Latest news with #InstituteofTibetanPlateauResearch
Borneo Post
20-05-2025
- Science
- Borneo Post
Oyster fossils offer new insights into history of global warming
Judges check oysters after being shucked during John Bil Oyster Shucking Competition at the 2022 Restaurants Canada Show in Toronto, Canada, on May 11, 2022.(Photo by Zou Zheng/Xinhua) BEIJING (May 21): Oysters are a popular delicacy on the dining table, but they also serve as natural recorders of environmental changes. Akin to the rings of a tree, the growth bands on oyster shells reveal not only the creature's age but also the climatic conditions at the time they were formed. High temperatures in summer can boost their growth and result in wider and light-colored bands, while low temperatures in winter may slow down their growth and lead to thinner and darker bands. Scientists believe that reading the growth bands on oyster fossils dating back millions of years can reveal the environmental information of the Earth's past and offer new understanding of the planet's future. A study led by scientists from China, Germany, Britain and Madagascar focused on four oyster fossils from Madagascar and the Qinghai-Tibet Plateau dating back to the Early Cretaceous (about 140 million years ago), an era when dinosaurs thrived and the climate was warm and greenhouse-like. They discovered notable seasonal variations in sea surface temperatures, along with periodic melting of polar ice sheets and glaciers, indicating that during that ancient warm era, sea temperatures did not consistently rise but fluctuated instead, with cooler periods allowing polar ice to reform. These findings, published in the international journal Science Advances earlier this month, have challenged the long-standing view of 'minimal seasonality and rare glacial activity during greenhouse climates,' revealing the complexity of Earth's climate evolution, said lead researcher Ding Lin, an academician from the Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS). A visitor holding an oyster poses for photos at an oyster gala held in Rushan City, east China's Shandong Province, Jan. 11, 2020. (Xinhua/Guo Xulei) As early as 2014, Ding's team revealed through analysis of ostracode shell fossils that the Gangdise Mountains are older than the Himalayas. To accurately identify the growth bands, the researchers used advanced instruments to observe the microstructure of the oyster fossils and analyze their chemical composition. Global climate computing models also assisted researchers in verifying the reliability of the data. They found that in the warm Early Cretaceous, winter ocean temperatures in the Southern Hemisphere's mid-latitudes were 10 to 15 degrees Celsius lower than in summer, similar to current seasonal variations in the same region, which suggests that seasonal temperature variations were still quite noticeable under the ancient greenhouse-like climate. Moreover, seasonal glacial meltwater possibly flowed into the oceans during that time, much like the summer melting of glaciers on Greenland's ice sheet today, implying that despite the overall warm climate, glaciers still existed and would melt in summer, releasing fresh water into the oceans. 'The Early Cretaceous greenhouse Earth seems like a symphony, and its warm melodies occasionally punctuated by brief glacial notes,' said the first author He Songlin, a postdoctoral researcher at the CAS institute. He predicts that before the polar ice sheet vanishes entirely, there would be an intermediate phase characterized by periodic fluctuations in ice sheet and glacier activity due to global warming. The study highlights that climate change is not a constant warming trend. Increases in greenhouse gases can result in more frequent extreme weather rather than uniformly rising temperatures. Seagulls perch on the floating ice at the Disko Bay close to Ilulissat, Greenland, an autonomous territory of Denmark, March 22, 2025. (Xinhua/Zhao Dingzhe) The study suggests that the brief glacier events 140 million years ago were likely caused by volcanic activity and shifts in Earth's orbit. 'It reminds us that natural factors, alongside human activities, could cause unexpected cooling events in today's warming world,' said co-first author Wang Tianyang, a postdoctoral researcher at the CAS institute. Unlike the common perception of global warming as a steady rise in temperatures, the researchers warn that the climate system can behave in complex and unpredictable ways. This research opens a new window into Earth's ancient climate and reveals the planet's hidden seasonal rhythms and icy echoes, said co-author Andreas Mulch, a professor at the Senckenberg Biodiversity and Climate Research Centre. – Xinhua China climate change conservation Oysters
South China Morning Post
14-05-2025
- Science
- South China Morning Post
Climate data from Cretaceous era suggests icy interludes in dinosaurs' greenhouse
Climate data gathered from oyster fossils is challenging the common belief that Antarctica was ice-free during the Cretaceous period 140 million years ago and offers insight into climate behaviour today, according to an international team of scientists. Advertisement During that time, a period in which dinosaurs dominated, the mid-latitudes of the southern hemisphere experienced seasonal temperature changes of up to 16 degrees Celsius – comparable to those of today. Polar ice was also present, according to the researchers led by the Institute of Tibetan Plateau Research of the Chinese Academy of Sciences. 01:17 China begins 41st Antarctic expedition China begins 41st Antarctic expedition The scientists, joined by peers from the Senckenberg Biodiversity and Climate Research Centre in Germany, the University of Bristol and the University of Hull in Britain, and the University of Antananarivo in Madagascar, published their findings in the peer-reviewed journal Science Advances on May 2. First author He Songlin, from the Institute of Tibetan Plateau Research, said that the 'Early Cretaceous greenhouse Earth was like a symphony – its warm melodies occasionally punctuated by brief glacial notes', according to the institute. The team said that applying their findings to the present day offered insight into climate change. Advertisement 'Given ongoing and anticipated global warming, reductions in Arctic and Antarctic ice are expected to continue, potentially leading to completely ice-free polar regions,' they wrote in the paper. 'Despite uncertainties in these predictions, we transition from a world with perennial glacier ice to one with only seasonal ice or shifting from a predominantly white winter planet to a blue one.'
