June 19, 2013
New Research Reveals Origin Of Hoff Yeti Crab
[WATCH VIDEO: Uncovering History of Yeti Crabs]
Michael Harper for redOrbit.com — Your Universe OnlineFor all we know about the natural world, scientists are still finding new creatures and species living in the farthest corners of earth. Just last year, for instance, oceanographers from the University of Oxford and University of Southampton discovered a species of yeti crab covering hydrothermal vents more than a mile below the Southern Ocean.
These crabs, later nicknamed “The Hoff” due to their hairy chest, live in one of the most extreme environments in the world, complete with deadly chemicals, high heat, and a thinning edge of available oxygen. The University of Oxford now says it has unraveled the origins of the 'Knight Rider' actor's namesake in the first report of this creature´s genetic makeup. This report is published in the journal Proceedings of the Royal Society B.
The University of Oxford report suggests the Hoff Crab may very well be a separate species than the Yeti, perhaps distantly separated cousins. Though it traces the genetic origins back to about 40 million years ago, the report calls these crabs “relative newcomers” to the animal kingdom.
When the Hoff crab split away from its Yeti cousins, they headed east from the Pacific Ocean, across the Drake Passage and into the vents of the Southern and Indian Oceans. Here, the Hoff crabs have a delicate balancing act of a life in extreme conditions.
At 1.24 miles below the surface, light does not exist and oxygen is incredibly thin. In addition to the dark, anoxic conditions and high pressure of the sea floor, underwater vents are spewing out noxious chemicals and warming the water to temperatures over 700 degrees Fahrenheit.
Here, the Hoff crabs cluster and rest patiently, using their hairy chests as a breeding ground for bacteria. Once enough bacteria are gathered, they use comb-like mouth parts to eat them.
Like all other deep-sea creatures, the near absence of oxygen is something the Hoff crab has grown accustomed to.
“They need oxygen to survive, which is in short supply around the vents, but the bacteria they ℠farm´ for food depend on chemicals only available near the vents,” said Roterman, who bestowed upon these crabs the nickname of “the Hoff.”
“They exist in the narrow zone where the water from the vents and normal seawater mixes; their challenge is to position themselves close enough to the vents to thrive but not so close that they risk suffocating or getting cooked alive,” he added.
It had been previously understood that sea floor-dwelling creatures may be immune to the changes brought on by global warming, but recent studies have questioned this assumption.
According to the Southampton and Oxford researchers, the effects of global warming, which place the Hoff crab in danger, may have been exactly what brought them into existence all those millions of years ago.
Though they don´t know exactly what happened, the researchers assume a shift in oxygen associated with global warming some 55 million years ago may have wiped out previous vent dwellers, making room for the Yeti Crab to take hold.
“Yeti crabs and other such creatures may in fact be especially prone to extinction when there is less oxygen available in the deep ocean,” said Roterman. “They would face the stark choice of ℠suffocate or starve´.”