Similar to the land dwelling Cynognathus, the Lystrosaurus would have not had the swimming capability to traverse any ocean. Modern day representation of the Glossopteris. Possibly the most important fossil evidence found is the plant, Glossopteris. Known as a woody, seed bearing tree, the Glossopteris is named after the Greek description for tongue due to its tongue shaped leaves and is the largest genus of the extinct descendant of seed ferns.
Reaching as tall as 30 meters, the Glossopteris emerged during the early Permian period million years ago and became the dominant land plant species until the end of the Permian. Now, the Glossopteris seed is known to be large and bulky and therefore could not have drifted or flown across the oceans to a separate continent.
Description showing the fossil locations of the Mesosaurus, Cynognathus, Lystrosaurus, and Glossopteris spread across different continents. If the continents of the Southern Hemisphere are put together, the distribution of these four fossil types form continuous patterns across continental boundaries.
Of course, possible explanations are brought to attention. One explanation is the species could have migrated via a land bridge or swam to the other continents. However, a land bridge is not applicable due to the differences in densities between the continents and oceans floor and violation of the isostasy concept. Alternating patterns of magnetic anomalies on the ocean floor indicated seafloor spreading , where new plate material is born.
Magnetic minerals aligned in ancient rocks on continents also showed that the continents have shifted relative to one another. A map of the continents inspired Wegener's quest to explain Earth's geologic history. Trained as a meteorologist, he was intrigued by the interlocking fit of Africa's and South America's shorelines. Wegener then assembled an impressive amount of evidence to show that Earth's continents were once connected in a single supercontinent. Wegener knew that fossil plants and animals such as mesosaurs , a freshwater reptile found only South America and Africa during the Permian period, could be found on many continents.
He also matched up rocks on either side of the Atlantic Ocean like puzzle pieces. In fact, plates moving together created the highest mountains in the world, the Himalayans, and the mountains are still growing due to the plates pushing together, even now, , according to National Geographic.
Despite his incredible evidence for continental drift, Wegener never lived to see his theory gain wider acceptance. He died in at age 50 just two days after his birthday while on a scientific expedition in Greenland, according to the University of Berkley. Tests were done, but with the most reliable instruments of the time no movement of the continents was detected.
The edition of the Encyclopedia Britannica still did not believe Wegener, but that year many geologists began siding with him, in view of new evidence. This new theory— plate tectonics —also explained that earthquakes and tsunamis occur when two plates rub against one another, and that when they collide head-on, large mountain ranges are formed. In addition, thanks to geolocation satellites, we are now able to detect that Europe and North America are moving apart, although at the same speed that a fingernail grows: two metres in a lifetime.
Today we have all learned at school—or even before, in cartoons—the theory of continental drift. But Wegener died in , long before his success was recognised.
During an expedition in Greenland, he left the camp for supplies and was found frozen months later. He was buried there and is still there, although he is now about two metres further away from his birthplace in Berlin. Click Enter. Login Profile.
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