Antarctic Fossils Reveal the Continent’s Lush Past

By Nathaniel Scharping | November 17, 2017 3:20 pm
(Credit: Gustav Gullstrand/Unsplash)

(Credit: Gustav Gullstrand/Unsplash)

Antarctica, a land of near-lunar desolation and conditions so bleak few plants or animals dare stay, was once covered with a blanket of lush greenery.

The conception of the ice-coated continent as a forested Eden emerged in the early 1900s when Robert Falcon Scott, a British explorer, found plant fossils during an expedition to the South Pole. Now, researchers working in the Trans-Antarctic mountains, where they may be the first to tread for hundreds of millions of years, are digging deeper into the Antarctic’s deep past. Their work is revealing that not only was Antarctica home to greenery, it was veritably cloaked in it.

Old, Cold Rocks

University of Wisconsin-Milwaukee geologists Erik Gulbranson and John Isbell were part of a team that traveled to the remote mountain range during the Antarctic summer last year to search for evidence about the continent’s more lively past. The mountains are one of the few places in Antarctica where rock is exposed, giving geologists and paleobotanists a rare chance to dig for fossils. Even more exciting for them — some of the rock formations date back to right around the end-Permian extinction, a still poorly-understood event that killed off over 90 percent of the world’s marine life and is the largest extinction event we know of.

During their work last year, Gulbranson and Isbell found the remains of 13 fossilized trees dating to around 260 million years ago, about 8 million years before the end-Permian extinction. Prevalent among them is one species of tree, Glossopteris, that’s thought to have dominated the landscape during that time. It’s a species of tree that had both seeds and long tongue-shaped leaves that likely fell off at the end of the summer.

In the Permian Antarctic, Glossopteris was king. Forests of the trees likely stretched across the entire continent, and well into South America, Africa, India and Australia as well. These disparate landmasses were once all part of an ancient supercontinent known as Gondwana. Glossopteris, in fact, was the first real evidence that Gondwana existed. The same tree could only have shown up in so many different places around the same time if they were connected by land.

Polar Trees

Living in Antarctica, though, the species was subject to conditions no tree today faces. Six months of light alternated with six months of darkness. That means the trees’ needed to find a way to survive without nourishing sunlight for half the year. But some of the preserved trees show some astonishing detail, offering clues as to how they pulled through.

These clues come in the form of tree rings and even individual cells preserved in the fossils. Trees today go through cycles of growth and rest, tuned to the seasons, and the difference shows up in the cells — bigger when growing, smaller when resting. There’s no such distinction among the Glossopteris says Patty Ryberg, a paleobotanist at Park University and member of the team.

“In Antarctic trees they’re all big cells,” she says. “They’re just running and running and running without stopping for six months so we’re trying to figure out how they grow down there.”

Around 252 million year ago, the once-mighty species disappeared as the end-Permian extinction closed its gaunt hand over countless species of that era. The culprit was likely one we’re familiar with today: climate change. Scientists think that volcanic activity in what is now Russia, in an area known as the Siberian traps, pushed enough CO2 into the atmosphere to warm the planet and change the oceans beyond what most life could adapt to.

The environmental consequences were severe enough that scientists think it took some 10 million years for life on Earth to recover, and the Glossopteris trees were likely wiped out. Studying fossils from both right before and right after the event, along with rocks that may give clues about the environment at the time, gives researchers an idea of how the extinction happened and just how widespread it was.

Ryberg and Isbell are currently in New Zealand, waiting for inclement weather to lift so  they can continue on to Antarctica. Gulbranson will follow in a few weeks, and they plan to return to the Tran-Antarctic mountains once again. In the cold and loneliness, they’ll be walking among the ghosts of a forest long dead, searching for evidence of greener days.

CATEGORIZED UNDER: Environment, Living World
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  • OWilson

    Fossil trees found in the Antarctic does not necessarily indicate that they grew in the area now defined as the South Pole.

    The continental shelf on which they once grew, might have been carried there by tectonic forces, or may have grown there when the Earths orbital tilt was different.

    • ES Prado

      What my initial thought was. Dont think there is a way to calculate where Antartica was during these periods. I
      Also have to account for earth axis as u mentioned- i think scientific data suggests Earth was in a very warm cycle 250 million years ago. So these tress probably werent in a severely cold climate

      • Antoine Beauchamp

        I’m no scientist, but I agree. Don’t see any need to believe trees went through 6 month dark and light cycles.

    • Thomas Buzzi

      It seems that the trees got their start while Antarctica was much further north and slowly died out as the landmass they lived on via tectonic activity drifted south to an impossible climate range. Fascinating stuff!

  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    Antarctica has coal deposits across the Transantarctic Mountains. Examine the macerals therein.

