OREANDA-NEWS  The researchers analyzed ice cores taken in 2015 from the Guliya Ice Cap in western China. The cores contain layers of ice that accumulate year after year and hold everything in the atmosphere at that time. Thus, the layers represent a kind of timeline that scientists use to track changes in climate, microbes, viruses and atmospheric gases in the past. The ice samples were about 15 thousand years old.

It turned out that the ice contains the genetic material of 33 viruses. The existence of four of them was already known to science, but 28 were discovered for the first time. Moreover, about half of the viruses survived due to freezing. According to scientists, viruses are adapted to cold conditions and are able to infect cells at low temperatures. However, they are most likely safe for animals and humans and infect plants.

Earlier it was reported that Russian scientists, together with colleagues from Denmark, Great Britain and Sweden, discovered the most ancient evidence of human infection with viruses in Siberia. Researchers obtained the first direct evidence that early modern humans suffered from herpesviruses and adenoviruses, which originated several hundred thousand years ago and have been circulating in the human population since at least the Pleistocene.