U OF L PROFESSORS CROSS DISCIPLINARY LINES TO LINK TEACHING, SCIENCE IN NATURE ARTICLE

LOUISVILLE, Ky. - A current and a former University of Louisville faculty member, both teachers of anatomy, have applied their knowledge of teeth and bones to fill in missing links about an ancient mammal relative of marsupials such as kangaroos. Their work is featured as the journal Nature's cover article Dec. 3.

Guillermo Rougier, a paleontologist who teaches anatomy to U of L dental students, and John Wible, a former associate professor who left U of L in September for the Carnegie Museum of Natural History in Pittsburgh, co-authored the article with Michael Novacek of the American Museum of Natural History in New York. Their research related to fossils, including teeth, jawbones and skeletal remains, found during the museum's annual paleontological expedition to Mongolia.

The bones belong to a marsupial relative called Deltatheridium, first identified in the 1920s. Early, sketchy information on the animal family came from a few poorly preserved teeth found in Asia. The new find -- 80-million-year-old fossils located at Ukhaa Tolgod, Mongolia -- contains remnants of several mammals in various growth and development stages, including one in the process of losing its baby teeth.

The excellent preservation of the fossils allowed Rougier's team to glean information which helped it to produce, for the first time, a comprehensive family tree of marsupials and their close fossil relatives, the Metatherians. (Modern marsupials include opossums, kangaroos and koalas.) The fossils also helped Rougier's team to zero in on the Deltatheridium family's evolutionary and geographic origins. Evidence unearthed in Mongolia indicates that Deltatheridium and other mammals were contemporaries of the dinosaurs. However, the family tree shows that, contrary to conventional wisdom, none of the now-living groups of marsupials was present when dinosaurs ruled the earth, Rougier said.

Rougier, an assistant professor of anatomical sciences and neurobiology, spent four years at the American Museum of Natural History before coming to U of L in September.

Rougier said he finds a natural affinity between paleontology, the study of fossils, and the anatomical science of human beings. Teeth are especially reliable clues because their enamel is the body's hardest substance; therefore, they leave a good fossil record which registers important changes in the evolution of mammals, he said. Teaching anatomy to dental students pulls the scientific branches together in his classroom, he added.

For more information, call Rougier, (502) 852-4541.

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