    • Electronic Yogi

      “At The Mountains of Madness” by H.P. Lovecraft

  • http://whatdafuckwad.webs.com donaldwestington

    I knew they would throw some BS political AGW propaganda in there somewhere. We’re not falling for your AGW lies, Discover. Well, the smart ones out there aren’t buying your anthropomorphic global warming lies, anyways.

    I don’t read replies.

    • Hal Johnson

      Best you don’t read replies as it would be to difficult for someone of your limited intellect to comprehend the logic of the scientific mind. For those of such a finite level of understanding perhaps it’s best to bury your heads in sand and await the fate of the planet. It will mean it will be more difficult to see the end coming. Of course, those with brighter minds will be fighting to the end or will have left this poisoned cinder.

    • Shoes4Industry

      Hottest Thanksgiving in Los Angeles ever…

    • George Levanduski

      Where is the BS AGW propaganda in the article? You apparently added an assumed “A” for anthropomorphic. Global climate change is on record, whether or not humans contribute significantly to the cause.

      • Steve Sykes

        Agree. Global warming is here, but I doubt human activity has much bearing on the cause. It is a part of the natural cycle of our planet.

        • Atona Sr

          Global warming is not natural and it refers to the psychos calling themselves “humans” warming (artificially, and that’s why there are so many drillings into the ground, under the disguise of oil and gas extraction) the underground waters, which then press magma and can cause volcanic activity and earthquales. Actually. abnormal fires that hit Mediterranean this summer were caused by such ‘climate change’.
          The solution is only one – get rid of the 1% gone-crazy psycopaths and their puppet politicians, starting with the presidents of America AND Russia (they’re in).

          • Peter Lance

            I tend to agree with you Atona Sr. Is there a plan suggesting a way how to ‘get-rid-of’ the 1% gone-crazy psychopaths and their puppet politicians? I hope this doesn’t come across as flippant, if there is no plan, we need a plan.

          • Steve Sykes
          • Steve Sykes

            In the last 450,000 years there have been 6 warming cycles. In the first 5 – each was followed by an Ice Age. We are currently in the 6th warming cycle.

      • okiejoe

        Humans certainly didn’t have any hand in changing the climate 260 million years ago. Of course, now we can make the same change in a few generations that took millions of years then.

  • bwana

    No reason to believe the Antarctic was always at the south pole. I could very well have been considerably farther north and had sunlight year round.

  • nik

    ”Scientists think that volcanic activity in what is now Russia, in an area known as the Siberian traps, pushed enough CO2 into the atmosphere to warm the planet and change the oceans beyond what most life could adapt to.”
    Another bunch of ignorant’s who have swallowed the ”global warming” carbon tax propaganda, fraud.
    It has been determined that the Siberian Traps were formed by massive continuous volcanic activity, that lasted ten of thousands of years.
    It didnt ”warm the planet” it pushed into an Ice Age, that lasted several million years. Even within recent human records, a volcanic eruption caused ”the year without a summer.”
    Volcanoes do not cause planet warming, they block sunlight that causes cooling!
    Its more likely that these trees were killed by lack of sunlight, and then, initially preserved by cold, which prevented them from rotting. In a hot climate they would have rotted very rapidly, as trees do in the equatorial forests even now, in what is a relatively cool global climate.

    • Steve Sykes

      The last information I read on this subject stated there was a brief period of global warming ~ followed by an Ice Age.

      • nik

        It was the entry into the major ice age that triggered the volcanic disturbances.

        • Steve Sykes

          In the last 450,000 years there have been 6 warming cycles. In the first 5 – each was followed by an Ice Age. We are currently in the 6th warming cycle.

          • nik

            The solar system is presently in the middle of a major ice age. These occur every 150 million years, and are caused by the solar system entering one of the arms of the galaxy, as it orbits the centre of the galaxy. These last about 50 million years from start to finish.
            Superimposed on that are the Earths Malenkovitch cycles, caused by the variability of the Earths orbit.which produce minor ice ages. These have a period of about 100,000 years, as shown by deep sea and lake core drillings tracing climate back about 1 million years, and within those there is an inter ice age of 10-15 thousand years, which we are experiencing now.
            This one has already lasted most of its period, and so the Earth will be returning to a full ice age in the not too distant future. The core drillings shoe that the return to an ice age, from inter ice age can occur in as little as 20-50 years.
            One of the paradoxes of a returning ice age, is that it first gets warmer. This is accompanied by widespread forest fires, and increased volcanic and earthquake activity.
            Noticed any of those lately?

          • nik

            There are two systems that affect Earths climate.

            The major one is due to the solar systems orbit around the centre of the galaxy. This orbit is about 600 million years. During that period, the solar system passes through the arms of the galaxy, at 150 million year intervals. Each passage can take from 25 to 50 million years, and causes the Earth to experience a major ice age.during that passage. It will also experience an increase in volcanic activity, due to gravitational effects, and an increase in meteor incidents.

