Antarctica - the frozen, windswept continent with ice over 3km thick. Yet the ice caps have only appeared relatively recently in geological history. It is hard to think that once, Antarctica was a lush green land with rainforests in the south.
Since then, more plant fossils have been found preserved within sandstone and mudstone of the Antarctic Peninsula, some dating back as far as 100-250 million years ago. This was when the world was experiencing extreme Greenhouse effects, with temperatures much warmer than today.
Clusters of petrified tree stumps were found upright in their original living positions. This has allowed us estimate that the trees grew up to about 25 metres tall based on the diameter of the trunk. Furthermore, they grew very densely, roughly 1000 trees per acre.
The plants and trees would have needed very special adaptations to survive in Antarctica. This is due to the fact that in the summer the days have 24 hours of sunlight, but in the winter there is only darkness. Tree rings show that they only grew in the summer, much like trees today, however trees back then would have stopped growth due to light levels whereas today it is due to temperature.
The question that has been asked many a time now is 'With the world experiencing another event of global warming, will we see trees back on Antarctica?' Although it is entirely possible,
plant species would have to migrate the Southern Ocean from Australia or South America for this to happen.
Evidence for this was first discovered over 100 years ago by explorer Robert Falcon Scott in 1912. He stumbled over fossils on the Beardmore Glacier full of leaves and twigs. Some fossils that were found proved to be remains of Beech, Pine and Fern trees, dated at 3-5 million years old, very similar to those found in New Zealand and Tasmania today.
Fossil leaf of Glossopteris Indica collected by Captain Scott
Since then, more plant fossils have been found preserved within sandstone and mudstone of the Antarctic Peninsula, some dating back as far as 100-250 million years ago. This was when the world was experiencing extreme Greenhouse effects, with temperatures much warmer than today.
Clusters of petrified tree stumps were found upright in their original living positions. This has allowed us estimate that the trees grew up to about 25 metres tall based on the diameter of the trunk. Furthermore, they grew very densely, roughly 1000 trees per acre.
The plants and trees would have needed very special adaptations to survive in Antarctica. This is due to the fact that in the summer the days have 24 hours of sunlight, but in the winter there is only darkness. Tree rings show that they only grew in the summer, much like trees today, however trees back then would have stopped growth due to light levels whereas today it is due to temperature.
The question that has been asked many a time now is 'With the world experiencing another event of global warming, will we see trees back on Antarctica?' Although it is entirely possible,
plant species would have to migrate the Southern Ocean from Australia or South America for this to happen.
Antarctica today
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