Animals Frozen For 3 Decades Brought Back To Life

In what seems to be an oddity only common to the likes of captain Steve Rogers, microscopic animals that were frozen for more than 30 years were thawed, successfully revived – and even reproduced.

Antartic tardigrades, microscopic animals that are also known as water bears or moss piglets as reported by The Huffington Post, were acquired from a frozen moss sample taken from Antarctica in 1983. The results of the study are published in the journal Cryobiology.

The researchers, from the National Institute of Polar Research in Tokyo, Japan, thawed and revived two of the 1mm-long animals, the Asahi Shimbun newspaper reported. Although one of them died 20 days into the experiment, the other laid 19 eggs, 14 of which successfully hatched into tardigrade offspring.

A tardigrade egg that was collected with the other samples also successfully hatched, and the water bear that came from it successfully laid 15 eggs of its own. Seven of these eggs successfully hatched.

"We recorded recovery of two individuals and development of a separate egg of the Antarctic tardigrade, Acutuncus antarcticus, providing the longest records of survival for tardigrades as animals or eggs," the researchers report, as per Science Alert.

This achievement marks a new record for the eight-legged, segmented critters. The longest survival rate for a tardigrade that was previously recorded was at nine years, while this one spans three decades. Although the study happened in 2014, the results were only published recently.

Tardigrades, according to Gizmodo, are tiny water-dwelling critters capable of withstanding some of the most severe environmental conditions. These conditions include total dehydration, freezing, radiation and the vacuum of space.

This is largely brought about by the tardigrades' extraordinary genome, nearly 18% of which is composed of DNA from other organisms, including plants, fungi, bacteria and viruses.

Tardigrades, according to the BBC, are able to enter a process known as cryptobiosis, which is characterized by a slowing down of their metabolism until it practically shuts down. This enables the creatures to withstand freezing temperatures.

Megumu Tsujimoto, lead researcher for the study, said that they now want to "unravel the mechanism for long-term survival by looking into damage to tardigrades' DNA and their ability to repair it."

Although this new finding is a remarkable feat, the longest survival rate recorded is that of the plant-parasitic nematode worm, Tylenchus polyhypnus. It was able to survive 39 years in a frozen state.

Following is another nematode, a second-stage larva of Anguina triciti, which survived 32 years.