumbs and hind feet to stick to broad-leafed plants such as the traveler's palm. The new species, Myzopoda schliemanni (left image), was found on the dry, western side of the African island nation of Madagascar and is closely related to another sucker-footed bat called Myzopoda aurita (right image) that lives in the humid eastern forests. Conservationists were heartened by the discovery because it suggests the bats can adapt to pioneering broad-leafed plants in deforested areas. Only about 8 percent of the island's original forest cover remains.

    Watch NBC video: What's killing all the bats?

  • Long-eared jerboa hops onto the screen

    Image: Long-eared jerboa
    ZSL

    In December 2007, conservationists released the first known footage of an endangered rodent they've nicknamed the "Mickey Mouse of the Desert." Known more formally as the long-eared jerboa, the little critter has ears about one-third larger than its head, and legs that allow for hopping like a kangaroo. The International Union for Conservation of Nature lists the species as endangered. One threat: the domestic cat.

    More info: Mongolian 'Mickey Mouse' caught on tape

  • Ligers, wholphins and grolar bears, oh my!

    Image: Liger
    TODAY show

    Every now and again, trysts between two different species result in oddball offspring that capture the public's fascination. Ligers, which are a cross between a male lion and a female tiger, were immortalized in the 2004 cult movie "Napoleon Dynamite": The main character of the 2004 cult movie, played by Jon Heder, describes it as "pretty much my favorite animal." (A real one is shown above.) Other popular hybrids include wholphins, which are a cross between false killer whales and Atlantic bottlenose dolphins; and the "grolar bear," a cross between a grizzly bear and polar bear.

    Watch NBC video of a liger
    Whale-dolphin hybrid has baby wholphin
    Hairy hybrid: Half grizzly, half polar bear

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments