For all those believers out there, the search is over. The elusive yeti has finally been found — at least, the crab version. Scientists have discovered a third species of the yeti crab, known as Kiwa tyleri, living 8,500 feet below the surface in the waters off Antarctica in one of the harshest environments imaginable.
This blind white hairy-armed yeti crab, found to range in size from under an inch to around six inches in length, requires very specific conditions to live. So specific, and so uninhabitable for other creatures that scientists had to rely on a nifty piece of technology to obtain their research.
By controlling a remote-operated vehicle, researchers were able to go reach the hydrothermal vents of East Scotia Ridge and bring a few specimens back to the surface for further study.
The crabs live in a zone sandwiched between the extremely cold water that hovers just above freezing and the hydrothermal vents that emit water that can reach temperatures of more than 700 degrees Fahrenheit. They can't take the extreme cold or the extreme heat, so they live in that little pocket between, making their habitable space small and very specific. If they go too far into the cold or too far into the hot water, they die.
"We knew immediately that we'd found something tremendously novel and unique in hydrothermal vent research," said study leader Sven Thatje, an ecologist at the University of Southampton.
Because the yeti crab's habitat is so limited, they cluster together. Thatje described the crabs as "like beans in a jar, filling every available space." In fact, they found that around 700 individuals could occupy the same 11 square feet of space.
A mob of yeti crabs cover a hydrothermal vent in an effort to survive the harshness of the deep ocean floor. (Photo: PLOS One)
Unlike the males, the females don't always get to stay in that safety zone. Scientists speculate that some females went to the colder water to successfully lay their eggs. This isn't easy on the brooding mothers, according to the study, because they often can be seen with a deteriorated shell and highly worn setae, meaning that the bristly hair-like substance on their arms and chest shows damage.
And the news just gets worse for the females. "Females that move off-site do not feed; in fact, they starve," said Thatje. The researcher believes that once the females leave the warmth of the vents, they never make it back, lacking the strength to return to the group.
Since the crustaceans live so far below the surface, they can't access the sun like so many other species. Instead, they have to create their own food by growing bacteria on their setae, showing that those hairy arms aren't just ornamental. They are an integral part of the crab's design.
And, breaking tradition from their two relatives, the Kiwa puravida and K. hirsute, this new type of yeti crab also grow setae on their chests, prompting the researchers to playfully nickname the kiwa tyleri "the Hoff crab," referring to "Baywatch" star David Hasselhoff, who was famous for showing off his hairy chest.
The chest setae likely enable the crab to grab bacteria from the vent chimneys.
LiveScience notes that another adaption discussed in the study is the spikes on the end of the crabs' legs, helping them to be more effective climbers. Thatje explained, "This is a significant advance in its evolution, and differentiates it from the other known yeti crabs, which clearly do not possess the ability to climb vent chimneys."
More research is still being done to learn about the yeti crabs, which up until 2005 were still unknown to humans. It’s possible that more species exist, and it's certain that more information can be learned about the species scientists have already identified.
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