. | . |
Increasing forest cover in the Eifel region 11,000 years ago resulted in the local loss of megafauna by Staff Writers Mainz, Germany (SPX) Dec 22, 2022
Herds of megafauna, such as mammoth and bison, have roamed the prehistoric plains in what is today's Central Europe for several tens of thousands of years. As woodland expanded at the end of the last Ice Age, the numbers of these animals declined and by roughly 11,000 years ago, they had completely vanished from this region. Thus, the growth of forests was the main factor that determined the extinction of such megafauna in Central Europe. This is the conclusion reached in a study conducted by Professor Frank Sirocko of Johannes Gutenberg University Mainz (JGU), together with researchers from the Max Planck Institute for Chemistry, the University of Wollongong in Australia, and the University of Gottingen. The project involved the analysis of sediment layers taken from two Eifel maars, i.e., former volcanic craters that had subsequently become lakes. The researchers used these to reconstruct landscape changes and megafauna abundance in the area over the last 60,000 years. The results showed that human hunters and large mammals had actually co-existed here over several thousand years. "The sediments from the Eifel maars have provided us with no evidence that it was humans who were responsible for the eradication of these animals," stated Sirocko. The so-called overkill hypothesis discussed in North America could thus not be confirmed for Central Europe.
Previous vegetation and animal populations can be identified from pollen and fungal spores in sediments On the basis of the grains of pollen, the researchers established that some 60,000 to 48,000 years ago the Eifel region was covered by spruce woods that succumbed to several cold phases, which transformed the landscape into more open forest steppe. This kind of terrain remained predominant from 43,000 to 30,000 years before the present. Subsequently, the forest tundra of the Eifel became an Ice Age polar desert where only grass grew. The megafauna fecal fungal spores show that it was these environments which were continuously inhabited by large mammals from 48,000 to some 11,000 years ago. Datable bones found in caves in Belgium and gravel deposits in the Rhine valley document that mammoth, woolly rhinoceros, bison, horses, reindeer, and giant deer found the cold phases more accommodating. The sparse forests of the warmer phases were the preferred habitat of red deer, elk, and the European bison.
Development of woodlands deprived megafauna of their food source At the same time, the arrival of modern humans in Central Europe 43,000 years ago also had little effect on the presence of local megafauna. Instead, times at which extensive numbers of large mammals were living here coincided with periods in which there was a denser population of humans. "This is most apparent some 15,000 years ago. At that time, we find the largest herds of megafauna along with the archaeologically confirmed presence of human hunters in the Rhine valley," Sirocko pointed out. The Magdalenian culture site at Gonnersdorf in northern Rhineland-Palatinate has been extensively excavated by the Romisch-Germanisches Zentralmuseum Mainz - Leibniz Research Institute for Archaeology (RGZM) in Mainz. The researchers claim that even in this period, towards the end of the last Ice Age, grassed landscapes were still spreading. This was the era in which the solar irradiation of the Northern Hemisphere began to increase and global sea levels started to rise, eventually flooding the formerly land regions in the English Channel and the North Sea and thus presumably progressively forcing the herds of megafauna away to seek refuge in Central Europe. "The many late glacial maar lakes and silted-up swamps in dried-out maars in the Eifel region must have proved particularly attractive to megafauna," concluded Sirocko. "And it was the resultant large herds that must have enticed the late Ice Age hunters."
Sediments of the Eifel maars do not substantiate the overkill hypothesis The large mammals migrated away only when birch forests began to predominate in the terrain 13,300 years ago. From 11,000 years ago there is no longer evidence of the presence of large herds of megafauna as thick woods had taken over the Eifel, a setting in which large mammals could not survive.
Research Report:Thresholds for the presence of glacial megafauna in central Europe during the last 60,000 years
Metabolic hack makes ocean algae more resilient to 21st century climate change Daejeon, South Korea (SPX) Dec 22, 2022 A study published in Science Advances by an international team of scientists provides clear evidence that marine phytoplankton are much more resilient to future climate change than previously thought. Combining data from the long-term Hawai'i Ocean Time-series program with new climate model simulations conducted on one of South Korea's fastest supercomputers, the scientists revealed that a mechanism, known as nutrient uptake plasticity, allows marine algae to adapt and cope with nutrient-poor ocea ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |