Posted on 05/01/2006 8:29:14 AM PDT by SirLinksalot
Dinosaur Shocker
By Helen Fields
Neatly dressed in blue Capri pants and a sleeveless top, long hair flowing over her bare shoulders, Mary Schweitzer sits at a microscope in a dim lab, her face lit only by a glowing computer screen showing a network of thin, branching vessels. Thats right, blood vessels. From a dinosaur. Ho-ho-ho, I am excite-e-e-e-d, she chuckles. I am, like, really excited.
After 68 million years in the ground, a Tyrannosaurus rex found in Montana was dug up, its leg bone was broken in pieces, and fragments were dissolved in acid in Schweitzers laboratory at North Carolina State University in Raleigh. Cool beans, she says, looking at the image on the screen.
It was big news indeed last year when Schweitzer announced she had discovered blood vessels and structures that looked like whole cells inside that T. rex bonethe first observation of its kind. The finding amazed colleagues, who had never imagined that even a trace of still-soft dinosaur tissue could survive. After all, as any textbook will tell you, when an animal dies, soft tissues such as blood vessels, muscle and skin decay and disappear over time, while hard tissues like bone may gradually acquire minerals from the environment and become fossils. Schweitzer, one of the first scientists to use the tools of modern cell biology to study dinosaurs, has upended the conventional wisdom by showing that some rock-hard fossils tens of millions of years old may have remnants of soft tissues hidden away in their interiors. The reason it hasnt been discovered before is no right-thinking paleontologist would do what Mary did with her specimens. We dont go to all this effort to dig this stuff out of the ground to then destroy it in acid, says dinosaur paleontologist Thomas Holtz Jr., of the University of Maryland. Its great science. The observations could shed new light on how dinosaurs evolved and how their muscles and blood vessels worked. And the new findings might help settle a long-running debate about whether dinosaurs were warmblooded, coldbloodedor both.
Meanwhile, Schweitzers research has been hijacked by young earth creationists, who insist that dinosaur soft tissue couldnt possibly survive millions of years. They claim her discoveries support their belief, based on their interpretation of Genesis, that the earth is only a few thousand years old. Of course, its not unusual for a paleontologist to differ with creationists. But when creationists misrepresent Schweitzers data, she takes it personally: she describes herself as a complete and total Christian. On a shelf in her office is a plaque bearing an Old Testament verse: For I know the plans I have for you, declares the Lord, plans to prosper you and not to harm you, plans to give you hope and a future.
It may be that Schweitzers unorthodox approach to paleontology can be traced to her roundabout career path. Growing up in Helena, Montana, she went through a phase when, like many kids, she was fascinated by dinosaurs. In fact, at age 5 she announced she was going to be a paleontologist. But first she got a college degree in communicative disorders, married, had three children and briefly taught remedial biology to high schoolers. In 1989, a dozen years after she graduated from college, she sat in on a class at Montana State University taught by paleontologist Jack Horner, of the Museum of the Rockies, now an affiliate of the Smithsonian Institution. The lectures reignited her passion for dinosaurs. Soon after, she talked her way into a volunteer position in Horners lab and began to pursue a doctorate in paleontology.
She initially thought she would study how the microscopic structure of dinosaur bones differs depending on how much the animal weighs. But then came the incident with the red spots.
AdvertisementIn 1991, Schweitzer was trying to study thin slices of bones from a 65-million-year-old T. rex. She was having a hard time getting the slices to stick to a glass slide, so she sought help from a molecular biologist at the university. The biologist, Gayle Callis, happened to take the slides to a veterinary conference, where she set up the ancient samples for others to look at. One of the vets went up to Callis and said, Do you know you have red blood cells in that bone? Sure enough, under a microscope, it appeared that the bone was filled with red disks. Later, Schweitzer recalls, I looked at this and I looked at this and I thought, this cant be. Red blood cells dont preserve.
Schweitzer showed the slide to Horner. When she first found the red-blood-cell-looking structures, I said, Yep, thats what they look like, her mentor recalls. He thought it was possible they were red blood cells, but he gave her some advice: Now see if you can find some evidence to show that thats not what they are.
