Feathered Dinosaurs
Posted August 1, 1998
The next time you see a robin tugging a worm out of the ground, you can be certain that the bird is a descendent of a meat-eating, two-legged, running dinosaur called
a theropod. In 1996 an important fossil find was made in China. A fossil theropod with downy fibers, Sinosauropteryx, was discovered. Some scientists think that the downy fibers
could be the forerunners of true feathers. But, other scientists argue that the fibers were probably just reptilian frill rather than feathers.
In 1998, two new fossil discoveries in the same area of China provided more evidence to support the evolution of birds from dinosaurs. These theropod dinosaurs had
plumage identical to bird feathers. They had down-like feathers and feathers with parallel barbs running down opposite sides of a central shaft. In spite of the fact that these fossils
had bird-like feathers, they were not birds.
Theropods lack a number of features seen in Archaeopteryx, the first true fossil bird. Also, it is unlikely that these fossil theropods, Protarchaeopteryx
robusta and Caudipteryx zoui, could fly. They had a body the about size of a turkey, short forelimbs, and short feathers shaped like those of modern flightless birds.
Scientists think that the feathers of theropod dinosaurs provided insulation or camouflage. Courtship display, similar to that of a modern peacock, was another possible
use for the feathers.
Think Critically: Why was the discovery of feathers on theropod dinosaurs was so important in determining that they were the ancestors of modern birds.
References
Ackerman, Jennifer. "Dinosaurs Take Wing." National Geographic, 194(1), pp. 74-99.
Monastersky, R. "Feathered Dinosaurs Found in China." Science News, 153(26), June 27, 1998, p. 404.
Padian, Kevin. "When is a Bird Not a Bird?" Nature, June 25, 1998, pp. 729-730, 393.
Padian, Kevin, and Luis M. Chiappe. "The Origin of Birds and Their Flight." Scientific American, 278(2), Feb 1998, pp. 38-47.
Qiang, Ji, Phillip J. Currie, Mark A Norell, Ji Shu-An. "Two Feathered Dinosaurs from Northeastern China." Nature, June 25, 1998, 393, pp. 753-761
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