For several years scientists have been finding fossilized embryos of dinosaurs from 80 million to 100 million years ago. They have now uncovered several 190-million-year-old dinosaur embryos, the oldest ever found.
The discovery is being reported Friday in the journal Science by a team of paleontologists headed by Robert Reisz of the University of Toronto. The fossils were actually excavated in 1978 in South Africa, but it has taken this long to expose the embryos from the surrounding rock and eggshell and then interpret the tiny remains.
They identified the embryos as belonging to a long-necked, plant-eating dinosaur called Massospondylus. As adults, these creatures reached lengths of more than 15 feet and were able to walk on two legs. Yet the new research suggested that their hatchlings began life moving about on all fours, the scientists reported.
Dr. Reisz and his colleagues came to this surprising conclusion from a detailed examination of the horizontal neck, heavy head and limb proportions of the embryo skeletons. This appeared to mean that the young were quadrupeds and somehow matured into bipeds, a pattern of development, they said, that was almost unheard of among vertebrates.
"The results have major implications for our understanding of how these animals grew and evolved," Dr. Reisz said.
He was joined in reporting the research by other Toronto scientists and dinosaur experts at the National Museum of Natural History of the Smithsonian Institution and the University of Witwatersrand in Johannesburg.
James Clark, a paleontologist at George Washington University, who was not involved in the research, said the discovery was "exciting in providing a major piece of the puzzle" of how large plant-eating dinosaurs reproduced and, in at least one case, started life on four legs and grew to be two-legged animals.
The researchers also reported that the body proportions of the embryonic skeletons and an absence of well-developed teeth "suggest that hatchlings of this dinosaur may have required parental care."
So, will our buddy Rick Santorum insist that the embryos be implanted and brought to term because all life is sacred, or deny that anything could possibly be 190 million years old?
[img=right]http://www.tallguyz.com/imagelib/chmeesig.jpg[/img]My guess might be excellent or it might be crummy, but
Mrs. Spade didn't raise any children dippy enough to
make guesses in front of a district attorney,
an assistant district attorney, and a stenographer.
Sam Spade, "The Maltese Falcon" Operation Freedom Fry
Quadrapeds-Bipeds? Weird. Perhaps it has something to do with their hind-leg development, and how adults bulked up their thigh muscles.
"If one needed proof that a guitar was more than wood and string, that a song was more than notes and words, and that a man could be more than a name and a few faded pictures, then Robert Johnson’s recordings were all one could ask for."
wolveraptor wrote:Quadrapeds-Bipeds? Weird. Perhaps it has something to do with their hind-leg development, and how adults bulked up their thigh muscles.
What's with the wtf? Haven't you ever seen a baby that's too young to walk?
Cool. So, when can we make dinosaur omlets? Or, at the very least, get some dinosaur cloning going on? I mean, Jurrasic Park was supposed to take place in the '90s, right? We're behind the times.
wolveraptor wrote:Quadrapeds-Bipeds? Weird. Perhaps it has something to do with their hind-leg development, and how adults bulked up their thigh muscles.
What's with the wtf? Haven't you ever seen a baby that's too young to walk?
I would assume that that would only be the case within the first few days/hours of hatching. Almost every terrestrial bird, for example, has young that can walk quite soon after birth. Being stationary and vulnerable for too long would be detrimental to their survival. Ungulates are often in the same position.
On the other hand, I'm not aware of any large predators of Massopondylus. Maybe it wouldn't have needed to be on the move quickly.
"If one needed proof that a guitar was more than wood and string, that a song was more than notes and words, and that a man could be more than a name and a few faded pictures, then Robert Johnson’s recordings were all one could ask for."
Weird. Perhaps it has something to do with their hind-leg development, and how adults bulked up their thigh muscles.
