恐龙灭绝的原因 上面要中文 下面写英文 帮帮我 谢谢
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发布时间：2022-04-22 12:37
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时间：2023-11-04 18:27
Dinosaurs were all reptiles physical biggest category, very suitable for life in marshes and shallow lake, then the air warm and wet, the food is easy to find. So the dinosaur on earth millions years of rule, but somehow they 65 million years ago for a short time, and today people died out suddenly see only then leave of dinosaur fossils.
About the extinction of the dinosaurs reasons, people still constantly investigation. Long-term since, the most authoritative view of extinction of the dinosaurs and 65 million years ago a large meteors are concerned. According to research, there was a single diameter 7-10 kilometers asteroid crashed into the earth's surface, causing a huge explosion, send a lot of st thrown like the atmosphere, formation, resulting in the haze dec.15 plant photosynthesis temporarily stop, dinosaur thus destroyed.
An asteroid estimated theory, soon took many scientists support. In 1991, in Mexico's Yucatan peninsula found a occurred in bygone era of meteoritic impact craters, this fact confirmed this view. Today, this view seems to have into the verdict.
But there are also many people on this planet struck concerning skeptic because the fact is: frogs, crocodiles and many other sensitive to temperature animals have resisted the cretaceous and survive. The theory fails to explain why only dinosaur death ray. So far, the scientists suggest for the extinction of the dinosaurs imaginary has no fewer than a dozen reasons, comparative abound stimulating and dramatic "the meteorite collision said" is just one of them just.
Besides "the meteorite collision said" beyond, the main ideas about the extinction of the dinosaurs have the following kinds:
A, climate change said. 65 million years ago, the earth's climate change, and the temperature sudden drop considerably, causing the atmospheric oxygen levels drop, cause the dinosaur unable to survive. There are also people who believe that dinosaurs are cold-blooded, body without MAO or heat preservation organ, cannot adapt to earth temperature drop, all was frozen to death.
Second, species struggle said. The dinosaur of the 70s, initial small mammals appears, these animals of rodent carnivores, probably in dinosaur eggs for food. Owing to the lack of small animals, more and more natural, and finally ate the dinosaur egg.
Three, continental drift said. Geology research proves that existed around the time of the dinosaurs earth only a piece of mainland, namely "the ancient land". Due to earth changes, the continent in Jurassic happen larger division and drift phenomena, eventually leading to the environment and climate change, the dinosaur thus extinct.
Four, geomagnetic change said. Modern biology proof, some creatures of death and magnetic field are concerned. The biological magnetic field is more sensitive to the earth's magnetic field, change when, can cause extinction. By inference, the extinction of the dinosaurs may and the earth's magnetic field changes are concerned.
Five, the angiosperms poisoning said. The dinosaur of the 70s, earth gymnosperms disappearing, replaced by a large number of angiosperms, these plants containing gymnosperms lack of toxins, form a huge dinosaur appetite, thrashing intake angiosperms cause body endotoxin accumulation overmuch, finally be poisoned.
Six, acid rain said. The upper cretaceous period may once strong acid rain, soil including strontium, trace elements being dissolved, dinosaurs through drinking water and food directly or indirectly intake of strontium, appear acute or chronic poisoning, last batch
