Scientists discover animals that live without oxygen

Washington, April 8 (ANI): Animals that live their entire lives without oxygen and surrounded by 'poisonous' sulphides have been discovered for the first time, deep under the Mediterranean Sea.

Roberto Danovaro, from the Polytechnic University of Marche, Ancona, Italy, and his colleagues say that the existence of multicellular organisms (new members of the group Loricifera), shows that they are alive, metabolically active, and apparently reproducing in spite of a complete absence of oxygen.

During the study, the researchers retrieved sediment samples from a deep hypersaline anoxic basin (DHABs) of the Mediterranean Sea and studied them for signs of life.

"These extreme environments have been thought to be exclusively inhabited by viruses, Bacteria and Archaea. The bodies of multicellular animals have previously been discovered, but were thought to have sunk there from upper, oxygenated, waters. Our results indicate that the animals we recovered were alive. Some, in fact, also contained eggs," said Danovaro.

Electronmicroscopy shows that instead of aerobic mitochondria, these animals possess organelles resembling the hydrogenosomes found previously in unicellular organisms (protozoans) that inhabit anaerobic environments.

According to Lisa Levin of the Scripps Institution of Oceanography, the implications of this finding may reach far beyond the darker parts of the Mediterranean Sea floor.

The research appears in the open access journal BMC Biology. (ANI)