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The Strange Crab Hairy Chest

This species “Yeti”, humorously nicknamed in honor of David Hasselhoff, live in extreme conditions, without electricity and almost no oxygen in the deep ocean.

A crab ‘Hoff’ Indian Ocean

Crabs ‘Hoff’ in a vent

The crab hairy chest dubbed “Hoff” in honor of the actor David Hasselhoff, in a time so inclined to teach the pectoral is a strange creature recently discovered that, because of their rarity, not knew where it came from. Dweller hydrothermal vents deep in the Southern Ocean and the Indian, the origins of this animal proved a mystery. Now a team of scientists from the University of Oxford has made ​​a genetic study showing that this crab Yeti (Kiwaidae) is not an abandoned relic in deep water, but, in evolutionary terms, a newcomer, since branched out for 40 million years.

The crabs ‘Hoff’, which have not yet been scientifically described and are probably two different species, separated from their cousins ​​Yeti hairy claws and divided east on Pacific ocean ridges, through the Drake Passage between South America and Antarctica, reaching the vents in the Southern Ocean and India.

The Hoff live in one of the most extreme environments on the planet, more than 2,000 meters under the sea, where volcanic vents overheated water to 380 degrees Celsius and expel harmful chemicals. There is very little oxygen and light. They feed on bacteria ‘grown’ in their hairy chests effectively. Then catch them with special mouthparts as combs with which strain bacteria to devour.

“Cooked alive”

However, despite their resistance, new research shows that their precarious lifestyle could leave the ‘Hoff’ vulnerable to changes in oxygen levels in the oceans caused by global warming. The crab has to be placed close enough vents for food, “but not at risk of choking or being cooked alive,” says Nicolai Roterman, Department of Zoology, University of Oxford.

It was once thought that (unlike the inhabitants of the land or shallow sea) creatures that live around deep-sea vents might be immune to the effects of extreme weather changes, to the extent that bacteria that feed would not be affected by weather patterns from the surface. However, a reassessment of the age of the animals that live in these habitats suggests that, far from being old ‘relics’ most vent species diversified in the last 55 million years. The reasons are unclear, but a period of intense global warming spanning several million years and that drastically reduced oxygen levels in deep waters worldwide may be the culprit.

The relatively recent origins Yeti crabs seem to confirm that the inhabitants of the deep sea vents may disappear and vents periodically repopulated only by a wave of new species when conditions become favorable again. Scientists believe that during episodes of extreme global warming, circulation between well-oxygenated surface waters and deeper will decrease, leading to the gradual decrease of oxygen in the deep sea.

In these circumstances, Yeti crabs and other creatures so special may be doomed to extinction. With less oxygen available now, would face the difficult choice of “suffocate or starve.”

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