Science News. Bijl, David R. Greenwood, Steven M. Bohaty, Stefan Schouten, James A. Ian Raine, Claire E. Huck, Tina van de Flierdt, Stewart S. Jamieson, Catherine E. Bendle, Peter K. Bijl, Steven M. Bohaty, Stephanie A. Carr, Robert B. Dunbar, Jhon J. Hayden, Masao Iwai, Francisco J.
Olney, Sandra Passchier, Stephen F. Professor Francis has been polishing thin slices of these logs to reveal the "annual rings" in the wood. Studying these tree-rings sheds light on ancient climate. Possibly the weirdest and most baffling feature of the polar forests was their adaptation to the Antarctic "light regime".
Near the pole, night reigns all winter long while in the summer, the sun shines even at midnight. Professor David Beerling of the University of Sheffield, and author of Emerald Planet, explained the challenge that Antarctic trees must have faced in this unusual environment: "During prolonged periods of warm winter darkness, trees consume their food store," he said.
And if this goes on for too long, they will eventually "starve". To understand how trees survived against the odds, Professor Beerling has been investigating the kinds of plants that once grew on Antarctica. These include trees like the Ginkgo , a living fossil.
His experiments showed that trees could cope remarkably well with the strange environment. Although they used up food stores in the winter, they more than made up for this by their ability to photosynthesise 24 hours per day in the summer. In fact the main problem seems to have been that trees did not know when to stop.
However, it wasn't just trees that had to find ways to cope with the unusual polar conditions. Amazing fossil discoveries show that dinosaurs foraged in the tangled undergrowth. Professor Thomas Rich of the Victoria Museum, Australia, is a world-famous dinosaur-hunter, responsible for finding several polar dinosaurs. Over the past 20 years, he has meticulously excavated fossil sites in southern Australia. This region was positioned just off the east coast of Antarctica, million years ago.
His finds raise an interesting question: did Antarctic dinosaurs migrate during the winter, or were they adapted to living in the dark forests of the polar night? Professor Rich thinks he knows the answer: "The only complete dinosaur skeleton that we've found is Leaellynasaura.
The study was carried out by an international team of experts who analyzed preserved roots, pollen, and spores found in cores of sediment drilled within kilometers of the South Pole. The fossilized soil is estimated to be 90 million years old, placing it in the mid-Cretaceous, a geological period during which the dinosaurs were at their heyday.
This was also the warmest period in the past million years, with temperatures easily reaching 35 degrees Celsius in the tropics. Sea levels were also a staggering meters feet higher than today.
However, not much is known about what the environment looked like in the South Pole during that period. Researchers knew they were on to something when they noticed a strange color in a section of a sediment core drilled into the seabed near the Pine Island and Thwaites glaciers in West Antarctica.
Join the ZME newsletter for amazing science news, features, and exclusive scoops. More than 40, subscribers can't be wrong. Upon analyzing this section with computer tomography techniques, the scientists came across a dense network of fossil roots. The samples were pristinely preserved, allowing the researchers to make out individual cell structures.
There were even remnants of flowering plants — the earliest ever found at such high Antarctic latitudes.
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