What she found instead was evidence of heme in the bonesadditional support for the idea that they were red blood cells. Heme is a part of hemoglobin, the protein that carries oxygen in the blood and gives red blood cells their color. It got me real curious as to exceptional preservation, she says. If particles of that one dinosaur were able to hang around for 65 million years, maybe the textbooks were wrong about fossilization.
Schweitzer tends to be self-deprecating, claiming to be hopeless at computers, lab work and talking to strangers. But colleagues admire her, saying shes determined and hard-working and has mastered a number of complex laboratory techniques that are beyond the skills of most paleontologists. And asking unusual questions took a lot of nerve. If you point her in a direction and say, dont go that way, shes the kind of person wholl say, Why?and she goes and tests it herself, says Gregory Erickson, a paleobiologist at Florida State University. Schweitzer takes risks, says Karen Chin, a University of Colorado paleontologist. It could be a big payoff or it could just be kind of a ho-hum research project.
In 2000, Bob Harmon, a field crew chief from the Museum of the Rockies, was eating his lunch in a remote Montana canyon when he looked up and saw a bone sticking out of a rock wall. That bone turned out to be part of what may be the best preserved T. rex in the world. Over the next three summers, workers chipped away at the dinosaur, gradually removing it from the cliff face. They called it B. rex in Harmons honor and nicknamed it Bob. In 2001, they encased a section of the dinosaur and the surrounding dirt in plaster to protect it. The package weighed more than 2,000 pounds, which turned out to be just above their helicopters capacity, so they split it in half. One of B. rexs leg bones was broken into two big pieces and several fragmentsjust what Schweitzer needed for her micro-scale explorations.
It turned out Bob had been misnamed. Its a girl and shes pregnant, Schweitzer recalls telling her lab technician when she looked at the fragments. On the hollow inside surface of the femur, Schweitzer had found scraps of bone that gave a surprising amount of information about the dinosaur that made them. Bones may seem as steady as stone, but theyre actually constantly in flux. Pregnant women use calcium from their bones to build the skeleton of a developing fetus. Before female birds start to lay eggs, they form a calcium-rich structure called medullary bone on the inside of their leg and other bones; they draw on it during the breeding season to make eggshells. Schweitzer had studied birds, so she knew about medullary bone, and thats what she figured she was seeing in that T. rex specimen.
Most paleontologists now agree that birds are the dinosaurs closest living relatives. In fact, they say that birds are dinosaurscolorful, incredibly diverse, cute little feathered dinosaurs. The theropod of the Jurassic forests lives on in the goldfinch visiting the backyard feeder, the toucans of the tropics and the ostriches loping across the African savanna.
To understand her dinosaur bone, Schweitzer turned to two of the most primitive living birds: ostriches and emus. In the summer of 2004, she asked several ostrich breeders for female bones. A farmer called, months later. Yall still need that lady ostrich? The dead bird had been in the farmers backhoe bucket for several days in the North Carolina heat. Schweitzer and two colleagues collected a leg from the fragrant carcass and drove it back to Raleigh.
AdvertisementAs far as anyone can tell, Schweitzer was right: Bob the dinosaur really did have a store of medullary bone when she died. A paper published in Science last June presents microscope pictures of medullary bone from ostrich and emu side by side with dinosaur bone, showing near-identical features.
In the course of testing a B. rex bone fragment further, Schweitzer asked her lab technician, Jennifer Wittmeyer, to put it in weak acid, which slowly dissolves bone, including fossilized bonebut not soft tissues. One Friday night in January 2004, Wittmeyer was in the lab as usual. She took out a fossil chip that had been in the acid for three days and put it under the microscope to take a picture. [The chip] was curved so much, I couldnt get it in focus, Wittmeyer recalls. She used forceps to flatten it. My forceps kind of sunk into it, made a little indentation and it curled back up. I was like, stop it! Finally, through her irritation, she realized what she had: a fragment of dinosaur soft tissue left behind when the mineral bone around it had dissolved. Suddenly Schweitzer and Wittmeyer were dealing with something no one else had ever seen. For a couple of weeks, Wittmeyer said, it was like Christmas every day.
