Flowers regenerated from 30,000-year-old frozen fruits, buried by ancient squirrels

By Ed Yong | February 20, 2012 3:00 pm

Fruits in my fruit bowl tend to rot into a mulchy mess after a couple of weeks. Fruits that are chilled in permanent Siberian ice fare rather better. After more than 30,000 years, and some care from Russian scientists, some ancient fruits have produced this delicate white flower.

These regenerated plants, rising like wintry Phoenixes from the Russian ice, are still viable. They produce their own seeds and, after a 30,000-year hiatus, can continue their family line.

The plant owes its miraculous resurrection to a team of scientists led by David Gilichinsky, and an enterprising ground squirrel. Back in the Upper Pleistocene, the squirrel buried the plant’s fruit in the banks of the Kolyma River. They froze.

Over millennia, the squirrel’s burrow fossilised and was buried under increasing layers of ice. The plants within were kept at a nippy -7 degrees Celsius, surrounded by permanently frozen soil and the petrifying bones of mammoths and woolly rhinos. They never thawed. They weren’t disturbed. By the time they were found and defrosted by scientists, they had been buried to a depth of 38 metres, and frozen for around 31,800 years.

People have grown plants from ancient seeds before. In 2008, Israeli scientists resurrected an aptly named Phoenix palm from seeds that had been buried in the 1st century. But those seeds were a mere 2,000 years old. Those of the new Russian flower – Silene stenophylla – are older by an order of magnitude. They trump all past record-holders.

Svetlana Yashina from the Russian Academy of Sciences grew the plants from immature fruits recovered from the burrow. She extracted their placentas – the structure that the seeds attach to – and bathed them in a brew of sugars, vitamins and growth factors. From these tissues, roots and shoots emerged.

Yashina potted the plants and two years later, they developed flowers. She fertilised the ancient flowers with each other’s pollen, and in a few months, they had produced their own seeds and fruits, all viable. The frozen plants, blooming again after millennia in the freezer, seeded a new generation.

S.stenophylla is still around, but Yashina found that the ancient plants are subtly different to their modern counterparts, even those taken from the same region. They’re slower to grow roots, they produce more buds, and their flower petals were wider.

This is the first time that anyone has grown plants from seeds tissue deeply buried within permanently frozen burrows. But it’s not the first time that someone has tried. In 1967, Canadian scientists claimed that they had regenerated Arctic lupin from 10,000 year old seeds that had been buried by lemmings. But in 2009, another team dated those same seeds and found that they were actually modern ones, which had contaminated the ancient sample.

Mindful of this mistake, Yashina carefully checked that her plants were indeed ancient ones. She dated the seeds directly, and her results matched age estimates from other samples from the same burrow. The burrows have been buried well below the level that animals dig into, and the structure of the surrounding ice suggests that they have never thawed. Their sediments are firmly compacted and totally filled with ice. No water infiltrates these chambers, much less plant roots or modern rodents. There are a few pores, but they are many times narrower than the width of any of Yashina’s seeds.

This closed world provided shelter, a continuous chill, and an effectively dry environment, that allowed the fruits to persist. At subzero temperatures, their chemical reactions slowed to a crawl. Extreme age was no longer a problem.  A fruit’s placenta is also chemically active, and is loaded with several chemicals that might have protected these specific tissues against the cold.

But the burrows weren’t completely benign environments. The underground rocks contain naturally radioactive elements, which would have bombarded the seeds with low but accumulating doses of radiation. The ones that Yashina regenerated would have amassed 70 Grays of radiation – that’s more than any other plant has absorbed while still producing viable seeds.

S.stenophylla’s resurrection shows how many treasures lie buried within the world’s permafrost. This soil, defined as that which stays below freezing for two years or more, covers a fifth of the planet’s land. It is home to bacteria, algae, fungi, plants and more. In the fossil burrows that Yashina has studied, scientists have found up to 600,000 to 800,000 seeds in individual chambers.

In Norway’s Svalbard Global Seed Vault, scientists have frozen thousands of seeds in an underground cavern, as a back-up in case of agricultural crises. But nature has already produced similar frozen seed banks. Siberia, Alaska and the Yukon could act as one massive freezer, where ancient life has been stored, waiting to greet the world again.

Update: The lead author, David Gilichinsky passed away on 18 February, just two days before his final paper was published.

Reference: Yashina, Gubin, Maksimovich, Yashina, Gakhova & Gilichinsky. 2011. Regeneration of whole fertile plants from 30,000-y-old fruit tissue buried in Siberian permafrost. PNAS

More on ancient plants:

2,000 year old “Phoenix” seed rises from the ashes

The 13,000-year old tree that survives by cloning itself


Comments (31)

  1. Matt Gruner

    Is there any evidence for viruses or other plant parasites surviving this sort of time travel? Could the melting permafrost in North America release more than methane?

  2. Daniel J. Andrews

    Nice!! Now there’ll be an interesting race to see who can regenerate the oldest seeds. Maybe there’ll be an extinct plant they can bring back?

    Incidentally, I recognized the family of the plant and thought it looked like one of the Silene species (pats himself on the back). :)

  3. Joe Clark

    Older by “an order of magniture”?

  4. Daniel J. Andrews

    Matt—yes, the melting permafrost will and is releasing methane. Decomposing organisms produce methane. Thaw out frozen plant material and it will begin to rot and produce methane. Dr. Archer explores what a worst case scenario would look like if the permafrost released a lot of its methane–see link below (the worst case doesn’t seem to lead to mass extinction or runaway greenhouse effect according to his calculations). If you’re interested in more about methane, see his Much Ado About Methane article.

