Posted on 06/02/2005 2:06:01 PM PDT by dread78645
WASHINGTON (Reuters) - A Tyrannosaurus rex dinosaur that died 68 million years ago has provided some of the strongest evidence yet that birds are the closest-living relatives of dinosaurs, scientists said on Thursday.
Soft tissue found in the animal's thighbone strongly suggests it was a female, and just about to lay eggs, the researchers report.
The bone tissue is strongly similar to that made inside the bones of female birds -- and no other living type of animal -- when they are producing the hard shells of eggs just before they lay them, said Mary Higby Schweitzer of North Carolina State University in Raleigh.
"In addition to demonstrating gender, it also links the reproductive physiology of dinosaurs to birds very closely. It indicates that dinosaurs produced and shelled their eggs much more like modern birds than like modern crocodiles," Schweitzer told reporters in a telephone briefing.
Female birds produce a layer of bone tissue called medullary bone when they are laying eggs. It is rich in calcium, providing minerals that would otherwise be leached from harder bone material, leaving the bird susceptible to fractures.
"The way that crocodiles lay and shell their eggs is they hold them in their reproductive tract and shell them all at once," Schweitzer said.
"Birds shell their eggs one at a time as they move down through the reproductive tract. It is a pretty calcium-intensive process."
ALREADY A STAR
This particular T. rex fossil made headlines in March when the same team of paleontologists reported it contained preserved soft tissue -- the first ever found in a dinosaur bone.
"The reason that we have found all the things in this one particular animal is this specimen was in a very remote part of Montana, in the Hell Creek formation," said Jack Horner of the Museum of the Rockies and Montana State University.
"It was so far out in the country that we needed to helicopter it out and we actually had to split the thighbone into two pieces to get it into the helicopter."
When Schweitzer unwrapped the cracked-open femur she immediately saw the soft tissue and went to work proving its remarkable state of preservation.
Horner plans to crack open some other bones.
"We have 12 specimens of Tyrannosaurus rex here at this institution, and we are about to find out if any more of them are females, just by looking inside," he said.
It was a stroke of luck to find an animal at just the right stage to be making medullary bone, Schweitzer said.
"It would not be present in a brooding animal," she said.
"But it would be present as long as there was an egg left to lay. The animal was probably near the end of its laying cycle."
Finding another such specimen will be difficult.
"I think it is pretty much a long shot," she said.
In April, Tamaki Sato of the Canadian Museum of Nature in Ottawa, and colleagues reported they had found the fossil of a dinosaur in China that carried two eggs in its body.
Its physiology also was closer to modern birds than to modern crocodiles, Sato reported.
Horner said most experts are convinced the two-legged dinosaurs known as theropods were closely related to living birds.
"This is another piece to the puzzle and there are a lot of them," he said. "Anyone who would argue that birds and dinosaurs are not related -- frankly I'd put them in the Flat Earth Society group."
"Anyone who would argue that birds and dinosaurs are not related -- frankly I'd put them in the Flat Earth Society group."
Who the heck cares anyway?? So birds are related to dinosaurs. We're the same species as Janet Reno.
Little brown dots in the "T-rex" tissue and Little brown dots in the Ostrich tissue = they are the same.
You mean those weren't leftover cornflakes???
This fossil, along with the 100 mpg carburetor, the remains of Noah's Ark, and the Shroud of Turin, were all kept hidden away by those eeeeevvvviiillll scientists, who want to ... well, to do bad things.
They're hidden away in a government warehouse next to the Ark of the Covenant. I thnk it was Harrison Ford who told me that.
What confirmation more does one need than one's faith?
I predict that the sun will come up tomorrow.
She spoke: "Males have one fewer pair of ribs than females."-- Darwin's Rib
I was totally unprepared for her answer. My mandible dropped. After a moment's reflection, I realized she must be referring to the biblical story in which God creates Eve from one of Adam's ribs. My student was someone who believed in the literal truth of the Bible, and it was her religious belief, not her previous knowledge of human anatomy, that made her so sure of her answer. This was going to be a challenge.
