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The following article was brought to my
attention by Peter Judge, who happened to come across my website recently. He
copied the article verbatum, but there is also a diagram posted, which you may
want to see,...kind of a crude phylogenetic diagram with pictures of
representative organisms. To get ther go to link below, then to "Todays
Contents", then to World news section, then article with same title as this
post:
Dear Larry,
Thanks for your email and your answers to my questions. I thought you'd be interested to read a copy of this article which appeared this morning (Friday June 23) in the London UK Times. The website is www.the-times.co.uk, but I've printed it across in full anyway. It shows a common FEATHERED ancestor for both birds and dinosaurs 220m years ago, dinosaurs descending from feathered 'dinosaurs' and a close relationship between birds and pterosaurs - although not quite as close in your theory. The article A SMALL reptile that glided through the trees in Central Asia 220 million years ago may have been the ancestor of birds, a group of American and Russian scientists has claimed. The lizard-like creature had feathers more like those of modern birds - a finding that contradicts the widespread belief that birds are the direct descendants of dinosaurs. At least 75 million years before the first true bird, Archaeopteryx, this four legged reptile was using its feathers to glide although it lacked the muscles to flap its wings to fly. One of the authors of the new theory, Alan Feduccia, of the University of North Carolina at Chapel Hill, is an expert on the evolution of birds who has never been convinced of their descent from dinosaurs. He believes that the ancient reptile, called Longisquama insignis, is powerful evidence in his favour. It is not a new find, having been discovered as long ago as 1969 by a Russian scientist in Kyrgyzstan, but it has spent much of the intervening period languishing in a museum drawer in Moscow. The initial identification suggested that the animal had scales not feathers. But last year the fossil was taken to the United States as part of a travelling Russian fossil exhibition and it was seen by John Ruben and Terry Jones of Oregon State University. "I had been asked to give a talk on dinosaur biology in a Kansas shopping mall, where this exhibit was," Professor Ruben said. "Terry Jones and I took one look at these fossils and we realised immediately that this was a very old animal with feathers. We stayed up all night in a vacant store in the mall to study it." The team reports in Science magazine that the creature has hollow shafted feathers almost identical to a modern bird's, used them for flight rather than for regulating body heat, probably used aerodynamic forelimbs for steering, and had a wishbone simular to that of modern birds today. "These are the earliest structures in the fossil record which can be called feathers," Professor Feduccia said. "They predate the so-called fuzzy dinosaurs from China by at least 100 million years." The reptile belonged to a group called archosaurs, from which birds and dinosaurs evolved. Dr Jones said, "We can identify certain structures in these fossils that you find only in feathers and just don't see anywhere else. So we are quite sure we are looking at the earliest feather. But beyond that, this animal looks like an ancestral bird even if you ignore the feathers. The teeth, pectoral structure, neck and skull are just like those of birds." Professor Ruben said that it was now questionable whether any feathered dinosaurs existed. "What have been called feathered dinosaurs were probably flightless birds," he declared. He pointed out that the most birdlike dinosaurs, such as bambiraptor and velociraptor lived 70 million years after Archaeopteryx. "Feathers are a very complicated structure," Professor Ruben said. "The odds of them evolving first in longisquama and then separately at some later point in dinosaurs, or any other group of animals would have been astronomically small." To Professor Feduccia, the implications are clear: birds cannot have descended from dinosaurs because the features that characterise them were already established before the dinosaurs appeared. "But just as you can't be your own grandmother, birds can't have come from dinosaurs, birds can't have come from therapod dinosaurs because the fossil record shows the timeline all wrong," he said. Best wishes and thanks for your time Peter Judge |