Hummingbirds and birds-of-paradise are perhaps the most beautiful examples. They are recent groups, having evolved in the last 65 million years. Yet birds with bright colours and complex plumage did exist during the time of the dinosaurs. One such species has been recently discovered.
Unusually it came not from China, where so many Mesozoic avians have been located, but Brazil. At 115 million years old, the specimen was collected in 2011 from mid Cretaceous rocks in the Araripe Basin. The locality has yielded hundreds of fossil species, including plants, insects, fish, turtles and flying reptiles. This bird adds to its biological diversity.
|The fossil enantiornithine which clearly displays two long tail feathers|
|An artist's impression of the 115 million year old enantiornithine from Brazil|
During the Cretaceous, Earth's landmasses were grouped together into two super-continents: the southern Gondwana and the northern Laurasia. Previously all enantiornithine fossils came from Laurasia. This new species, however, would have inhabited Gondwana. This indicates that the group was global.
'We would have figured it out from the few fossils here and there, but this is really a great find. It's a whole new continent where enantiornithes were probably flying about,' said Richard Prum, a professor of ornithology at Yale University.
In bird evolution, the enantiornithine family came after the most primitive birds - creatures like Archaeopteryx and Confuciusornis. What their geographical location suggests is that birds underwent a rapid diversification during the Cretaceous, spreading from their ancestral homeland of Laurasia to Gondwana. Why has yet to be established, but a possible reason is the spread of forests after the decline of then giant Jurassic sauropod grazers. Large forested environments would have been prime centres for early birds to evolve and diversify, as their descendants would do in the last 65 million years with the recovery of the forests after the K-T boundary extinction.