In the lab, Wittmeyer now takes out a dish with six compartments, each holding a little brown dab of tissue in clear liquid, and puts it under the microscope lens. Inside each specimen is a fine network of almost-clear branching vesselsthe tissue of a female Tyrannosaurus rex that strode through the forests 68 million years ago, preparing to lay eggs. Close up, the blood vessels from that T. rex and her ostrich cousins look remarkably alike. Inside the dinosaur vessels are things Schweitzer diplomatically calls round microstructures in the journal article, out of an abundance of scientific caution, but they are red and round, and she and other scientists suspect that they are red blood cells.
Of course, what everyone wants to know is whether DNA might be lurking in that tissue. Wittmeyer, from much experience with the press since the discovery, calls this the awful questionwhether Schweitzers work is paving the road to a real-life version of science fictions Jurassic Park, where dinosaurs were regenerated from DNA preserved in amber. But DNA, which carries the genetic script for an animal, is a very fragile molecule. Its also ridiculously hard to study because it is so easily contaminated with modern biological material, such as microbes or skin cells, while buried or after being dug up. Instead, Schweitzer has been testing her dinosaur tissue samples for proteins, which are a bit hardier and more readily distinguished from contaminants. Specifically, shes been looking for collagen, elastin and hemoglobin. Collagen makes up much of the bone scaffolding, elastin is wrapped around blood vessels and hemoglobin carries oxygen inside red blood cells.
Because the chemical makeup of proteins changes through evolution, scientists can study protein sequences to learn more about how dinosaurs evolved. And because proteins do all the work in the body, studying them could someday help scientists understand dinosaur physiologyhow their muscles and blood vessels worked, for example.
Proteins are much too tiny to pick out with a microscope. To look for them, Schweitzer uses antibodies, immune system molecules that recognize and bind to specific sections of proteins. Schweitzer and Wittmeyer have been using antibodies to chicken collagen, cow elastin and ostrich hemoglobin to search for similar molecules in the dinosaur tissue. At an October 2005 paleontology conference, Schweitzer presented preliminary evidence that she has detected real dinosaur proteins in her specimens.
Further discoveries in the past year have shown that the discovery of soft tissue in B. rex wasnt just a fluke. Schweitzer and Wittmeyer have now found probable blood vessels, bone-building cells and connective tissue in another T. rex, in a theropod from Argentina and in a 300,000-year-old woolly mammoth fossil. Schweitzers work is showing us we really dont understand decay, Holtz says. Theres a lot of really basic stuff in nature that people just make assumptions about.
young-earth creationists also see Schweitzers work as revolutionary, but in an entirely different way. They first seized upon Schweitzers work after she wrote an article for the popular science magazine Earth in 1997 about possible red blood cells in her dinosaur specimens. Creation magazine claimed that Schweitzers research was powerful testimony against the whole idea of dinosaurs living millions of years ago. It speaks volumes for the Bibles account of a recent creation.
This drives Schweitzer crazy. Geologists have established that the Hell Creek Formation, where B. rex was found, is 68 million years old, and so are the bones buried in it. Shes horrified that some Christians accuse her of hiding the true meaning of her data. They treat you really bad, she says. They twist your words and they manipulate your data. For her, science and religion represent two different ways of looking at the world; invoking the hand of God to explain natural phenomena breaks the rules of science. After all, she says, what God asks is faith, not evidence. If you have all this evidence and proof positive that God exists, you dont need faith. I think he kind of designed it so that wed never be able to prove his existence. And I think thats really cool.
By definition, there is a lot that scientists dont know, because the whole point of science is to explore the unknown. By being clear that scientists havent explained everything, Schweitzer leaves room for other explanations. I think that were always wise to leave certain doors open, she says.
But schweitzers interest in the long-term preservation of molecules and cells does have an otherworldly dimension: shes collaborating with NASA scientists on the search for evidence of possible past life on Mars, Saturns moon Titan, and other heavenly bodies. (Scientists announced this spring, for instance, that Saturns tiny moon Enceladus appears to have liquid water, a probable precondition for life.)
