China News Service reporter: Sun Zifa
2024 is the traditional Year of the Dragon for the Chinese nation. What is the connection between the dragon in the Year of the Dragon and the extinct dinosaurs, pterosaurs, ichthyosaurs, etc. that once dominated the earth's land, sky, and oceans hundreds of millions of years ago? What is the discovery and distribution of its fossils? How many mysteries have been revealed by relevant research? What are the other unsolved mysteries?
On the occasion of the New Year in the Year of the Dragon, three paleontologists from the Institute of Vertebrate Paleontology and Paleoanthropology (Institute of Vertebrate Paleontology), Chinese Academy of Sciences (Institute of Vertebrate Paleontology), including Academician Xu Xing, Researcher Wang Xiaolin, and Researcher Li Chun, accepted an exclusive interview with China News Service's "East-West Question" to discuss dinosaurs, Popular science interpretation of research on pterosaurs, ichthyosaurs, etc.
They emphasized that, except for the fact that their names contain "dragon", the dragons in the Year of the Dragon have nothing to do with the dinosaurs, pterosaurs, and ichthyosaurs that dominated the land, sky, and sea in the Mesozoic Era during the ancient geological period. They hope that taking the spotlight on the "dragon" topic in the Year of the Dragon as an opportunity, people will pay more attention to basic research on dinosaurs, pterosaurs, ichthyosaurs and other paleontology, as well as the environmental changes and ecological evolution of the earth over the long history and its impact on the earth. and its impact on the future of humanity.
Video: [East-West Question] Talking about dragons in the Year of the Dragon, what is the mystery of the three dragons of land, sea and air hundreds of millions of years ago?
Source: China News Network
The interview transcript is summarized as follows:
Reporter from China News Service: According to current research, what kind of animals were the dinosaurs, pterosaurs, and ichthyosaurs of the Mesozoic Era? What is their classification and fossil distribution?
Xu Xing:
Dinosaurs are a type of reptiles that mainly lived on land in the Mesozoic Era. When scientists first discovered dinosaur fossils in 1677, they realized that dinosaurs were very large (of course, small dinosaurs were also discovered later). When they named dinosaurs in 1842, Its original meaning is "terrible lizard", referring to the fact that they are a type of huge reptiles that are very different from modern creatures.
Dinosaur fossils are distributed and found in major continents around the world, including the United States and Canada in North America, Argentina in South America, China and Mongolia in Asia, Tanzania, South Africa and Madagascar in Africa. Currently, there are about 2,000 named dinosaur species around the world, of which more than 1,000 can be confirmed, while others are controversial. China has named more than 300 species of dinosaurs, about a quarter of which may also be controversial. In terms of the number of dinosaur species, China ranks first in the world.
The first dinosaur excavated, studied and mounted by the Chinese themselves - Lufengosaurus Xu's fossil is displayed in the China Paleozoology Hall of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences. Photo by Sun Zifa
Wang Xiaolin:
Pterosaurs are a very strange and mysterious flying reptile. They are also the first vertebrates to take the initiative to fly into the blue sky. Pterosaurs are not flying dinosaurs. The two belong to different taxa, but they are closely related and are equivalent to "cousins" of humans.
Currently, there are only three known active flying vertebrates on Earth: pterosaurs, birds and bats. Pterosaurs were the first to fly into the blue sky, and they are also the only ones among the three that are extinct. Their slender, hollow bones are very similar, but their morphological structures are very different.
Ecological restoration map of the friendly and beautiful flying dragon (Pterosaurus). Drawing by Zhao Chuang, photo provided by interviewee Wang Xiaolin
Scientists have been studying pterosaur fossils since 1784, but it was not until 100 years later that basic understanding was achieved, and there is still some controversy. Pterosaurs have slender and hollow bones due to the need for flight. This makes pterosaur fossils very rare and mostly incomplete around the world because they are difficult to preserve. At present, pterosaur fossils are mainly found in China, Germany, Italy, the United Kingdom, Kazakhstan, the United States and Brazil. There are more than 200 officially named genera and species. More than a quarter of them have been found in China, which should be the most discovered pterosaurs in the world. s country.
Li Chun:
The marine reptiles named dragons in the Mesozoic Era mainly include ichthyosaurs, pterosaurs, and a small group of sea dragons, protosaurs, and part of the archosaurs. Just as pterosaurs are not dinosaurs that fly in the sky, ichthyosaurs are not dinosaurs that swim in the water, but a type of marine reptiles.
During the Mesozoic Era, there were many marine reptiles, and the largest groups were ichthyosaurs and pterosaurs. According to current research and understanding, they live in the ocean throughout their lives, and their reproduction and birth processes are completed in the sea, just like today's mammal whales.
