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July 29, 2000
Triceratops was a large, giant plant-eating dinosaur that had three horns on its head and a bony neck frill. Triceratops lived during the late Cretaceous period (about 72 to 65 million years ago) and was preyed upon by T. rex.
These scientists analyzed samples from two vertebrae and a rib fragment of a Triceratops from North Dakota, USA, isolating 130 base pairs of its 12S rRNA gene (ribosomal RNA, a type of RNA found in the ribosomes of cells, where protein synthesis occurs). 100% of the base pairs matched those of the turkey (and 94.5% were similar to many of the other bird RNA samples tested). If true, this find certainly strengthens the argument that birds and dinosaurs are closely related.
Dr. Garstka, from the University of Alabama, worked with scientists from the Russian Academy of Sciences and NASA to extract the RNA from the poorly mineralized samples. Most fossils are basically rock reproductions of the original organic tissue - over time, the original tissue undergoes the process of mineralization (in which the original atoms are replaced by new minerals, so a fossil doesn't have the same chemical composition as the original object). Poorly mineralized fossils, such as this one, retain some of their original organic material. It is this remaining organic material that was analyzed for genetic material.
This is an extremely controversial result, because most scientists think that nucleic acids (the organic material that DNA and RNA are made of) will not survive intact for over 100,000 years. Also, the birds are thought to have evolved from small theropod dinosaurs, and not ceratopsians (a type of ornithischian dinosaur), who diverged from the theropods (a type of saurischian dinosaur) almost a hundred million years before the first known bird (Archaeopteryx) appeared.
Dr. William Garstka reported this find at the Florida Symposium on Dinosaur Bird Evolution: Raptors, Rexes, Fuzz, and Feathers on April 8, 2000.
A page on Triceratops.
A page on the evolution of the birds.
A page on Archaeopteryx, the earliest-known bird.
A printout on the turkey
Other fossils found in the USA.
Chart of geological time.
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