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News Flash: Ungulates and Dinosaurs Together 80 million Years Ago (fwd)
I haven't seen this reported on the list, so thought I may as well do it
> Subject: News Flash: Ungulates and Dinosaurs Together 80 million
> Years Ago
> Hoofed Animals' Ancestors May Have Shared Earth With Dinosaurs
> by Associated Press, 24 May 1996
> WASHINGTON (AP) -- Ancestors of hoofed animals may have evolved
> during the time of the dinosaurs -- about 20 million years earlier
> than previously believed. An evaluation of tooth fossils found in
> 85-million-year-old sediment in Asia suggests they bear the marks of
> animals that grazed and could be from the ancestors of modern day
> horses, cows, elephants and other hoofed animals. The study, by
> J. David Archibald of San Diego State University, is to be published
> Friday in the journal Science. Experts said the finding suggests
> that the ancestors of hoofed, grazing animals called ungulates were
> present, at least in Asia, at the same time that dinosaurs were the
> dominate life form on Earth. Dinosaurs disappeared about 65 million
> years ago. The most popular theory has been that mammals were few in
> number and variety around then, but that the species quickly evolved
> over the following millions of years to fill ecological niches left
> vacant by the demise of the dinosaurs. But Archibald's findings
> suggest that the evolution of ungulates actually was well under way
> before the dinosaurs were gone. In his study, Archibald said that
> rat-sized tooth fossils recovered from the Bissekty Formation in
> Uzbekistan resemble the shape and characteristics of teeth found in
> animals that lived millions of years later. The teeth had the flat,
> squared grinding surfaces similar to what is found now in the teeth
> of herbivores. Archibald said that fossils from 65 million years ago
> show that the diversity of ungulates then alive led to eventual
> development of animals as varied as antelopes, whales and
> elephants. The teeth from Uzbekistan, he said, provide "evidence for
> rooting the ungulate radiation much farther back in time."
> Michael J. Novachek, curator of vertebrae paleontology at the
> American Museum of Natural History in New York, called Archibald's
> findings "pretty exciting stuff."
> "It really pushes back the time of origin for this line of animals,"
> he said. "The old notion that all placental diversity originated
> after the dinosaur was wiped out is starting to crumble a bit."
> Novachek said, however, that Archibald's ideas would be stronger if
> more complete skeletons from 85-million-year-old ungulate ancestors
> could be found.
> Science, which published the Archibald study, is the journal of the
> American Association for the Advancement of Science.
Thanks to Loren Coleman.
"Great - the blood-sucking Brady bunch!"