            600 million years ago, the Earth exited a state referred to as ”Snowball Earth, when the Earth was totally covered in snow, for millions of years, nearly all life died. Following that there was another ice age/extinction event at 450 million years ago, 300 million years ago, (the Permian Extinction) when the Siberian Steppes were formed, 150 million years ago, and NOW. This period will be a repeat of the ‘Snowball Earth’ event!

            Total human existence, is maybe 300-400 thousand years, and has been entirely during this last major ice age.

            The second system that affects Earths climate, is due to the eccentricities of its orbit around the Sun, and these are called Malenkovitch cycles. Each complete cycle last about 100,000 years, roughly 85-90 thousand years of Ice age, and 10-15 thousand years of inter ice age. These are superimposed on the major galactic ice ages.
            (This inter ice age has been the coldest since the Permian Extinction 270 million years ago.)

            From deep sea core drillings, it has been ascertained that over the last million years there have been 10 ‘Malenkovitch’ ice ages, and the transition from inter ice age (the warming period) to full ice age can occur in as little as 20-50 years. Towards the end of the warm period, it paradoxically first gets warmer. There is an increase in volcanic and earthquake activity, due to plate tectonic movements caused by the loss of ice. There is also an increase in forests fires, caused by the nutrients in the ground being gradually washed down into the soil until they are out of reach of the tree roots, weakening the trees, and making them more vulnerable.
            Volcanic action can bury trees in ash, so preserving them, and they eventually become fossilised.

            During the periods between major ice ages, average global temperature is more than double present, and the Earth has no ice caps, so it would be quite feasible for trees to grow in the Antarctic at that time. However, once the major ice age commenced, it would eventually become too cold for trees to continue to grow, and they would die out.

          • John Maslanka

            There seems to be one thing missing from the discussion above. That is the matter of continental drift. Over the course of eons of time, continents have formed, joined and separated and drifted around the globe. FWIW I personally find it hard to believe that over the ages that the continents of North and South America have exchanged places, but that is what the geologists indicate. If this is the case, then it is also plausible that the continent of Antarctica was once in the tropics prior to migrating into its current position on the globe. This is an alternative explanation for why the fossils of trees on that continent do not have growth rings.

          • nik

            There are some animations on the web, that show the continental positions over time, with the continent bouncing off each other, and ricocheting around. The movements are far from simple, but yes, Antarctica was further north at one time, and would have been warmer.
            You’ll have to search to find out exactly when.

          • nik

            I did post an answer, but it mysteriously disappeared.
            If you google; historical plate tectonics animations, there are loads to choose from. And you will see on some that Antarctica was warm and green several million years ago, even in its present position. Normal climate on Earth is much hotter than present.

        • Jug

          Bassackwards!

          • nik

            Whatever turns you on dearie!

  • Thomas Buzzi

    Donald Westington, I had to laugh at your closed minded thought pattern and laughed even harder with your remark that you do not read replies. What a perfect way to protect your fragile, closed mindedness.

  • Rick Smithson

    I’d be interested in growing saplings with six months of light/dark.
    I suspect some Alaskan and Russian trees could survive it.

  • Chris Hatcher

    Who financed that trip? I’m sure the permits cost a fortune. Antarctica has been off-limits to private entities since the treaty signed in the 50s. Big secrets there.
    You all sound Intoxicated by your own vanity and intellect.

    • Atona Sr

      I wish you were right, but you aren;t. Now every a***le can come to “Antarctica” and work on the psychopaths’goal of artificially causing the global catastrophe by “warming”. ANTARCTICA MUST BE PROTECTED TO ONLY ‘PENGUINS’ LIVING THERE!

  • Electronic Yogi

    “At The Mountains of Madness” by H.P. Lovecraft.

  • Christine Fiscus

    Satellite technology has located an impact crater in Antarctica that is three times the size of the one that killed the dinosaurs. It has been dated to the Permian extinction, and may have caused it. Shock waves from the impact would have travelled through the Earth and converged directly opposite the impact site, in Siberia.

  • George Levanduski

    The last polar shift about 13,000 years ago involved the effects of a comet strike (in the sea outside of the Carolinas) that cracked open the deep sea trenches, allowing lava to escape from the reservoir under the supposed ill-fated Atlantis. The resulting balance shift caused the North Pole to move from the Hudson Bay to its present vicinity. The megafauna in what had been a favorable temperate climate location suddenly found themselves in arctic conditions and subject to extinction. Ice-bound wooly mammoths have been accessed and found with tell-tale grasses in their mouths and stomachs. Explorers reported cooking and eating palatable meat from one of these animals.

    Thus the shift can be alarmingly rapid. It seems likely that the surprising condition of the Permian trees is a result of a similar rapid shift. The speculated adaptation period may not have been available. My apology for perhaps raining on the parade of all who anticipate having a cellular mystery to unravel.

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