After studying these fossil leaves, we know more about the diversity and ecology of ancient forests that grew across Antarctica, and both climatic and local influences on these forests when Earth experienced warmer climates before the planet cooled and the ice caps grew.
Many plant groups that are considered unique to Australia occurred in South America at this time, such as Eucalyptus , the iconic gum trees.
Gondwanan floral remnants, such as Southern Beech Nothofagus flowering trees, large kauri- and bunya-type conifers Araucariaceae and plum pines Podocarpaceae , are just some of the groups that occur in the cool and warm temperate forests that we see growing today in Tasmania, Victoria, South East Australia, in New Zealand and in Patagonia in southern South America.
We have previously published data that determined what the climate was like in the deep past by analysing the leaf architecture. Leaf margins together with other key leaf characters indicate mean annual temperatures of Exchange, and migration of many species must have occurred across Antarctica during the Paleocene, which acted as a gateway for interchange between South American and Australasian floras, increasing our understanding of the origin and evolution of modern Southern Hemisphere floras.
Our further research will focus on the diversity, modern relationships and floral evolution of the tooth-margin leaves that helped us to determine the mean annual temperatures of these high latitude forests at this crucial time of rapid warming. Antarctica today is a cold, inhospitable desert; however, in the more distant past, the climate was much warmer. Abundant finds of fossil leaves and wood point to the existence of extensive forestation in earlier geological periods, even to within a few degrees of latitude of the South Pole itself.
Dinosaurs, and later, marsupial mammals once roamed across its surface. It contains more than high-resolution images of fossil specimens. Scientific data and any references relating to the specimens are displayed alongside the images. Specimens can be found by browsing through animal and plant groups; or by searching using the descriptive information recorded for each fossil where known , including location, stratigraphy, geological age and specimen number.
Most of the fossils are from the Mesozoic era —65 million years ago , which reflects the age of rocks preserved in the Antarctic Peninsula where they are from. This was the age of the dinosaurs, and an era which has greatly improved our understanding of the evolutionary changes, continental movements and climates leading up to today.
The Argentina Antarctic Institute got involved and started excavating the fossil as part of its annual summer research expeditions, but the giant reptile was uncovered at a glacial pace due to weather and logistics. On active days, the team had to wait for the sun to defrost the soil before they could excavate, and every piece wrested from the dirt would then need to be shipped by helicopter to the Argentine Marambio Base a few miles away. The weather controls all. They estimate that the as-yet-unnamed elasmosaur weighed between While some previously known Aristonectes have weighed about 11 tons or so, most other elasmosaurs only come in at around five tons.
Schulp has worked on some plesiosaurs from the Netherlands , but he says the aquatic reptiles are very different in the Southern Hemisphere. The new specimen is also very interesting because it dates so close to the end of the Cretaceous—just 30, years before the mass extinction event that wiped out the non-avian dinosaurs about 66 million years ago. A lot of marine life would have needed to thrive there to satisfy the appetite of such a large creature, so the fact that these animals continued to exist so late in the Cretaceous adds to the evidence that the aquatic world, at least, was doing just fine right up until the sudden mass extinction.
Would the dinosaurs have died out if not for that asteroid? The different morphology of this species also shows that specialization was still happening at this late point in the existence of plesiosaurs. This nearly whole, deep-black skull belongs to the most complete specimen of Tyrannosaurus rex on display in Europe, an individual nicknamed Tristan Otto.
Schulp adds that the work moves our knowledge of plesiosaurs forward, and he is excited to see Argentine paleontologists go back out there and find more fossils. It was an adventure. All rights reserved. Science News. Warning from 'Antarctica's last forests' Deepest point on land found in Antarctica Journey to the 'doomsday glacier'. This video can not be played To play this video you need to enable JavaScript in your browser. The fossil root material shows up green in this 3D X-ray movie of a sediment core.
Dr Johann Klages: "There would have been no large ice masses on Antarctica". The MeBo seafloor drilling system. The MeBo drill system was lowered to the ocean floor, 1,m below the water surface.
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