Scientists have discovered the first known creatures that can survive and reproduce without oxygen. The three new species from the Loricifera group were found deep in the "dead," or oxygen-free, zone of the Mediterranean Sea. One of the minuscule animals—approximately a millimeter long—looks like a jellyfish in a protective shell. "We did not think we could find any animal living there," one researcher tells the BBC. "We plan to go back and see if there are new surprises for us."
One of the species has already been officially named Spinoloricus Cinzia, after the wife of one of the Italian professors who discovered the animals. The other two, currently designated Rugiloricus and Pliciloricus, have yet to be formally described. Creatures of two of the species were discovered carrying eggs. The animals were discovered in three ocean expeditions over a decade. (Read more Mediterranean Sea stories.)