Fossils of Ichthyosaurus from Panxian County, Guizhou Province, displayed at the China Paleozoology Hall of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences. Photo by Sun Zifa
Fossils such as ichthyosaurs and pterosaurs are mainly distributed in three places around the world: the first is Europe with the Alps as the core, spreading to the south and west; the second is southwest China with Yunnan and Guizhou provinces as the core. It is also found in Hubei, Anhui, Tibet and other places; the third location is in the Rocky Mountains on the west coast of North America.
Fossil genera and species such as ichthyosaurs and finosaurs are mostly named according to their morphology. There are currently more than 100 species in the world and dozens in China.
Fossils of Oulosaurus (pteryxosaur) in Xingyi, Guizhou, displayed at the China Paleontology Museum of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences. Photo by Sun Zifa
China News Service reporter: What mysteries have been revealed so far in the research on dinosaurs, pterosaurs, and ichthyosaurs? What are the representative results?
Xu Xing:
First of all, scientists have realized and confirmed through research that animals like dinosaurs once existed on the earth. This is the most important foundation for dinosaur research. Secondly, the paleontological community proposes that dinosaurs were warm-blooded and were endotherms, more like living birds and reptiles. Third, regarding the mass extinction of dinosaurs in the Cretaceous, academic circles now generally believe that the main cause of the extinction of dinosaurs was the impact of asteroids on the earth, and volcanic activity on the earth during the same period also played a supporting role.
In addition, scientists have realized the genetic relationship between dinosaurs and birds, and the hypothesis that dinosaurs evolved into birds has now become a mainstream hypothesis in the paleontological world. Regarding the question of how dinosaurs evolved into birds, the discovery of feathered dinosaur fossils in China since the 1990s has made the greatest contribution. On the one hand, it shows how feathers evolved from dinosaurs, and on the other hand, it also reveals how dinosaurs evolved to fly. ability.
Fossils of Millennium Sinornithosaurus (a ferocious feathered dinosaur) displayed at the China Paleozoology Hall of the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences. Photo by Sun Zifa
Wang Xiaolin:
China has many important pterosaur fossil origins. A large number of well-preserved pterosaur fossils have been found in the Jehol Biota, Yanliao Biota and Xinjiang in the surrounding areas of western Liaoning. After the discovery of the "Pterosaur Eden" in Hami, research suggests that in the Early Cretaceous, about 120 million to 130 million years ago, Hami and Urho areas, which are now located in the north and south of the Tianshan Mountains, were lakes, and pterosaurs lived in groups and flew around the lakes. , fish, lay eggs, and reproduce.
The Hami Gobi Yadan Formation has multiple layers rich in pterosaur fossils, indicating that many catastrophic storm events occurred in the large lake environment at that time, resulting in the death of pterosaur colonies. It is estimated that each layer contains tens of millions of pterosaur individuals. Hami's "Pterosaur Eden" also discovered symbiotic large sauropod fossils, as well as theropod teeth and footprints and other fossils, which not only increased the diversity of Hami's pterosaur fauna, but also increased the number of early Cretaceous sauropods in China. Diversity and geographical distribution of dinosaurs.
In addition to the important progress made in a series of researches such as the discovery of a large number of male and female Hami pterosaurs in Hami's "Pterosaur Eden" and the world's first three-dimensionally preserved pterosaur eggs and embryos, the world's first pterosaur was also discovered in the Jehol Biota. Pterosaur egg and embryo fossils, the world's smallest pterosaur "Hermit Forest Pterosaur", a key link in the evolution of pterosaurs "Wukong Pterosaur", etc. In addition, the research results in the past two years also include proposing a new view of the "North China Craton Pterosaur" of the Jehol Biota, naming the "Friendly and Beautiful Flying Dragon" to commemorate the 20 years of friendly cooperation between Chinese and Brazilian scientists, etc.
The fossil of the world's smallest pterosaur, the Hermit Forest Pterosaur, discovered in China, and its restoration. Photo by Sun Zifa
Li Chun:
Studies have shown that ichthyosaurs were ovoviviparous, which is different from the viviparous mechanism of mammals and the laying of eggs by dinosaurs and pterosaurs. Ichthyosaurs do not lay eggs. Their eggs are hatched directly in the belly, and they are born as babies. Ichthyosaurus.
More than half a century ago, an older generation of scientists discovered fossil materials of "Himalayan Ichthyosaurus" during scientific expeditions in Qinghai-Tibet. On this basis, in 2023, the Tibetan scientific expedition team of the Institute of Vertebrate Paleontology, Chinese Academy of Sciences, once again discovered and confirmed Himalayan ichthyosaur fossils in the Triassic strata of the Tibetan Plateau.