...
THESE DAYS I'M BETTER PREPARED than I was that first year. Sometimes I bring in an extra pair of skeletons or a medical textbook with X-ray photographs of the chest, so that the students can count ribs to their hearts' content. I've come to expect at least 10 percent of the students in each class to tell me that men and women differ in rib count. I have conducted surveys of nearly a thousand first-year college students who either are nonscience majors or have not yet declared a major. More than 25 percent report believing that God created the Earth within the last 10,000 years and that man was formed in God's image exactly as described in the Bible. Another 50 percent report being undecided as to whether evolution is a valid scientific theory or a hoax. Only about 20 percent enter my university having learned enough about science and the evidence for evolution to consider it a valid scientific theory.
...
But I always have the last laugh. I share it with my classes after they have counted ribs for themselves and know for themselves the correct answer. You see, I really do have one fewer pair of ribs than my mother.
Don't get me wrong: I'm perfectly normal. I have 12 pairs of ribs, just like almost every other human being, male or female. So, as far as we know, do my father and brother. My mother is the unusual one. She has 13 pairs of ribs.
Oh yes, and that 5,300-year-old man they found frozen in a glacier in the Alps a few years back? He's got only 11 pairs of ribs. It happens. Still, imagine what might happen if the creation "scientists" get hold of a replica of the 5,300-year-old man's skeleton and try to pawn it off as proof of the Bible. Or consider the havoc my mother might wreak if her bones find their way into some science class to be compared with a typical male skeleton.
I chuckle at the thought, but I also check my skeletons twice. You can never be too careful. For example, there's a condition known as polydactyly--literally, "many digits"--in which people have extra fingers or toes. In one town in Spain, there has been so much inbreeding that almost everyone has six or seven fingers on each hand. I don't want any of my students unexpectedly claiming that a significant difference between chimps and us is the number of fingers or toes.
On the other hand, I wouldn't say no to a seven-fingered skeleton with 13 pairs of ribs. What a wonderful extra-credit assignment that would make, and what a wonderful example of how nature evades every generalization we try to impose on it. Take nothing for granted, I counsel my students: that is what makes a scientist. But don't ignore the exceptions, either. I'll make no bones about it: anatomic differences are what drive evolution-and its teaching.
Another broken board.
There's a really simple explanation: those bones are probably eight or ten thousand years old.
Thats because its not......
Most human females have a relatively wider pelvis than males because the human brain (even in a newborn) is too large to pass through a narrow birth canal. Thus, one of the reasons sexual dimorphism is so much more pronounced in humans than in most other primates is relative brain size. ("Don't trust me," I told her, "check it--the skeletons are there!") Bigger brains require bigger hips.They get the hips so well all can get the brains! Now THAT's science!
How old is it, then, and how did you reach that age?
Disagreements and clashes of opinion are rife among biologists, as they should be in a living and growing science. Antievolutionists mistake, or pretend to mistake, these disagreements as indications of dubiousness of the entire doctrine of evolution. Their favorite sport is stringing together quotations, carefully and sometimes expertly taken out of context, to show that nothing is really established or agreed upon among evolutionists. Some of my colleagues and myself have been amused and amazed to read ourselves quoted in a way showing that we are really antievolutionists under the skin.
How old is it, then, and how did you reach that age?
Diagnosis from a single image (and video)!
No, actually, you look at two other meat samples. One is 10,000 years old (as determined from...random BS pulled out of some dark place), the other is 70 million years old (aliens tell us). See, we somehow have knowledge of what 70 million year old flesh looks like, and that photo and the video show meat that looks totally different.
And you can't use carbon dating (or any similar technique) for it is a tool of teh Satan. We must rely then on the only other recourse: making stuff up.
Is it too late to join the dinosaur clan?
Got a good laff out of that one!
Very like.
Thanks for the ping!
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