Animals revived after being in a frozen state for over 30 years: Microscopic tardigrades, also known as 'water bears,' were successfully revived and reproduced after being frozen for over 30 years.

Tardigrades (water bears) were successfully revived and reproduced after having been frozen for over 30 years. A moss sample collected in Antarctica in Nov. 1983, stored at -20°C, was thawed in May 2014. Two individuals and a separate egg retrieved from the thawed sample were revived, thereby providing the longest record of survival for tardigrades as animals or eggs. Subsequently, one of the revived tardigrades and the hatchling...

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