China News Service reporter: What important contributions have China and Chinese scientists made in the research fields of dinosaurs, pterosaurs, and ichthyosaurs?
Xu Xing:
Feathers and flight are the two most important characteristics of birds. The earliest and most discovered feathered dinosaur fossils in China have made a very important contribution to the study of the evolution from dinosaurs to birds.
China has discovered a large number of dinosaur fossils, ranking first in the world by species. Although in the early evolutionary stage of dinosaurs in the Triassic, only scattered dinosaur footprint fossils have been found in China, and clear dinosaur bone fossils have not yet been discovered, the concentration and large number of dinosaur fossils discovered in China's Jurassic and Cretaceous periods have played a vital role in the rise of dinosaurs and the development of dinosaurs. They have made great contributions to the study of how they flourished and how they evolved into birds. In addition to the evolution of dinosaurs into birds, the early fossils of the ceratopsian family among dinosaurs were basically discovered in China, and some of the earliest members of the Stegosaurus family were also discovered in China.
In summary, in the past two to three decades, a series of important discoveries and research, especially feathered dinosaur fossils, have made China undoubtedly one of the centers of dinosaur research in the world, and can also be said to be the most important region.
Wang Xiaolin:
In recent years, the discovery and research of a large number of pterosaur fossils in China have attracted much attention, especially the discovery of the Cretaceous "Pterosaur Eden" in Hami, Xinjiang - the largest and richest pterosaur fossil origin known in the world so far. and research, allowing the academic community to learn more about pterosaurs. At the same time, pterosaur eggs and embryos were discovered and three-dimensionally preserved for the first time in the world, providing important fossil evidence for a comprehensive understanding of pterosaur reproduction, growth and development. These are considered to be one of the most important and exciting discoveries in more than 200 years of pterosaur research, helping to unravel some mysteries of pterosaur evolution.
Researcher Wang Xiaolin (left) and research team member Associate Researcher Jiang Shunxing jointly display the fossil type specimen of the friendly and beautiful flying dragon (pterosaur). Photo by Sun Zifa
Chinese scientists also discovered that pterosaurs were hairy, and the early hair-like structures were very similar to the primitive feathers on dinosaurs, which were designed to dissipate heat and keep warm. Most living reptiles are cold-blooded ectotherms. Most scientists believe that pterosaurs are warm-blooded endothermic animals. Like birds and humans, they have a constant body temperature to ensure that their flight is not greatly affected by changes in the external climate environment. In addition, research has found that pterosaurs mainly eat fish to obtain enough nutrition to fly in the blue sky.
Li Chun:
There are three main geographical regions of marine reptiles in the world. The Chinese region has caught up from behind and currently has the most abundant fossil materials and genera and species. Since the 21st century, a large number of marine reptile fossils have been discovered explosively in China, including many new categories, genera and species. The number and types of fossils exceed those in Europe and the United States.
Among them, the new discovery of Himalayan ichthyosaur fossils has important significance and far-reaching impact on understanding the environmental changes of the Qinghai-Tibet Plateau.
Reporter from China News Service: What are the unsolved mysteries in the study of dinosaurs, pterosaurs, and ichthyosaurs? What significance does these basic research have for the human world today and in the future?
Xu Xing:
The unsolved mysteries of dinosaurs or the focus of follow-up research mainly include: why some dinosaurs grew to giant sizes; when did the earliest feathers appear in the process of dinosaurs turning into birds, and how far the feathers were distributed; how did dinosaurs evolve? Whether the ability to fly has a single origin or multiple origins; dinosaurs are not like typical reptiles, but more like endotherms. From a physiological point of view, what kind of creatures are dinosaurs? How did dinosaurs become the dominant animal group on the earth?
Gigantoraptor (dinosaur) restoration picture. Drawing by Zhao Chuang, photo provided by interviewee Xu Xing
Research on biological evolution must carry out global comparisons. Dinosaur research has been an international subject from the beginning, and solving unsolved mysteries must be carried out through international cooperation. Recently, scientists from China, South Africa, Argentina and North America are discussing jointly launching an international large-scale scientific plan for dinosaur cooperation. In addition, the application of big data, artificial intelligence, etc. to initiate the implementation of the Deep Digital Earth (DDE) project will promote the online sharing of data and knowledge in the history of the earth, which can not only promote global dinosaur research cooperation, but also better promote science to the public. .
The significance and impact of the study of dinosaurs and other paleontology includes at least two levels: first, basic science itself, where humans are driven by curiosity and want to understand the mysteries of nature and the universe; second, "taking history as a mirror and using history as a mirror" to study historical periods Biodiversity, ecosystem changes, etc. can provide some reference for the future development of humans and the earth.
