Cold has a way of preserving life for decades such that the latter can be reanimated given the right conditions – a distorted version of sleeping beauty, or, in this case, beast. A tardigrade has thus been brought back to life after 30 years of frozen sleep. It has even produced 14 healthy offspring. Authored by a team of researchers from National Institute of Polar Research in Japan, the paper describing the findings is published in the journal Cryobiology.
Tardigrades, also known as water bears or moss piglets, are known for their (perhaps) unrivalled ability to survive under harshly extreme conditions. Researchers from Japan have recently demonstrated their great resilience when they reanimated one that was frozen for over 3 decades.
While tardigrades are indeed characterised by this form of strength, the longest it has remained frozen before being revived was nine years. The new research is, therefore, unparalleled, as an Antarctic tardigrade (Acutuncus antarcticus) was revived.
It had been collected and frozen with another adult back in 1983 after researchers who were taking samples of moss from the Showa Station in Antarctica spotted them; they were named SB-1 and SB-2 (short for “Sleeping Beauty”). They remained in that condition for 30 years and 6 months and preserved at -20 degrees Celsius. Sadly, SB-2 died in 2014 when they were thawed; while they both displayed movement back then, the second one died because it had eaten an insufficient amount of food.
SB-1, on the other hand, experienced full recovery from the rough freezing conditions only a week after revival. From then on, it produced 19 eggs of which 14 hatched already.
Yet another miraculous aspect of the research is that an egg (SB-3) that was frozen back together with the tardigrades has also been thawed and brought forth a baby six days later. If this was not enough to prove the remarkable nature of the creature, the baby itself eventually produced its own offspring.
How was the life of the tardigrade and eggs preserved? They owe their resilience to a process called ascryptobiosis whereby all metabolism is shut down. It might not be that surprising to scientists that the organism can withstand being frozen for decades. However, being able to produce healthy babies following the frozen sleep is beyond expectations.