Astrobiology is one of the wackier branches of biology, dealing in life that might or might not exist and might or might not take any recognizable form. For almost everybody who works on NASA stuff, they are just in hog heaven, working on astrobiology questions, Schweitzer says. Her NASA research involves using antibodies to probe for signs of life in unexpected places. For me, its the means to an end. I really want to know about my dinosaurs.
AdvertisementTo that purpose, Schweitzer, with Wittmeyer, spends hours in front of microscopes in dark rooms. To a fourth-generation Montanan, even the relatively laid-back Raleigh area is a big city. She reminisces wistfully about scouting for field sites on horseback in Montana. Paleontology by microscope is not that fun, she says. Id much rather be out tromping around.
My eyeballs are just absolutely fried, Schweitzer says after hours of gazing through the microscopes eyepieces at glowing vessels and blobs. You could call it the price she pays for not being typical.
I tried that in my calc class regarding differential equations, but it didn't fly.
That, by your defintion would be impossible, and so inevitably such a skeleton would simply be defined either as non-modern, or not found in one million year-old strata. Such as: or or
Make no mistake about it,... They are like modern human footprints. If one were left in the sand of a California beach today, and a four-year old were asked what it was, he would instantly say that somebody had walked there. He wouldn't be able to tell it from a hundred other prints on the beach, nor would you.
Tim White
The distinctinve spores of a flowering plant in two-million year old strata.
What? I think even evolutionary theory posits flowering plants in existence long before 2 millions years ago.
Cordially,
Hey, skull-man...perhaps you shouldn't read this link and the ones that follow. It seems that your skulls aren't sequential at all, nor are they accurately categorized.
http://emporium.turnpike.net/C/cs/emcon.htm
Nice pictures! What are they? What is the context?
I have examined your link:
http://emporium.turnpike.net/C/cs/emcon.htm
All I see is opinion based on religious belief. The opening line is "When the fossil evidence is viewed from a creationist's point of view..." It goes downhill from there.
For example, point #1 of a list of five is "Modern humans have existed for 4.5 million years, which is before the australopithecines existed by the evolutionists time scale." This is given with no supporting data whatsoever. The closest thing to support is the line,
At the bottom of Bed I in the Olduvai gorge is a circular stone structure 14 ft. in diameter made by humans, similar to those in use today by the Okombambi tribe of Southwest Africa. That means true humans were around 2 million years ago by the evolutionist's time scale, before Homo erectus and the Australopithecines (Lubenow, 1992, 172-173).
This is not convincing: the claim of modern humans at 4.5 million years is not supported by claiming they were there 2.0 million years ago. And that claim is based not on fossil evidence, but on "a circular stone structure 14 ft. in diameter" attributed to humans, but not documented as such.
Your claims, and those of this website, are not standing up to the least bit of scientific scrutiny.
Admit it, you have come to the conclusions you are posting based on your religious belief, not on scientific evidence. You (and the creation sites) are trying to twist the evidence to fit your beliefs. I call this "Pretzel Science."
So far, your scientific credibility is approaching zero. Care to try again?
ps. Do you ever read any of the actual science websites, or is your entire education in this field based on creationist sites?
That was my point too. I don't know if you read my reply. I also still believe it's choices that have consequences. People use all kinds of ideas, be it religion, or Darwinism, or who knows what else, to justify a choice. If the choice is motivated from hate, it's probably not going to have lovely consequences.
Hi!
Remember, a lot of these people come from nonscientific backgrounds where fraud is much more common.
Ahhh, that is a problem. I suppose he would have to requisition it back from whatever lab he kindly donated it to for study.
I don't dispute Pinker and Wilson are highly erudite men, and I don't recall saying I thought they were fools. I just don't think either of them has worked through the implications of their "philosophical naturalism," and it is plain to me that both men are constructing systems that are designed from the get-go to obviate the necessity of God. I do not think that good science can start from a categorical bias like this. Especially in light of the fact that God is not an "object" for science at all. FWIW.
I'm glad you're still talking to me though RWP. You know, we can always just cordially agree to disagree.... Obviously, we do not look at the world in the same way; but this is hardly a rare occurrence these days. Just possibly we might learn something from each other.
