Why did the dinosaurs avoid the extinction of the three stacks?The answer was found

In the long geological history of the earth, five major biological extinction occurred. About 200 million years ago, a sudden disaster caused a large number of land organisms.

However, dinosaurs were lucky enough to escape this robbery and successfully "upper position", and in the subsequent Jurassic and Baiyu Ji of the world.

So, what causes the great extinction of land biology at the end of the three stacks? Why can dinosaurs survive in the natural disaster of biostatic and develop rapidly after the disaster?

On July 2nd, researcher Sha Jin Geng, Nanjing Institute of Geology, Chinese Academy of Sciences, and Dr. Fang Yaman cooperated with American scholars to publish the latest research results published online on the online "Scientific Progress". The main reason for the extinction of terrestrial creatures; the first revealing feathers with thermal insulation function and the climate that had already adapted to the cold of the polar ground was the reason why the dinosaurs avoided the three stacked volcano winter and quickly "upper".

In the equatorial area, the dinosaur's mouth was holding a base mammal. The background is the eruption of the Central Atlantic Super Fire Chengyan Province in the equatorial area of ​​the Panjia continent. The fur of the fur in the equatorial area has snowstorm in the volcanic winter. In

The intriguing Trippiece Biological Evolution

The Sanjie Period was the first period of the Middle -generation generation. It began to be 252 million years ago, ending 201 million years ago, and lasted about 51 million years.

Before the Triple Period, the Earth just staged a tragic life election. It took millions of remaining creatures to restore the earth's environment to the state where most creatures lived.

However, the stubbornness of life is beyond imagination. After experiencing the recovery and evolution after the end of the stack of the end of the Terminal, the creatures of the Triple Crane showed a prosperous scene. The climbing animals and the naked plants were unprecedented. It is particularly noteworthy that compared with the strange appearance of the paleon animals, the three stackers were triad. The climbing animals tend to look like modern creatures.

For example, trough, dinosaurs, and breastfeeding crawled animals rose rapidly in the Tri -Stack. By the late Triple Period, dinosaurs are already a variety of categories, occupying an important position in the ecosystem, and the Three Stacks are also called "dawn in the dinosaur era". However, the dinosaurs at that time were relatively weak, far from reaching the status of the king and the hegemony.

Although the triple -offs have made great efforts to repair the ecology of the earth and promote the evolution of life, nature still ruthlessly stepped on them: about 200 million years ago at the end of the Tri -Stacks, the ancient Panpan continent The drama of the environment has caused a new round of creature extinction.

虽然三叠纪末生物大灭绝的影响是5次大灭绝中最弱的，但还是有大量的海洋、陆地生物灭绝，比如海洋中的双壳类、腕足类、菊石、珊瑚、放射虫、 In -form, holes, etc., most of the non -dinosaurs, ancient lizards, animal hole climbing animals, and some large amphibians are also extinct.

However, this extinction also gives the special significance of the Triangle, that is, the only period of the Triple Permiars has experienced the era when they have gone out of the disaster and promoted the evolution of life. It has a profound impact on the development of the middle generation, especially the heyday of pioneering dinosaurs.

The ancient geographical location and dinosaurs distributed map of the Gargay Basin in the evening. Figures of the Nanjing Institute of Geology, the Chinese Academy of Sciences

Who is the culprit of the three stacks of extinction?

There have always been many interpretations of the causes of the major extinction of the three stacks. In recent years, the explorers have increasingly locked their attention on the volcanic eruption.

Scientists supporting volcanic eruption hypothesis believe that in the early middle of the middle generation, due to the disintegration of Pangu Pan continent, it caused strong volcanic activity, which caused the concentration of carbon dioxide to increase the concentration of atmospheric carbon dioxide and caused greenhouse effects.

Previous studies showed that at that time, the concentration of atmospheric carbon dioxide reached 1000-6000ppm, and there was no glacier on the earth.

However, Researcher Sha Jin Geng Geng, Dr. Fang Yen, and Professor Paul Olsen of Columbia University of the Chinese Academy of Sciences, Professor Paul Olsen University in the United States have different views on changes in the earth environment after the volcanic eruption.

