Longest time survived frozen in ice by a tardigrade

On 25 December 2015, scientists from Japan’s National Institute for Polar Research announced that they had successfully revived two tardigrades that had been frozen in water ice since November 1983. The two tardigrades, also known as "water bears" owing to their appearance, were thawed in March 2014. The two adult tardigrades, nicknamed SB-1 and SB-2 (short for Sleeping Beauty), began moving after defrosting.

SB-2 soon died after defrosting but SB-1, which showed slight movement on the first day of defrosting, was able to eat algal food by day 13. It then laid 19 eggs, 14 of which hatched with no health problems evident in the offspring. Tardigrades exist in the fossil record as far back as 500 million years and are well known for being one of the hardiest creatures on Earth.