Africa is home to 2341 species of birds. Recently, a fossil of a dinosaur was found in South Africa. Fossils are the preserved bones of any animal, that normally lived hundreds of thousands of years ago. The first two statements seem very unconnected. However, there is a link between all those birds and the dinosaur. They are distant relatives!
The fossil that was found comes from a group of dinosaurs called Sauropods, and lived around 200 million years ago. This type of dinosaur had a long neck, four legs and a small head. Like birds, Sauropods also had hollow bones. However, the dinosaur was much bigger than any bird found today. It would have been around the size of two elephants when it was alive.
HOW ARE BIRDS RELATED TO SAUROPODS?
Birds evolved from another group of dinosaurs called Theropods. Theropods were related to Sauropods.
While it may be hard to believe that birds developed from dinosaurs, scientists have found evidence to prove this is true. Fossils of other dinosaurs have been found, that show how step by step, dinosaurs became birds. Scientists do this by working out how old the fossils they found are, and then putting them in a timeline. This way, they can track the order in which bird features developed in dinosaurs.
HOW DID DINOSAURS EVOLVE INTO BIRDS?
First, Theropod dinosaurs developed the ability to walk around on two legs, a big change from the Sauropods that used four legs to walk. Then, Theropods developed feathers, became smaller, and learnt how to fly, just like birds. The best example fossil that shows these changes comes from a dinosaur called the Archaeopteryx. This was a Theropod dinosaur that had feathers.
WHY DID THESE CHANGES HAPPEN?
All these changes to the dinosaurs happened very slowly. They started off as adjustments to features that already existed in the dinosaurs. The new features these changes caused made it easier for the dinosaurs to survive. For example, having feathers helped dinosaurs keep warm, making it easier for them to live in colder weather. The dinosaurs that survived those tough conditions could then pass on those new, birdlike features to their young. This is the natural process known as evolution.
Over time, all these features built up in the Theropod group, until they became the birds seen today, therefore birds really are living dinosaurs!