TOKYO, Feb. 16 (UPI) -- Microscopic tardigrades, or "water bears," have successfully reproduced after emerging from 30 years frozen in an Antarctic moss sample.
The tiny creatures' revival after three decades in frozen moss is a new record, and the resumption of reproductive abilities is a first.
Researchers in Japan say the findings will offer new insights into tardigrades' cryptobiosis abilities -- the species' ability to temporarily shut down metabolic activity in response to external changes, like cold temperatures.
The moss sample was collected in 1983. In May 2014, it was defrosted and submerged in water.
From the thawed moss sample, scientists successfully extracted two water bears and one egg. The egg was reared in the lab, fueled by algae food. Both the newly hatched tardigrade and one of the two revived from the frozen moss went on to continually reproduce.
Though it took several days to resume full activity and its eggs required a longer incubation period, the revived and reproductive tardigrade went on to lay 19 eggs within a few weeks -- 14 of which successfully hatched.
"Our team now aims at unraveling the mechanisms underlying the long-term survival of cryptobiotic organisms by studying damage to tardigrades' DNA and their ability to repair it." Megumu Tsujimto, the lead researcher at National Institute of Polar Research, said in a press release.
The new findings were published in the journal Cryobiology.
Previous studies have looked at the basic revival abilities -- eating and crawling -- after as long as 9 years spent frozen, but this was the first time scientists studied post-thaw reproduction.