Frozen for thirty-two thousand years, and blossoming again, all thanks to squirrels

Full flowering plants have been created from Siberian  fruit seeds stored by squirrels thousands of years ago.

In an experiment which received world wide attention, researchers Svetlana Yashina and David Gilichinsky of the Russian Academy of Sciences brought the ancient herbaceous Silene Stenophylla back to life in a laboratory near Moscow.

Details were revealed in February in the  Proceedings of the National Academy of Sciences.

The plants were grown after the discovery of 70 squirrel hibernation burrows along the bank of the lower Kolyma river, in northeast Siberia, with thousands of seed samples from various plants.

'All burrows were found at depths of 20 to 40 metres (65 to 130 feet) from the present day surface and located in layers containing bones of large mammals such as the mammoth, woolly rhinoceros, bison, horse, deer, and other representatives of fauna' from the Late Pleistocene Age.

The key to their survival over almost 32,000 years was that the burrows were quickly covered with ice.

They have remained encased and protected by the permafrost since then, as if kept in a household freezer.

While the scientists were unsuccessful in using seeds to grow plants, they used instead elements of the plant's fruit which they describe as 'placental tissue' to successfully grow regenerated plants.

Prior to this pioneering work, the previous record for viable regeneration of ancient flora was with 2,000-year-old date palm seeds near the Dead Sea in Israel.

GThe research could be the first of many experiments to bring back life that had assumed to be extinct yet in fact can be recovered from the permafrost.

They highlight the importance of permafrost in the 'search of an ancient genetic pool, that of preexisting life, which hypothetically has long since vanished from the earth's surface'.