24,000-year-old organisms found frozen in Siberia can still reproduce
A microscopic worm-like creature, labelled an "Evolutionary scandal" by biologists for having thrived for millions of years without having sex, has now been shown to persist for at least 24,000 years in Siberian permafrost and then reproduce, researchers have found. The Soil Cryology Lab has previously isolated other microscopic organisms - including a 30,000-year-old nematode worm - from permafrost. In this study, Malavin and his colleagues used radiocarbon-dating to determine that the rotifers, recovered from samples salvaged from remote Arctic locations via a drilling rig, were about 24,000 years old. The rotifers found in the permafrost would have been under the feet of big woolly creatures - such as the woolly rhino - that are now extinct, Malavin noted. The scientists are uncertain about the biological mechanisms that allow these tiny organisms to survive in ice for such a protracted period, said Malavin. These rotifers, together with other organisms found in the permafrost, represent a result of a big natural experiment that we can't replicate so they are good models to study further," said Malavin. Matthew Cobb, a professor of zoology at the University of Manchester who was not involved in the research, said the most spectacular implication of the research was that there may be all sorts of animals frozen in the permafrost that could awake as global warming melts the permafrost.