In 1983, a team of Japanese scientists on a journey through Antarctica happened upon the dwelling of a strange, strange creature.
Living in a pile of moss were tardigrades, millimeter-long animals that resembled teddy bears crossed with caterpillars.
For some reason, the scientists decided the world wasn't ready for them. So the tardigrades, and the moss they were found in, were wrapped in paper, placed in plastic baggies, and locked away in a -20 degrees Celsius freezer. There they remained — frozen and forgotten — for more than 30 years.
This sounds like the start of a horror movie. But be assured: When the tardigrades unfroze in May 2014, they did not seek vengeance upon humanity for their imprisonment.
Instead, they moseyed around on a plate of agar gel like nothing had happened. And then they reproduced.
The scientists named the two unfrozen tardigrades in the sample Sleeping Beauty 1 and Sleeping Beauty 2, and you can see them slowly come back to life in the video above.
It took a few weeks for the tardigrades to become fully reanimated. (The theory is that they needed some time to repair damage to their DNA.) Here, in the journal Cryobiology, the scientists describe Sleeping Beauty 1's slow awakening:
SB-1 [Sleeping Beauty 1] first showed slight movement in its 4th pair of legs on the first day after rehydration. This progressed to twisting of the body from day 5 along with movement in its 1st and 2nd pairs of legs, but the movements remained slow. After starting to attempt to lift itself on day 6, SB-1 started to slowly crawl on the agar surface of the culture well on day 9, and started to eat the algal food provided ... in the culture plate on day 13.
By day 21, Sleeping Beauty 1 had three eggs developing in its ovaries. On day 45, it laid 19 eggs. Fourteen of them hatched.
This is a great demonstration of the tardigrade's ability to survive almost any condition. (Amazingly, a tardigrade egg found in the Antarctic frozen moss hatched after thawing too. The scientists named this creature … Sleeping Beauty 3.)
When frozen, the animals tuck in their legs and expel all moisture from their bodies. In this state, they're called tuns. Scientists are hoping that by studying tuns, they can better understand how to preserve and heal all sorts of living tissue.
As tuns, the tardigrades produce glycerol (antifreeze), and secrete trehalose, a simple sugar with remarkable preservation properties. "Trehalose is viewed as a cocoon that traps the biomolecule inside a glassy matrix, like amber-encasing insects," explains a 2009 paper in Protein Science. When the trehalose crystalizes, the tardigrade becomes mummified in a glass suit of armor.
This process is called vitrification, and scientists have been trying to replicate it for use in protecting other delicate cellular tissues like sperm and eggs. As a tun, the tardigrade reduces its metabolism by 99.99 percent as it waits for a more suitable environment.
And the tardigrades are nothing but patient.