Knowledge about dinosaurs?

Dinosaur (English name: dinosaur) is a reptile that appeared in Mesozoic (Triassic, Jurassic and Cretaceous). Its vigorous limbs, long tail and huge body are the portrayal of most dinosaurs. They mainly inhabit woodland or open areas in lakeshore plains (or coastal plains).

184 1 year, when British scientist richard owen studied several lizard-like bone fossils, he thought they were left by some prehistoric animals and named them dinosaurs, which means "scary lizards".

The sudden disappearance of dinosaurs at the end of Cretaceous 65 million years ago became a mystery in the evolutionary history of life on earth. This mystery has not been solved so far. In the past, all living things on the earth were recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata. A large number of bones or various shapes can be seen in it. However, in the subsequent Cenozoic strata, no fossils of non-bird dinosaurs were found at all, so it is inferred that non-bird dinosaurs died out together in Mesozoic.

There are many kinds of dinosaurs, and their shapes and habits are very different. The largest fragile double-chambered dragon may be more than 50 meters, while the smallest hummingbird may be less than 10 cm.

Extended data:

Two new dinosaur fossils, Uladeron and Shi Peng claw dragon, were found in the Gobi desert in northern China. This discovery helps to understand the evolution of dinosaurs.

These two newly discovered dinosaurs belong to Alvarez dinosaurs. In the early days, this dinosaur had three fingers and claws and long "grasping" forelimbs, which made it easy to hunt, but in the later period, it evolved short and stout forelimbs and single claws, which had the characteristics of early birds. Previously, their fossil records only included the most primitive taxa about 65.438+0.6 billion years ago and the progressive taxa after 90 million years.

The newly discovered two kinds of dinosaurs are just in the middle transition stage, which fills the gap in the fossil record in the evolution process. The evolution of limbs enables animals to adapt to the development in all directions and form rich and diverse species, which is one of the key research topics of biological evolution.

Although Alvarez's dinosaurs eventually became extinct on the road of evolution into birds, it provided a reference for us to understand the changes of dinosaurs in the food chain, that is, how to change from carnivores to insectivores.

Jonah Joner, a member of the research team and a professor of paleontology at the University of Witwatersrand in South Africa, believes that the evolution of Alvarez's dinosaur limbs may be related to the changes in its food. The giant single claw evolved by the late colony is likely to be used to dig and destroy rotten wood and ant nests and help them eat ants or termites inside.

Dinosaurs changed their staple food because of the change of the earth's environment and the intensification of competition.

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