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Science
Friday > Archives
> 1998
> June
> June 26, 1998:
Hour One: Birds from Dinosaurs?
| It's a long-standing paleontological debate: are birds the descendants of dinosaurs, or did they evolve separately? Ever since the ancient bird Archaeopteryx was discovered back in 1861, the question has bothered the scientific community. The discovery of several new fossils, announced this week, may help settle the dispute - although some doubts are likely to linger. | 
Caudipteryx ( Model by Brian
Cooley; photo by O. Louis
Mazzatenta. © 1998 National Geographic Society)
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The newly discovered fossils, found in the Liaoning Province of China and discussed in this week's journal Nature and July's National Geographic Magazine, are of two different species of flightless dinosaurs - but the fossils appear to have feathers.
Those feathers, proponents of the dinos-to-birds theory say, help to cement their case. The feathers add the fossils, called Protarchaeopteryx and Caudipteryx, to a list of other dinosaurs having birdlike traits - a list that includes Sinosauropteryx, Unenlagia, and the star of Jurassic Park, Velociraptor. Supporters of the theory point to hollow bones, the presence of wishbones, and a similar hand design as more links between dinosaurs and birds. But some scientists who doubt the link cite other evidence - the fact that while both dinosaurs and birds have three "fingers," they have a different set of three; evidence that lungs may have been quite different in theropods and birds; and the difficulty of explaining how ground-dwelling creatures could have evolved to fly. They suggest that dinosaurs and birds may share a common ancestor, but that their similarities are the result of a separate but parallel evolution.
Join guest host David Baron for a look at the oldest paternity suit around - the debate over the origins of birds.
Above: Technician Kevin Aulenback, Canada's Royal Tyrrell Museum of Paleontology, and Caudipteryx zoui. (Photo by O. Louis Mazzatenta © 1998 National Geographic Society)
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Above: Close-up of the fossil of Caudipteryx. Feathers are especially visible on the animal's arms, seen in the center of the photograph. (Photo by O. Louis Mazzatenta © 1998 National Geographic Society)
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Above: Protarchaeopteryx robusta, found in northeastern China. The animal has more primitive feathers than the earliest known bird, Archaeopteryx.(Photo by O. Louis Mazzatenta © 1998 National Geographic Society)
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Above: Paleontologists Ji Qiang of China (standing) and Philip Currie of Canada (right) examine the fossil of Caudipteryx with technician Kevin Aulenback. Ji and Currie announced discovery of two new feathered dinosaur-like animals from China. (Photo by O. Louis Mazzatenta © 1998 National Geographic Society)
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Guests:
Philip Currie
Curator, Dinosaurs
Royal Tyrrell Museum of Paleontology
Drumheller, Alberta, Canada
Larry Martin
Professor, Systematics and Ecology
University of Kansas
Curator, Vertebrate Paleontology
University of Kansas Museum of Natural History
Lawrence, KA
Pat Shipman
Author, "Taking Wing: Archaeopteryx and the Evolution of Bird Flight"
Co-Author, "Wisdom
of the Bones"
Adjunct Associate Professor, Anthropology
Pennsylvania State University
State College, PA
Articles Discussed:
"Two Feathered Dinosaurs from Northeastern China," by Ji Qiang, Philip J. Currie, Mark A. Norell, and Ji Shu-An. Nature, June 25, 1998, pp 753-761.
"Dinosaurs Take Wing: The Origin of Birds" by Jennifer Ackerman. National Geographic, July 1998, p.74.
"Taking Wing: Archaeopteryx and the Evolution of Bird Flight" by Pat Shipman
Related Links:
National Geographic Society
Royal Tyrrell Museum
American Museum of Natural History
Dino Illustrations
University of California Museum of Paleontology |
