Wednesday, February 11, 2009

YETI CRAB (New Species)

An international team of scientists recently announced the discovery of a new species of blind deep-sea crab whose legs are covered with long, pale yellow hairs. This crab was first observed in March 2005 by marine biologists using the research submarine Alvin to explore hydrothermal vents along the Pacific-Antarctic ridge, south of Easter Island. Because of its hairy legs, this animal was nicknamed the "Yeti crab," after the fabled Yeti, the abominable snowman of the Himalayas. The Yeti crab was discovered during the Easter Microplate expedition to the southeast Pacific, led by MBARI scientist Bob Vrijenhoek. The primary goal of this expedition was to learn how bottom-dwelling animals from one deep-sea hydrothermal vent are able to colonize other hydrothermal vents hundreds or thousands of miles away. Vrijenhoek and his team were addressing this question by comparing the DNA of animals at hydrothermal vents in different parts of the Pacific Ocean.

During one Alvin dive, marine biologist Michel Segonzac, from Institut français de recherche pour l'exploitation de la mer (IFREMER) in France, noticed an unusually large (15-cm-long) crab with hairy arms lurking on the seafloor. Segonzac asked the Alvin pilots to collect this crab and bring it back to the surface.

The researchers saw more of these unusual crabs during subsequent Alvin dives. Most of the crabs were living at depths of about 2,200 meters (7,200 feet) on recent lava flows and areas where warm water was seeping out of the sea floor. According MBARI biologist Joe Jones, "Many of the crabs were hiding underneath or behind rocks—all we could see were the tips of their arms sticking out."

After returning to shore, researchers Segonzac and Jones worked with Enrique Macpherson from the Consejo Superior de Investigaciones Científicas (CSIC) in Spain to identify the crab they had collected. They found that the crab was not only a new species (which they named Kiwa hirsuta), but an entirely new family (Kiwaidae). The Yeti crab is a distant relative to the hermit crabs commonly seen lurking in tide pools.