  5. Deborah
  6. TheManOnTheStreet

    I’m skeptical. I went to google scholar to find this article (the DOI doesn’t work), and Yashina has been publishing numerous articles about reanimated ice-age Silene stenophylla’s since 2002 – and _no one else has reproduced her results_. I can’t find anyone coming even close.

  7. Luna_the_cat

    @Daniel J. Andrews — Matt’s question was, could the melting permafrost release MORE than methane, as in, could there be pathogens lurking there as well — and I find this an interesting question too. After all, the samples which provided us with definitive knowledge of the 1918 flu came from corpses exhumed from the Alaskan permafrost.

    My other question would be, given how much permafrost around the world is currently melting, are there any expeditions to try to find what is in it before it all rots?

  8. Ice Age

    It was Scrat who buried the fruit! :-)

  9. bob1

    I too can’t find this paper at all, it isn’t recorded on Pubmed, nor at the PNAS website, nor on google scholar, using a combination of the author’s names and/or variations in the title. The DOI from this page doesn’t work nor will the one the New Scientist supplies.
    I can’t even find a reference using simple google search, other than media sites. What’s going on?

  10. Business Nunya

    I have always loved science, I work in a laboratory and I marvel at 99% of what I read about. And I emphatically believe that these scientists should quit while they’re ahead. The risks don’t outweigh the quest for knowledge here. The world evolved into it’s current state today specifically without these plants and animals.

  11. SteveF

    “I can’t even find a reference using simple google search, other than media sites. What’s going on?”

    PNAS being awful is what’s going on. The paper will appear at some point this week. Keep an eye on:

  12. Re: not finding the paper. Read this:

    Re: the imagined “risks”. No, it’s not like this plant disappeared during the last Ice Age. As I said, it’s still around. This is just an ancient and subtly different version of it. FEAR THE SLIGHTLY WIDER PETALS.

  13. «PNAS being awful is what’s going on.» A pity that Yashina et all didn’t choose to publish on PLOS instead….


  14. Eleanor

    I’m waiting for them to do this with woolly mammoths.

  15. I want to point out that this is *very* different from cloning a mammoth. You’re basically thawing out the plant and putting it in the right liquid. To clone a mammoth, you’ll need more sophisticated genetic techniques and an elephant to act as a surrogate parent. Here’s a good feature on why cloning a mammoth is incredibly hard, even if you have the right frozen material

  16. Trump

    Gives new meaning to the phrase “I’m just a squirrel trying to get a nut”

  17. Robbie

    So there’s hope for Ted Williams’ head after all!

  18. Sadly, David Gilichinsky has passed away three days ago at the age of 63.

  19. Fat_Daddy_Cool

    At Eleanor

    To hard to plant a pachyderm from the permafrost.

  20. Daniel J. Andrews

    oops, reading fail on my part. Thanks Luna. heh, I pat myself on the back for identifying a resurrected plant and then make a grade school reading comprehension error in Matt’s post. The proverb, Pride goeth before a fall, seems particularly apt in this case. sigh.

    And sorry, Matt, for misreading your question.

  21. Eleanor

    I’m prepared to wait for my mammoth :)

  22. sharon

    so, is this actually a good thing or a bad thing? and it can’t survive current conditions can it?

  23. blar

    @sharon: It’s neither good nor bad. It’s just a thing.

    The plant probably can survive, if it’s planted in the right place.

  24. chris

    If you read the article, Sharon, you’ll se it already has survived. Was that just too long for you to get through?

  25. Noumenon

    Was the amount of radiation absorbed actually measured or simply calculated from the age and the characteristics of the surrounding soil? My creationist friend thinks the fact that the plants grew means the seeds can’t have absorbed as much radiation as they thought.

  26. Jumblepudding

    I remember having a gradeschool teacher read my class a picture book about the seeds buried by the lemmings, which tied a message of hope to the fact that the ancient seeds found by the canadian team were still viable as plants.(each Seed is a Promise or something) I was disappointed when I found out that this was proven false. I find it amazing that the message of that childrens’ book has been redeemed.

  27. Susan Durham

    Next there’ll be extinct plants lining up at the lab to be reproduced!

  28. PhD-JD

    Not to be alarmist, but this reads like the beginning of a SCI-FI novel. The plants and the existing ecosystem interact and then all human life is gone. I Didn’t say it would be a GOOD novel. Probably by the time the article is published, production companies like the Asylum (which is very good) will have a script in progress and we’ll get to see the movie on SyFy by next summer!

  29. Vladimer P Slauden

    One word, ‘TRIFFIDS’. What if a plant species like carnivious Triffids were brought back to populate the earth and attacked animal & human life? Beware! Be very afraid!

  30. LJames

    I’m amazed. This is wonderful. I really appreciate the hard work these scientists do to unlock the mysteries of evolution; to reveal what our environment was like in less than a blink of an eye in the geological time scale. I appreciate all that scientists do and how hard they work to unlock the mysteries of our precious planet and all of the most fascinating flora and fauna that were surviving precursors to modern species, today. Thank you to the Russian team to share with us the wonders of what lies beneath the permafrost. We humans can’t fathom deep time, but we have come to an understanding that the last Ice Age really wasn’t that long ago in the grand scheme of things.


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