Prehistoric 'Frankenvirus' Mollivirus sibericum uncovered in Siberian permafrost

However, Professor Holmes said he isn't saying they're wrong: "If it is 30,000 years old, it's fantastic."
Professor Edward Holmes, University of Sydney.

Professor Edward Holmes, University of Sydney.

Viruses have traditionally been thought of as small and simple organisms. However, the discovery of the Mimivirus in 2003 means that we now know viruses can be large and complex.

Viruses are considered "giant" if they are longer than half a micron, or 0.0005 millimetres. Scientists hope that analysis of these giant viruses will help us better understand viral evolution and perhaps the origins of life itself.

Professor Holmes said that humans first studied viruses that threatened humans and economically important animals and plants. However, it is now understood that we have just "scratched the surface of the virus-sphere".

"There is an amazing diversity of viruses out there. They're in weird organisms, they're of different shapes and sizes - the giant viruses came as a real surprise - and the sea is full of them. And in most cases they have nothing to do with disease whatsoever," Professor Holmes said.

"We've just missed an amazing diversity of life. Most DNA on earth is certainly in viruses."

The discovery of a prehistoric giant virus will no doubt trigger memories for some of sci-fi thriller, The Thing, in which scientists operating in the Antarctic disturb a long-dormant, violent alien species.

Of course, M. sibericum is non-sentient, Arctic and terrestrial, so perhaps we probably don't have too much to worry about.