Permafrost, soil or underwater sediment that has remained below freezing for over two years, covers 15% of the Northern Hemisphere and 11% of the global surface. The permafrost has preserved many secrets and acted as a natural time capsule. As permafrost melts, remarkable finds have been unearthed, including extinct horses, nematodes, and a step bison. One of the most exciting discoveries was an almost-pristine extinct horse that was only two weeks old when it died.

The specimen still had its skin, tail, hooves, and hair, and researchers found liquid blood, which is very rare in permafrost animals. The baby horse was dated to about 42,000 years ago, making it the oldest specimen with liquid blood, sparking excitement that the blood could be used to clone the animal. Similarly, a nematode, a microscopic worm, was found in permafrost and was dated back to the Pine, around 42,000 years ago.

The nematode was able to come back to life through cryptobiosis, a physiological state in which metabolic activity is reduced to an undetectable level without stopping altogether. The specimen surprised researchers as it not only came back to life but also started reproducing.