Once there were only two fossils standing between eohippus and horse, now there are about twenty, occuring in a graded sequence, inside a graded geological sequence, predicted, and then found, and creationists are now happy to claim that every single pair of them have a "fossil gap" between them. The argument doesn't rest on continuous evidence, it rests on inductive reasoning about the fossils that we do see, to explain why they have so much in common, along what looks like a graded continuous spectrum of forms, chemistry, morphology and function. Do you reject the law of universal gravitation because there are large gaps between stars for which no evidence exists. Why are you so concerned about fossil gaps, when the deceitful, left-wing, athiestic stellar gaps are so much larger?
I accept your challenge, King Prout! And look forward to your rebuttal. Unfortunately, I'm having a busy day today, and will not have the time to write until this evening. Thank you for your patience!
At the bottom of the geological column in the so called Cambrian rocks are found highly complex creatures: trilobites, worms, sponges, jellyfish, etc., all without ancestors. It's as though you "turned the light on" in the fossil record. These are highly complex life forms appearing on the scene without forerunners.
The Cambrian explosion has been found to not be as explosive as thought. Many organisms found there did have precursors, but these were not discovered earlier because they were small and soft-bodied and thus not easily fossilized. A mass extinction event at this time allowed rapid radiation into multiple organisms. Due to the short duration of the radiation many early organisms would not be preserved.
Insects - When found in the fossil record, they are already developed without ancestors.
The fossil record for the origin of insects is very poor because insects are small and their exoskeletons easily biodegrade. They evolved in the Devonian. The earliest insects we have are primitive wingless hexapods related to springtails, bristeltails, the tiny diplurans, and others. Wings evolved rapidly in the Carboniferous, and their origin is uncertain.
Invertebrates and vertebrates - Transitional forms leading to vertebrates are absent even though the transition supposedly took millions of years. It is theorized that life passed through a stage where a creature possessed a simple rod-like notochord. This has not been found.
This will come as quite a surprise to the invertebrate chordates.
Fish to Amphibian - Fin to feet... Evolutionist glibly cite a Fish --> Amphibian --> Reptile --> Mammal progression in their theory, however there is a large gap in the fossil record between fish and amphibians.
This gap is rapidly being closed, only a few weeks ago a fossil fish with jointed forelimbs was reported, this is a transitional species to the evolution of tetrapods.
Mammals just appear in the fossil record, again without transitional forms
This is disgusting. Mammals evolved from Permian cynodonts through a series of protomammals.
The primates - lemurs, monkeys, apes and man appear fully formed in the fossil record.
Not true.
And finally, dinosaurs. Again there is the absence of transitional series leading to these giants.
Again not true. Dinosaurs evolved from archosaurs. Two transitional species with intermediate traits are Herrerasaurus and Eoraptor.
The most often cited "example" of a transitional form is the Archaeopteryx which has been touted as a reptile to bird transition. However, this creature is controversial and enveloped in dispute.
I suppose you could say it is "controversial and enveloped in dispute" just because creationists don't like it. Among scientists it is agreed to be an actual organism transitional between reptiles and birds. The only debate there is whether birds evolved from theropod dinosaurs or if they split off before theropod dinosaurs diverged. All agree it is a transitional form.
Well, aren't you glad he told you!
The process by which many scientists, IMO, come to philosophical/metaphysical naturalism is by observing the success of methodological naturalism. If you don't seek supernatural explanations in your scientific work, and you see the success of that approach, you have to at least consider why you need to draw a line between scientific work and everything else. Most of us didn't set out to eliminate deities. We just noticed they never appear. I doubt Pinker or Wilson set out to construct an atheistic system; they're just used to eliminating unnecessary entities from their model.
Well, aren't you glad he told you!
And here I could have saved six years of grad school! All those hours in the bone lab, wasted. Sigh!
Perhaps we should bestow upon him an honorary doctorate. They're quite the rage in some circles.
(When I tickled her, she would say, "Stop it, some more!"..)
That's cute!
You corrected me: What? I think even evolutionary theory posits flowering plants in existence long before 2 millions years ago.
Thanks for the correction. I meant to say two hundred million years.
I can't find the exact source of the tracks.
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