Friends,
This happened because a squirrel did what needed to be done. This is a wonderful story.
Kagiso, Max
Dead for 32,000 Years, an Arctic Plant Is Revived
By NICHOLAS WADE
This would be the oldest plant by far that has ever been grown from ancient tissue. The present record is held by a date palm grown from a seed some 2,000 years old that was recovered from the ancient fortress of Masada in
Seeds and certain cells can last a long term under the right conditions, but many claims of extreme longevity have failed on closer examination, and biologists are likely to greet this claim, too, with reserve until it can be independently confirmed. Tales of wheat grown from seeds in the tombs of the pharaohs have long been discredited. Lupines were germinated from seeds in a 10,000-year-old lemming burrow found by a gold miner in the
Despite this unpromising background, the new claim is supported by a firm radiocarbon date. A similar avenue of inquiry into the deep past, the field of ancient DNA, was at first discredited after claims of retrieving dinosaur DNA proved erroneous, but with improved methods has produced spectacular results like the reconstitution of the Neanderthal genome.
The new report is by a team led by Svetlana Yashina and David Gilichinsky of the
“This is an amazing breakthrough,” said Grant Zazula of the Yukon Paleontology Program at
But the Russians’ extraordinary report is likely to provoke calls for more proof. “It’s beyond the bounds of what we’d expect,” said Alastair Murdoch, an expert on seed viability at the
The Russian researchers excavated ancient squirrel burrows exposed on the bank of the lower
Some of the storage chambers in the burrows contain more than 600,000 seeds and fruits. Many are from a species that most closely resembles a plant found today, the narrow-leafed campion (Silene stenophylla).
Working with a burrow from the site called Duvanny Yar, the Russian researchers tried to germinate the campion seeds, but failed. They then took cells from the placenta, the organ in the fruit that produces the seeds. They thawed out the cells and grew them in culture dishes into whole plants.
Many plants can be propagated from a single adult cell, and this cloning procedure worked with three of the placentas, the Russian researchers report. They grew 36 ancient plants, which appeared identical to the present day narrow-leafed campion until they flowered, when they produced narrower and more splayed-out petals. Seeds from the ancient plants germinated with 100 percent success, compared with 90 percent for seeds from living campions.
The Russian team says it obtained a radiocarbon date of 31,800 years from seeds attached to the same placenta from which the living plants were propagated.
The researchers suggest that special circumstances may have contributed to the remarkable longevity of the campion plant cells. Squirrels construct their larders next to permafrost to keep seeds cool during the arctic summers, so the fruits would have been chilled from the start. The fruit’s placenta contains high levels of sucrose and phenols, which are good antifreeze agents.
The Russians measured the ground radioactivity at the site, which can damage DNA, and say the amount of gamma radiation the campion fruit accumulated over 30,000 years is not much higher than that reported for a 1,300-year-old sacred lotus seed, from which a plant was successfully germinated.
The Russian article was edited by Buford Price of the
Tragedy has now struck the Russian team. Dr. Gilichinksy, its leader, was hospitalized with an asthma attack and unable to respond to questions, his daughter
Eske Willerslev, an expert on ancient DNA at the
If the ancient campions are the ancestors of the living plants, this family relationship should be evident in their DNA. Dr. Willerslev said that the Russian researchers should analyze the DNA of their specimens and prove that this is the case. However, this is not easy to do with plants whose genetics are not well studied, Dr. Willerslev said.
If the claim is true, then scientists should be able to study evolution in real time by comparing the ancient and living campions. Possibly other ancient species can be resurrected from the permafrost, including plants that have long been extinct.
This article has been revised to reflect the following correction:
Correction: February 21, 2012
An earlier version of this article misidentified the organization with which Ann Griswold is affiliated. She is a spokeswoman for the journal Proceedings of the
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"The master class has always declared the wars; the subject class has always fought the battles. The master class has had all to gain and nothing to lose, while the subject class has had nothing to gain and everything to lose--especially their lives." Eugene Victor Debs
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