Essay on how dinosaurs evolved into birds

A major breakthrough in the origin of birds: Chinese scientists discover four-winged dinosaurs.

Although the hypothesis that birds originated from dinosaurs is supported by a large body of fossil evidence and systematics work, how birds first began to fly is a long-standing debate in the academic community. Xu et al. found that the dinosaur ancestors of birds had four wings and were likely capable of gliding in dinosaur fossil materials from Liaoning, China.

A well-known American ornithologist commented that the discovery of Xu Xing et al. is "the most important work in history" on the origin of birds, and the significance of this work is not only the origin of bird flight, but more importantly, because of this discovery, "paleontologists must re-evaluate some classical work".

Since dinosaurs were typically ground-dwelling animals, most paleontologists believe that the dinosaur ancestors of birds learned to fly while running on the ground. In 2000, Xu Xing et al. found that some dinosaurs had the characteristics of arboreal animals, and the dinosaur ancestors of birds may have used gravity in their arboreal life to gradually pass through the stages of landing and gliding, and finally mastered the powerful flapping flight ability.

Xu Xing said that through in-depth study of the ** structure on the dinosaur fossils of the Early Cretaceous in western Liaoning, China, they are convinced that these dinosaurs have preliminary flight capabilities. They found asymmetrical flight feathers on these dinosaurs, structures that are generally thought to be associated with flight. Most peculiarly, they found that these dinosaurs not only had their forelimbs feathered into wings, but their hind limbs also feathered into wings, that is, these dinosaurs had four wings.

While this morphology has not been found in any other vertebrate, scientists speculate that the dinosaur's hind wings may have played a balancing role during flight, which was important for early flight.

The discovery of four-winged dinosaurs by Chinese scientists was the first known dinosaur to fly, a discovery that has led to further confusion about how to define birds. Previously, scientists identified the ability to fly as the identification traits of the earliest birds, but the newly discovered dinosaurs belong to the class Bentosaurus, a typical small carnivorous dinosaur, suggesting that the line between birds and dinosaurs was more difficult.

I think dinosaurs become birds and they breed over and over again.

The body gradually becomes smaller, and it looks more and more like a bird, with hollow bones and a light body; skull enlargement, agile movement; Their forelimbs grew longer and longer, flapping like bird wings, and their bodies grew beautiful feathers, no longer covered with scales or scale armor.

Some of these species may migrate to trees to survive in order to escape predators or to find food. These arboreal dinosaurs jumped and landed from tree to tree, slowly gaining the ability to glide and eventually take their own flight.

The principle of pterosaur flight

The wing membrane structure that supported the flight of pterosaurs was completely different from the wing structures of vertebrates, birds, and bats that were able to fly later. Pterodactyls formed a wing surface from the epithelium, a membrane of muscles, and other soft tissues that stretched from the thorax to the extremely long fourth finger.

The membrane is supported by other phalanges. The membrane of the pterosaur was attached to only a slender finger that extended posteriorly along the side of the body to the knee; There is an additional epithelia between the neck and the arm. The front three phalanges are claw-shaped, slender hooks.

Its membranes appear to be fully adapted to flight and gliding, but are not as flexible and fragile as the membranes of bats or the wings of birds. The body is strong, with long, thin hind legs, the structure of which suggests that it is not adapted to vertical movement or rest, and is suspended by hind limbs when resting.

Summary. There is some basic consensus and evidence in the scientific community about the process of dinosaurs evolving into birds. However, if you want to make some hypothetical speculations, you can start with the following aspects:

What assumptions would you make about the evolution of a branch of dinosaurs into birds?

Good. There is some basic consensus and evidence in the scientific community about the chain infiltration process of dinosaurs evolving into birds. However, if you want to make some hypothetical speculations, you can start from the following aspects:

1.Morphological structure: Dinosaurs and birds have similarities in morphological structure.

Therefore, we can assume that as dinosaurs evolved into birds, they gradually developed a lighter, more flexible body structure, and gradually evolved characteristics such as feathers and wings. 2.Habits:

There are also similarities in the habits of dinosaurs and bright birds. For example, some small carnivorous dinosaurs may have adopted a jumping movement pattern, similar to that of modern birds. Therefore, we can assume that as dinosaurs evolved into birds, they gradually developed more efficient locomotion and predatory strategies.

3.Organ function: Dinosaurs and birds also have similarities in some organ functions.

For example, some dinosaurs had tooth shapes and structures that closely resemble the beaks of modern birds. Therefore, we can assume that as dinosaurs evolved into birds, they gradually developed respiratory, digestive, and nervous systems that were more adapted to aerodynamic principles.

The first dinosaurs on Earth during the Mesozoic Era appeared about 240 million years ago and eventually evolved into birds. "It's just a hypothesis, and scientists have speculated on this hypothesis that the dinosaurs didn't all go extinct.

Dinosaurs evolved from pseudocrocodiles to dinosaurs with hypophytosaurs, then further evolved into Archaeopteryx, and finally evolved into new birds.

Before 2004, the world thought that Archaeopteryx of the subclass Archaeopteryx was a bird discovered in the Jurassic, and in 2004 it was thought to be a dinosaur. From the specimens that have been found, it is inferred that Archaeopteryx is an intermediate link between reptiles and birds.

Since Darwin's origin of species, 100 years later, Chinese scientist Ji Qiang found three fossils in 1997, among which the tail feather bird fossil is the most convincing, in 1998 at the United States conference, and finally overwhelmingly said that birds evolved from dinosaurs, for the origin of birds to finally end.

Reduced body shape (hollow bones; skull swelling; Forelimbs are getting longer and longer) - feathers grow on the surface of the body - to survive in trees to avoid injury or find food—and have the ability to glide and fly.