How Did The Birds Evolve?

The revelation that birds originated from small carnivorous dinosaurs of the Late Jurassic period was made possible by newly discovered fossils from China, South America, and other nations, as well as by looking at existing museum specimens from new angles and using new technologies. 

The Search For The Evolution Of Birds

The search for the forebears of extant birds began in the early 1860s with the discovery of a representative of Archaeopteryx, the first known bird. It had feathers on its arms and tail like birds, but unlike live birds, it also had teeth and a long bone tail. 

Furthermore, unlike modern birds, the bones in Archaeopteryx’s hands, shoulder girdles, pelvis, and feet were not united and shortened. Based on these features, Archaeopteryx was identified as a transitional species between birds and reptiles, but which reptiles?

Paleontologists discovered Archaeopteryx shared characteristics with small carnivorous dinosaurs known as theropods in the 1970s. Except for the ornithischian dinosaurs, all of the dinosaur groups on this program are theropods. 

What Is the Hypothesis Based On The Similarities?

Based on these similarities, experts hypothesized that theropods were the ancestors of birds. Paleontologists were even more convinced after building evolutionary trees to investigate the matter. Birds are only twigs on the dinosaurs’ branches of the tree of life.

Many of theropod dinosaurs’ traits were altered as birds evolved from them. It’s crucial to understand that the animals were not “trying” to be birds in any way.


Indeed, the closer we examine, the more evident it is that the array of characteristics that distinguish birds evolved through a complex series of phases and served various functions along the way.

Take, for example, feathers. The first feathers were most likely developed by small theropods related to Compsognathus (e.g., Sinosauropteryx). Insulation was given by these short, hair-like feathers that sprouted on their heads, necks, and bodies. The feathers also appear to have had distinct color patterns; however, it is unclear whether they were for show, camouflage, species recognition, or another function.

Several additional forms of feathers have been discovered in theropods that are even more closely related to birds, such as the oviraptorosaurs. The one shown below is branching and downy. 

Others have developed a central stalk with unstructured branches emanating from it and its base. Others, like the dromaeosaurids and Archaeopteryx, had a vane-like structure with well-organized barbs that were held together by barbules. This is precisely like the feather structure of a real bird.

The Evolution of Feather Functions Has Long Been Questioned

As we’ve seen, the first, most basic, hair-like feathers clearly performed an insulative purpose. However, in later theropods, such as some oviraptorosaurs, the feathers on the arms and hands are long, even though the forelimbs are small. 

What Did These Creatures Do with The Long Feathers on Their Short Arms? 

One possibility stems from some spectacular oviraptorosaur fossils discovered in the Gobi Desert’s Cretaceous strata.

Like a brooding chicken, the animal’s skeleton is hunkered up in an egg nest. The hands are spread out over the eggs as if to protect their eggs. So these feathers may have fulfilled the purpose of warming the eggs and protecting them from danger.

In this article, we have learned about the evolution of birds. To know more about such answers, follow the website.

Was this article helpful?

Leave a Comment