Which came first? The chicken or the dinosaur? There hasn’t been a clear model of a birdlike creature evolving through the ages into the birds we see today. Yet, there have been a number of predecessors whose features clearly think them to modern birds.
In the late 1800s, Charles Darwin’s friend Thomas Huxley made the radical suggestion that birds are actually glorified reptiles. Recent discoveries have convinced many palaeontologists—scientists who study fossils—that this may be true. That means that dinosaurs, which disappeared 65 million years ago, and birds share a common ancestor.
225 Million Years Ago—According to recent discoveries, Protoavistexensis may have been the earliest bird. It had a wing structure that was far more advanced and efficient than the next type of bird that evolved millions of years later. Its hand bones show tiny nodes that may have been the location of feathers, although scientists don’t know for sure.
150 Million Years Ago—in 1861, German workmen splitting slate discovered a fossil of a winged, feathered creature about the size of a large pigeon. Scientists believe it probably used claws on all four limbs to climb around in trees and glided from one branch to another by using its feathered wings and tail. The fossil was named Archaeopteryx lithographica, which means “ancient wings written in stone.”
120 Million Years Ago—Many call Archaeoraptorlioningensis the strongest example of the “missing link” between dinosaurs and birds. In October 1999, scientists unveiled one in the form of a fossil. This foot-long dromeosaur belonged to the same family as the Tyrannosaurus rex.
80 to 85 Million Years Ago—the meat-eating dinosaur Velociraptor is thought to be another link in the evolutionary trail to modern birds. Like today’s birds, velociraptors had three functional toes, long arms with three-fingered hands, and half-moon shaped wrists for seizing prey. Velociraptor may have been covered in feathers—meaning that raptors in the movie Jurassic Park might have felt a little naked.
68 Million Years Ago—Like the Archaeoraptorlioningensis, the huge meat eater Tyrannosaurus rex was a dromeosaur. This shared family has led some to conclude that the T-rex’s young may have been covered in feathers, which they later lost. While these feathers may not have been used for flying, they would have helped in scaring away enemies. It seems the female of this species may have been larger than the male.
65 Million Years Ago—Most species of dinosaurs became extinct. Many of the bird species that had developed died out with the non-feathered dinosaurs. Also, the first modern birds, called the neornithes, developed. During the next few million years, the number and different kinds of birds increased astronomically—leading to the amazing variety of birds we have today.
54 to 38 Million Years Ago—The giant, flightless Diatrymasteini stood at 7.2 feet (2.2 meters) and wandered the forests of Europe and North America. And the direct ancestor of today’s vultures, Eocene neocathartes, soared through the skies. The rest of the neornithes continued to increase in number and variety.
Today—Many scientists believe modern birds are like feathered, short-tailed dinosaurs. Yet, birds have smaller jaws and no teeth. Their tail bones fused together and their forelimbs have changed into wings. And the size of their hind limbs has increased to help them walk on two legs. Migrating and nesting in trees also seem to be characteristics their dinosaurs ancestors did not have.