Canada Standard
13-05-2025
- Science
- Canada Standard
Oyster fossils offer new insights into history of global warming
Judges check oysters after being shucked during John Bil Oyster Shucking Competition at the 2022 Restaurants Canada Show in Toronto, Canada, on May 11, 2022.(Photo by Zou Zheng/Xinhua)BEIJING, May 13 (Xinhua) -- Oysters are a popular delicacy on the dining table, but they also serve as natural recorders of environmental to the rings of a tree, the growth bands on oyster shells reveal not only the creature's age but also the climatic conditions at the time they were formed. High temperatures in summer can boost their growth and result in wider and light-colored bands, while low temperatures in winter may slow down their growth and lead to thinner and darker believe that reading the growth bands on oyster fossils dating back millions of years can reveal the environmental information of the Earth's past and offer new understanding of the planet's future.A study led by scientists from China, Germany, Britain and Madagascar focused on four oyster fossils from Madagascar and the Qinghai-Tibet Plateau dating back to the Early Cretaceous (about 140 million years ago), an era when dinosaurs thrived and the climate was warm and discovered notable seasonal variations in sea surface temperatures, along with periodic melting of polar ice sheets and glaciers, indicating that during that ancient warm era, sea temperatures did not consistently rise but fluctuated instead, with cooler periods allowing polar ice to reform.A visitor holding an oyster poses for photos at an oyster gala held in Rushan City, east China's Shandong Province, Jan. 11, 2020. (Xinhua/Guo Xulei)These findings, published in the international journal Science Advances earlier this month, have challenged the long-standing view of "minimal seasonality and rare glacial activity during greenhouse climates," revealing the complexity of Earth's climate evolution, said lead researcher Ding Lin, an academician from the Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS).As early as 2014, Ding's team revealed through analysis of ostracode shell fossils that the Gangdise Mountains are older than the accurately identify the growth bands, the researchers used advanced instruments to observe the microstructure of the oyster fossils and analyze their chemical composition. Global climate computing models also assisted researchers in verifying the reliability of the found that in the warm Early Cretaceous, winter ocean temperatures in the Southern Hemisphere's mid-latitudes were 10 to 15 degrees Celsius lower than in summer, similar to current seasonal variations in the same region, which suggests that seasonal temperature variations were still quite noticeable under the ancient greenhouse-like seasonal glacial meltwater possibly flowed into the oceans during that time, much like the summer melting of glaciers on Greenland's ice sheet today, implying that despite the overall warm climate, glaciers still existed and would melt in summer, releasing fresh water into the oceans."The Early Cretaceous greenhouse Earth seems like a symphony, and its warm melodies occasionally punctuated by brief glacial notes," said the first author He Songlin, a postdoctoral researcher at the CAS predicts that before the polar ice sheet vanishes entirely, there would be an intermediate phase characterized by periodic fluctuations in ice sheet and glacier activity due to global perch on the floating ice at the Disko Bay close to Ilulissat, Greenland, an autonomous territory of Denmark, March 22, 2025. (Xinhua/Zhao Dingzhe)The study highlights that climate change is not a constant warming trend. Increases in greenhouse gases can result in more frequent extreme weather rather than uniformly rising study suggests that the brief glacier events 140 million years ago were likely caused by volcanic activity and shifts in Earth's orbit."It reminds us that natural factors, alongside human activities, could cause unexpected cooling events in today's warming world," said co-first author Wang Tianyang, a postdoctoral researcher at the CAS the common perception of global warming as a steady rise in temperatures, the researchers warn that the climate system can behave in complex and unpredictable research opens a new window into Earth's ancient climate and reveals the planet's hidden seasonal rhythms and icy echoes, said co-author Andreas Mulch, a professor at the Senckenberg Biodiversity and Climate Research Centre.
