Interview the Austrian paleontologist Dr. Alexander Luke Eder (photo above) - Curator of Mesozoic Geology and Paleontology Department, Natural History Museum Wien (NHM) -, who is heading a research team that explores the next three years one of the biggest crises in Earth history. Main collaborator in this project is M.Sc. Susanne Mayr from NHM.
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Question: Dr. Luke Eder, how to read in the media, you expect your team to new and interesting insights into the great mass extinction in the seas of the Triassic period, about 220 million years ago? We know already, so this global collapse of marine ecosystems has been triggered?
Answer: For a long time in science sea level fluctuations as the main reasons for the extinction of reef organisms during the Carnian Crisis. Today we go out of several possible causes. Warmer and more humid (ie humid) air is considered certain. This in turn means, by the strong rains, increased nutrient input into the marginal seas (coastal, shallow water) and by the enormous amount of fresh water a change in salinity in the affected areas. What we today know as is precisely the salinity (salt content) can one important factor in the spread of marine organisms and not all organisms to adapt to a change in salinity. The change in salinity and increased terrigenous influence (sediment input from land) can be the time of the Carnian crisis before around 225 million years ago show well in the sedimentary rocks (clayey sediments, sandstone, etc.) which were deposited around the entire Tethys.
primary cause, but still being discussed for this warming could have been the disintegration of Pangaea, together with the orogens of Indonesia and the closure of the Paläotethys.
These activities have led to increased volcanic activity, which in turn led to increased emissions of CO2, and so after today's knowledge significantly increased the temperature.
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question: The mass killing in the oceans occurred in Karn, a stage of the Triassic period, and is named so Carnian crisis. Which groups of animals which were particularly affected?
Answer: Especially it hit the shallow water organisms such as corals, echinoderms (sea urchins, etc.), bryozoans, algae and sponges, but also the ammonites, which indeed inhabited slightly deeper marine areas.
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question: Was this Carnian crisis on the mainland felt, was already out early dinosaurs lived?
Answer: Yes, the tetrapods were decimated and the land plant assemblages changed. In the case of tetrapods is called a drop 4 out of 6 families who were concerned.
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Question: You and your research team with experts from eight countries to explore the Carnian crisis in the Taurus mountains in Anatolia (Turkey). What traces left by the mass extinction 225 million years ago there?
Answer: After the dramatic death of the platforms and reefs, there was a mass extinction of ammonites of the genus Orthoceltites. The nearly black limestone, in which there are up to 200 million ammonites, were deposited directly on the platform sediments. After this "event" the pool very deep and flysch-like sediments of the deep water was were deposited. How long did it take to deposit such masses of ammonites and how it came to such mass gatherings is investigated. The duration of the Carnian crisis is indeed estimated at about 2-3 million years ago. Imagine the equivalent to today's times before.
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Question: In the course of the earth there were several global mass extinctions in the oceans and on land. Can repeat something like this in the present or future?
Answer: Such a thing can, of course, always repeat. For example, by a meteorite impact as was "often" in Earth's history. The sky, however, have such good and scanned, that probably would not happen in the near future. Long-term changes such as large-scale volcanism, etc., which could lead to such crises are not currently in sight. However, as the methane ice on the shelves the oceans in the future, act in such other global warming is still uncertain.
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Question: Right now is a lot of fears of global warming and often talked about climate change. If you forget this, that the climate has changed in the course of the earth again and again and will change the future?
Answer: Global warming is here and will continue to stride, even if you see snow now, when you look out the window. All reports, whether from the Arctic, Antarctic, and even from each glacier Institute clearly indicate a warming. And can indeed be faster than us dear. What has changed is the climate in the course of the earth again and again and it will continue to change, but little consolation if we pass as it were, by nature.
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question: around 10,700 years ago was the last ice age ended. It ought to follow is actually a warm period and then again at some point a cold period? Or is this natural climate change is no longer effective?
Answer: It is actually how it went in the Earth forever. Simply put, cold to warm follows. Man can only accelerate to a certain extent the direction of something that the earth is in the truest sense of the word regardless. The person will stop what must come up with.
* Question: You are one of the few scientists who have managed to become the Austrian FWF, the Fund for Scientific Research, determined as the project manager for two large projects. What is your other big research project?
Answer: On my second FWF-project deals with the climate and environment for the Cretaceous in the Dolomites in South Tyrol. A period of about 140-110 million years is studied in all its details. Since there is now 2 years researching the latest methods to the 20 scientists from 10 nations at various internal problems. Isotopic analysis, geochemistry and paleomagnetism are just some examples of the methodology. Of course, also many macro-, micro-and Nanno-fossil groups studied. Especially, we work closely with the Natural History Museum in Bolzano, South Tyrol.
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question: Can the paleontology, the study of life in ancient times, valuable answers to questions about climate change of the future?
Answer: Comparisons are always possible. One must also not forget in all the euphoria that had some parameters in the Earth's simply different. For example, the oxygen content of air (at times to 10 times increased) or the CO2 content of the air (by volcanism). The CO2 is also in our time a mega-problem for the civilization that is correct. This problem is homemade.
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The questions for the interview, the Wiesbaden-based science writer Ernst Probst, published numerous popular science books and is the weblog http://internet-zeitung.blogspot.com operates
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Contact: Dr.
Mag Alexander LUKE EDER
curator - Mesozoic Geology and Paleontology Department
Natural History Museum Vienna
Burgring 7
A-1010 Vienna
e-mail: alexander.lukeneder (at) nhm
wien.ac.at Tel: 521777/251
Homepage: http://www.nhm-wien.ac.at/NHM/Geolog/lukeneder.htm
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