They measured and studied high -resolution measurement of the Haojiagou in the Xinjiang Junggar Basin in the Xinjiang Junggar Basin.

The research team re -corrected the ancient latitude of the Junggar Basin and believed that it was located in the Arctic region of Panjia (about 71 degrees north latitude) in the Panjia continent. During the field inspection, for the first time, they found the exquisitely preserved dinosaur footprint fossils in the Junggar Basin to the early Jurassic Lake Marshal.

Sha Jin Geng told reporters that in the evening of the three stackers, herbivorous dinosaurs were mainly distributed in medium and high latitudes; low latitudes are mainly the first dragons of non -dinosaurs and non -primary dragons. After the three -stacking biological extinction incident, the dinosaurs spread quickly to the world; other new dragon animals that originally occupied low latitudes were performed.

The traditional point of view is believed to be caused by the global warming caused by the large amount of carbon dioxide released by volcanic eruption, but the response of land organisms after extinction seems to have denied this view.

The research team speculated that the super volcano eruption first brought volcanic winter. Volcano winter refers to the large amount of volcanic ash and gas solids released by volcanic eruption, which blocks the surface temperature caused by the earth's surface to block the surface temperature of the earth. Although the volcanic winter duration is shorter, it is only a few years to decades, and then the greenhouse effect is turned on, but it does not prevent the volcano's primary factor in "killing" most of the terrestrial creatures.

"If it is heating, land organisms will be migrated from low latitudes to high latitudes, but in fact, terrestrial four -legged animals, including dinosaurs, have migrated from high latitudes to low latitudes. The "cold 'in winter has caused the great extinction of land biology, not the" hot "that the traditional view is considered." Sha Jingeng said.

Why does dinosaurs survive in disaster

In the end of the tri -stacked biological extinction, dinosaurs are like the son of heaven. It not only laid the dominance of the world for itself, but also revitalized the dead chess of the entire ecosystem, as if all the sufferings on the earth were dominated by it for it for it. And the pavement.

Coincidentally, the research team found dinosaur footprints and ice raft deposits in the layer of the Junggar Basin to the early Jurassic world.

Ice rafts are deposited in sand or small gravel (0.1-15 mm in diameter) floating in mud rocks. Fang Yaman has two speculations about the deposition of ice rafts: First, because the lakes on the shore in the winter also frozen the gravel underwater when the water was frozen. When the spring flowers bloom, some ice cubes are like bamboo rafts. In the middle of the lake, it is melted in the mud. The other possibility is that the winter wind blows the gravel on the land to the ice surface, the ice of the spring lake melts, and the gravel falls into the bottom of the lake.

"This shows that even during the greenhouse and global period with no glaciers, seasonal freezing (below zero)," Fang Yaman said.

The characteristics of the Junggar Basin to the early dwarf are characterized by the dwarf -in -early Juraki world. Figures of the Nanjing Institute of Geology, the Chinese Academy of Sciences

Dinosaur footprints and ice rafts are deposited in polar areas, which means that the dinosaurs are very suitable for the severe cold climate of the polarity, and this is the "internal power" they survive the volcanic winter.

At the same time, these dinosaurs also have "outer" blessings.

"The branches of some non -bird beast feet dinosaurs and the two base -based grass -eating bird hips have found evidence of feather fossils. According to the system development bracket method, we infer that dinosaurs are born with feathers. These feathers are likely to be very likely It is used for insulation. "Fang Yaman said that although the large -scale adult dinosaurs currently discovered have no feathers, they may bring feathers when they are born. But the small elephant is hairy.

Primitive feathers with thermal insulation function ensure that grass -food dinosaurs can resist the cold winter of mid -high latitudes, and then enjoy the rich and stable plant resources of the middle and high latitudes.

Most of the first dragon -type animals without feather insulation are extinct in volcanic winter, and only a few small types of relatively small size are avoided in the cave and escaped the disaster.

All in all, the end of the three stacks leading to a large number of animals and plants, but inadvertently, the new and rising new troops of the dinosaurs opened the door to the earth. The top creature, and this position is 140 million years.

- END -