Yahoo
31-03-2025
- Science
- Yahoo
Stone tool discovery in China shows people in East Asia were innovating during the Middle Paleolithic, like in Europe and Middle East
New technologies today often involve electronic devices that are smaller and smarter than before. During the Middle Paleolithic, when Neanderthals were modern humans' neighbors, new technologies meant something quite different: new kinds of stone tools that were smaller but could be used for many tasks and lasted for a long time. Archaeologists like me are interested in the Middle Paleolithic – a period spanning 250,000 to 30,000 years ago – because it includes the first appearance of our species, our arrival into many parts of the world for the first time, and our invention of many new kinds of stone tools. In our study just published in the Proceedings of the National Academy of Sciences, a team of international collaborators and I describe our discovery in China of the first complete example of a Middle Paleolithic technology previously seen only in Europe and the Middle East. Archaeologists have thought that ancient people in East Asia completely skipped the Middle Paleolithic. Our discovery challenges the long-standing notion that while ancient people in Europe and Africa were inventing new tools during this period, people of East Asia stuck to only the most basic tools that remained unchanged for thousands of years. The tool we've identified is called a Quina scraper. This type of stone tool is well known from archaeological sites in Europe and the Middle East. Quina scrapers are typically quite thick and asymmetrical, with a broad and sharp working edge that shows clear signs of being used and resharpened multiple times. This shape results in durable cutting edges, ideal for long cycles of use followed by resharpening. People used Quina scrapers to scrape and cut soft materials, such as meat and animal skins, and medium-hard materials, such as wood. We know this from tiny scratches and chips on the scrapers that match traces caused by working these materials in experiments using contemporary stone tools. European archaeologists believe that Quina scrapers were invented to meet the needs of highly mobile hunters living in cool and dry climates. These hunters were focused on seasonal migratory prey such as reindeer, giant deer, horse and bison. Quina scrapers would have helped them process their kills into food and other resources – for example, to extract marrow. Our team, led by Hao Li of the Institute of Tibetan Plateau Research and Qijun Ruan of the Yunnan Provincial Institute of Cultural Relics and Archaeology, excavated Quina scrapers and related stone tools from the Longtan archaeological site in southwest China. Our colleague Bo Li at the University of Wollongong used optical luminescence dating methods on the layers of earth that contained the artifacts. This technique can identify how much time has passed since each individual sand grain was last exposed to the Sun. Dating many individual grains in a sample is important because tree roots, insects or other animals can mix younger sediments down into older ones. After we identified and removed intrusive younger grains, we found the layers containing the artifacts were 50,000 to 60,000 years old. This is roughly the same time Quina scrapers were being used in Europe at Neanderthal sites. Keliang Zhao from China's Institute of Vertebrate Paleontology and Paleoanthropology looked at pollen grains from the Longtan excavations. He found that the Middle Paleolithic people of Longtan lived in a relatively open forest-grassland environment and a dry and cool climate. This environment is similar to that of Quina sites in Europe. Davide Delpiano, Marco Peresani and Marie-Hélène Moncel, experts on European Middle Paleolithic tools, joined our team to help with the comparison of the Chinese and European specimens and confirm their similarities. Hélène Monod, from Universidad Rovira i Virgili in Spain, looked at our Quina scrapers under the microscope and found traces on them from scraping and scratching bones, antlers and wood. She also found polish from using the tools on meat, hides and soft plants. Our new discovery of Quina scrapers joins another recent find of a different kind of Middle Paleolithic technology in East Asia: Levallois tools from Guanyindong Cave in Guizhou Province in south-central China. Levallois tools result from a distinctive multistep sequence that efficiently produces lots of useful cutting tools, with minimal wasted stone. Taken together, these two finds make a strong case that Middle Paleolithic technologies were present in East Asia. But why are we only just finding this Quina tool kit now, when it has been known in Europe for such a long time? One reason is that archaeologists have been looking in Europe for longer than almost anywhere else in the world. Another reason Middle Paleolithic evidence appears rare in East Asia is because what now seem to be less typical variations of the Quina tool kit previously found in China had been overlooked, likely due to archaeologists' narrow definitions based on European examples. The Quina tools at Longtan are among the earliest artifacts from that site, which makes it hard for researchers to determine the origins of this new technology. Was it introduced by visitors from Europe? Or did local people in East Asia independently invent it? To answer these questions, we hope to find more Quina scrapers at sites with deeper – meaning older – layers than Longtan. If older layers hold what look like the remnants of experiments in stone toolmaking that would eventually result in Quina tools, it suggests Quina tools were invented locally. If deeper layers have dissimilar tools, that suggests Quina technology was introduced from a neighboring group. We also hope future work will reveal who made these tools. Our excavations at Longtan did not find any human bone or DNA that could help us identify the toolmakers. During the Middle Paleolithic, there were multiple human species that could make tools like this. It could have been modern humans like us. But it could also have been Neanderthals. Considering that the Quina technology in Europe is directly associated with Neanderthals, this seems likely. But it could also have been Denisovans, an extinct species similar to modern humans found during this time in Siberia, the Tibetan Plateau and Laos, or even a new human species that hasn't been seen before. Whoever was making and using these Quina scrapers, they were able to be inventive and flexible with their technology, adapting to their changing environment. This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world. It was written by: Ben Marwick, University of Washington Read more: Ancient DNA is revealing the genetic landscape of people who first settled East Asia New dates for ancient stone tools in China point to local invention of complex technology Melting Mongolian ice reveals fragile artifacts that provide clues about how past people lived Ben Marwick does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
