Another clue to the origin of the birds
The discovery of a fossil bird the size of a raven, according to some scientists, clearly proves the close relationship between theropods (a certain group of extinct reptiles) and birds. It was discovered by an international team of paleontologists on the island of Madagascar. "This discovery is a wonderful example of how a fossil record provides the fundamental data for formulating, testing and revising ideas about the evolution of life," says Chris Maples, director of the National Science Foundation's Geology and Paleontology Program.
The bird fossil is 65 to 70 million years "Image" and dates from the late Cretaceous period. It was discovered in 1995 by an international team of paleontologists led by David Krause of the State University of New York (SUNY). The scientists have dubbed their find Rahona ostromi, meaning "Ostrom's threat from the clouds." Scott Sampson (New York College of Osteopathic Medicine) and Luis Chiappe (American Museum of Natural History in New York) are co-authors of the scientific paper published by Catherine Forster of SUNY in Science March 20. alt="
The Rahona has a long forearm bone and shows characteristics of well developed feathers. This indicates that he was able to fly. Unlike most birds, however, the Rahona also had a long, bony tail, as well as a large, crescent-shaped claw at the end of a thick second toe on the hind foot. This unique clawed toe is also found on a group of fast, predatory theropod dinosaurs called the maniraptorans. It is these maniraptoran dinosaurs (this group includes Velociraptor and Deinonychus) that many scientists believe birds evolved from. In Foster's opinion, this clarifies that birds descended from dinosaurs.
Forster added: "Rahona stands at the base of avian evolution, right next to Archeopteryx. It possessed feathered wings and many avian features on its hips and legs, including a foot that allowed it to perch like a bird on a perch. However, it also retained the large deadly claw of its theropod ancestors." Paleontologists have long suspected that birds evolved from theropods. This discovery lends a lot of weight to the idea that birds are a side branch of the theropod family tree," says Forster, at least.
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