In an expert review published in the same journal of Science magazine, internationally renowned paleontologist Allison C. Daley commented, "The Qingjiang biota is a shocking scientific discovery! Its fossil richness, diversity and fidelity are world-class, and its scientific value is enormous. Follow-up research will hopefully fill gaps in our understanding of cambrian explosions and address a range of scientific questions about the origin and evolution of animal phyla. ”
Science magazine published pages The images in this article are all provided by Northwestern University
To understand the significance of this discovery, we must first know about the "Cambrian explosion". In the Cambrian strata about 530 million years ago, geologists have found that it suddenly appeared in a series of animals such as arthropods, brachiopods, demodex, sponges, chordates and so on in more than 20 million years, and there are now 38 phylums in the animal kingdom on Earth, and in the fossils at this stage, 20 living animal phylums and 6 extinct animal phylums have been found, but there are still 18 living animal phylums that have not yet found fossil representation in the Cambrian period. To solve the mystery of the Cambrian explosion, in addition to scientific conjecture based on theory, it is necessary to discover the appropriate scientific observation window - the fossil library, in order to find reliable fossil evidence.
For more than 100 years, although more than 50 such fossil banks have been found around the world, according to the standards of the quality of fossil preservation and the diversity of fossil species, only the Burgess Shale biota in Canada and the Chengjiang biota discovered in Yunnan Province in China in 1984 have become "ideal top research destinations". In the 35 years since its discovery in Chengjiang, Yunnan, more than 280 species have been found in hundreds of thousands of fossil specimens, and it has become the only fossil site in China, a World Natural Heritage Site.
Of the 4,351 fossil specimens found, 109 genera have been classified and identified, 53% of which are new genera that have never been recorded before. Biometric "sparsity curve" analysis shows that the species diversity of the Qingjiang biota is expected to exceed the global known library of Cambrian soft body fossils, including Burgess and Chengjiang.
Limboli worm fossils
The Qingjiang biota is 1,050 kilometers away from the fossil origin of the Chengjiang biota, Zhang Xingliang introduced, "Biostratigraphic studies have shown that the Qingjiang biota and the Chengjiang biota are contemporaneous biota located in different paleo-geographical locations. Both date back about 518 million years, at the height of the emergence of animal phyla during the Cambrian explosion of life. The scientific research value of the two is highly complementary. Compared with the Chengjiang biota, the Qingjiang biota lives in deeper water environments far from the coast, representing new biomes in different ecological environments, as evidenced by more than half of its new genera species. Therefore, the subsequent large-scale excavations of the Qingjiang biota will provide first-hand materials for the discovery and exploration of new body configurations and new animal phyla. ”
At present, the world's two most fidelity Burgess shale-type fossil banks, Burgess and Chengjiang, have undergone serious geological modifications such as high temperature metamorphism and weathering after burial, and their samples have been unable to be used for in-depth burial research. The soft body fossils found in the Qingjiang biota miraculously preserved the original organic matter in the form of a native carbonaceous film, and there is no doubt that it will provide ideal material for burial and geochemical research, and then for in-depth paleoenvironmental research. The problem of special burial mechanism of animal soft body structure that has plagued the academic community for many years may be cracked in the Qingjiang fossil library.
A team in the Qingjiang exploration
Regarding the naming of the "Qingjiang biota", Fu Dongjing said that on the one hand, because the fossil burial site is at the confluence of the Qingjiang and Danjiang rivers, and more importantly, it is hoped that the Qingjiang and Chengjiang biota will become the world-renowned "China's Two Rivers Biota" in the future.
Geological discoveries and travel
The geological finds are actually very close to travel. There are many geological excavation sites in the world, or fossil discoveries, that have been listed as natural heritage sites and are open to the public, such as the Zigong Dinosaur Museum and the Dinosaur Park in Alberta, Canada, which are well-known sites and excavation site displays. For example, the "Chengjiang Biota" mentioned above, you can also visit it yourself.
The heritage site of the Chengjiang Biota is very close to Fuxian Lake in Yuxi, Yunnan, and there are two places to visit, one is the first site of the Chengjiang Fauna in the MaotianShan Mountains, where you can see the animal fossils under your feet up close through the glass compartment on the formation. The other is the Chengjiang Fossil Land Exhibition Hall in Chengjiang County.
On July 1, 1984, Mr. Hou Xianguang of the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences discovered a fossil of an early Cambrian invertebrate in the MaotianShan Mountains, and since then, geologists have found fossils of nearly 100 genera in 17 biological categories in ancient times.
Perhaps one day in the future, the Qingjiang biota will also step down from the cold scientific magazine in this way, so that more ordinary people can get close to this geographical discovery and experience the results of the unremitting efforts of this group of geologists for more than ten years, so as to learn more about the earth and human beings themselves.
Part of the content of this article comes from the official WeChat account of Northwest university "Northwestern University"