Wang Xiaolin:
There are still many unsolved mysteries about pterosaurs, and there is an urgent need for Chinese and foreign paleontologists to work together to carry out research. In addition to macroscopic research on the morphology of pterosaur fossils, more sophisticated microstructure research must be carried out with the help of new technical methods. For example, through in-depth research on pterosaur eggs, embryos, and hair-like structures, we can reveal the secrets of pterosaur reproduction, embryonic and individual development, and the evolution of the entire group.
The three-dimensionally preserved pterosaur egg fossil discovered by Wang Xiaolin's research team in the "Pterosaur Eden" in Hami, Xinjiang. Photo by Sun Zifa
During the field scientific expedition and research in the Hami Gobi, some mysteries have been discovered that need to be solved. For example: we think that pterosaurs ate fish, but so far, no fish fossil has been found in Hami's "Pterosaur Eden", and there are no scales or vertebrae; We found that Hami pterosaurs are more closely related to some pterosaur groups in the Jehol biota of western Liaoning, but are more distantly related to the geographically closer Junggar pterosaurs.
In addition, the pterosaur fossil assemblage in China is very similar to that in Brazil. Comparative research on pterosaur fossils between continents will hopefully reveal the paleogeographic distribution of Mesozoic pterosaurs around the world, as well as how they migrated, spread and communicated.
Li Chun:
Personally, I feel that the research on ichthyosaurs and other marine reptiles has not solved the "substantial" mystery so far. In the future, more conclusive fossil evidence will be used to gradually reveal the secrets. The main research content includes: when did ichthyosaurs, finned dragons, etc. originate? Which groups are most closely related to them; whether ichthyosaurs are cold-blooded or hot-blooded, how to maintain body temperature in the ocean, how to regulate movement and various body functions, etc. These series of questions should be future research directions.
As for the practical significance of relevant research, it reminds us to cherish every day. Compared with the history of the evolution of the earth, life in nature is insignificant. There have been many mass extinctions in the history of the earth, which makes people feel the infinite mysteries of the earth and the insignificance of human beings. , life is short.
Interviewee profile:
Xu Xing. Photo by Sun Zifa
Xu Xing, an academician of the Chinese Academy of Sciences and a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, has long been committed to the study of dinosaur evolution and dinosaur taxa. He has published more than 300 papers and was selected as a national candidate for the "New Century Hundreds and Thousands of Talents Project" , the first batch of leading talents in tens of millions of projects under the "National Special Support Plan for High-Level Talents". He is currently the scientist who has discovered and named the most dinosaurs in the world, so he is known as the "Dinosaur Academician" and the "Chinese Star" in the world of dinosaur research.
Wang Xiaolin. Photo by Sun Zifa
Wang Xiaolin, corresponding academician of the Brazilian Academy of Sciences, researcher at the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, university professor and doctoral supervisor of the Chinese Academy of Sciences, winner of the National Outstanding Youth Fund; executive director of the Chinese Society of Paleontology and Society of Vertebrate Paleontology, and Chinese Popular Science Writers Association Executive director, chairman of the Special Committee for the Integration of Science, Film and Television, and member of the National Expert Committee on Paleontology and Fossils. Mainly engaged in research on pterosaurs, dinosaurs, dinosaur eggs and other fossils and related geology, and has presided over dozens of large-scale field scientific expeditions and fossil excavations; the results have been selected into the top ten scientific progress news in China, the top ten progress in Chinese paleontology, etc., and have been awarded by China The Science and Technology Achievement Award of the Academy of Sciences, the Second Prize of the National Natural Science Award, the Advanced Individual in Science Popularization Work of the Chinese Academy of Sciences, and the Yang Zhongjian Science Communication Award, etc.
Li Chun. Photo by Sun Zifa
Li Chun, a young scientist who is mainly engaged in the study of Triassic marine reptile fossils in China and a researcher at the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, has made many field trips to Guizhou, Yunnan, Hubei, Guangxi, Tibet and other places. So far, he has discovered relevant There are more than 60 important fossil sites of the ridge fauna, and more than 200 Triassic marine reptile fossils have been collected, establishing the most complete and exquisite collection of such specimens in the world. Since 1999, he has chaired many National Natural Science Foundation projects and major directional projects of the Chinese Academy of Sciences. He has published more than 50 papers and won the Lu Jiaxi Young Talent Award of the Chinese Academy of Sciences, the Young Paleontology Award of the Chinese Society of Paleontology, the Yang Zhongjian Science Communication Award, and the Chinese Geology Award. The society’s top ten scientific and technological achievements of the year and other awards.
(China News Service WeChat official account)