Posted on 04/15/2005 6:39:50 AM PDT by doc30
Reproductive Riddle Unscrambled
A pair of fossilized eggs found inside pelvis of dinosaur supports a link with birds
Friday, April 15, 2005 Updated at 8:30 AM EST From Friday's Globe and Mail
Calgary — Scientists have for the first time discovered fossilized eggs inside the body of a dinosaur, which provides concrete clues about ancient reproduction and supports the theory that birds evolved from dinosaurs, according to research published today. The pair of hard-shelled eggs about the size of large, long yams were found inside the pelvis of a female oviraptorid, a meat-eating bipedal dinosaur that lived about 80 million years ago.
I was completely stunned," said the University of Calgary's Darla Zelenitsky, an expert in dinosaur reproductive biology, who was brought in to study the specimen found three years ago in China's southern Jiangxi province.
Never before have complete eggs been discovered inside a fossilized dinosaur, but there has been much speculation about whether dinosaurs laid numerous eggs at once like crocodiles or produced one egg at a time like birds.
A report published in today's issue of the journal Science finally puts an end to that debate.
"There's always been two camps among paleontologists: those that believe birds came from dinosaurs and those that believe birds came from other reptiles," Dr. Zelenitsky, the report's co-author, said. "But this provides further evidence that birds are from dinosaurs."
While crocodiles can lay 20 to 60 eggs at a time, it takes a modern-day chicken 25 to 30 hours to produce and lay one egg. That's because both oviducts, or Fallopian tubes, in reptiles produce many eggs at once, but in birds, only one oviduct is operating to produce one egg at a time.
"This specimen showed that these dinosaurs were more like birds in that they were laying one egg at a time," Dr. Zelenitsky said. ". . . but in this dinosaur, both the oviducts were functional like in crocodiles, but each oviduct was only producing one egg."
Previous discoveries of dinosaur nests of eggs or clutches have appeared as though the creatures laid their eggs in pairs but, until now, scientists had no proof that was the case. In fact, many denied the possibility that eggs were laid in pairs.
Renowned dinosaur hunter Philip Currie of the Royal Tyrrell Museum in Drumheller, Alta., pointed out that the only resolution to that dispute was the remote chance of discovering eggs inside a body cavity.
Uncovering this oviraptorid specimen, he said, is essentially like finding the "smoking gun."
Report co-author Tamaki Sato of the Canadian Museum of Nature in Ottawa said scientists finally have some answers about how dinosaurs laid eggs.
"This supports the bird-dinosaur relationship," she added.
The eggs studied are 18 centimetres long and six centimetres in diameter and are covered with ridges and bumps. While protected by a hard shell like bird eggs, rather than a leathery one as in reptiles, these eggs are neither bird-like nor crocodile-like in appearance.
Oviraptorids were toothless, short-beaked creatures that weighed about 40 kilograms and were about two metres long. They were also initially thought to be the egg-stealers of the Upper Cretaceous period.
No replies. Outstanding.
"Such as?"
Cystic Fibrosis, and almost all genetic disease. Our ancient ancestor knew non of it, because it only appeared later. That's why the Europeans have a MUCH higher risk for CF than Mesoamericans or Africans or Orientals.
Strider4, you're missing a very important point. When they only have a fossil, Darwinistas are allowed to conjecture/fabricate any set of soft tissues around the skeleton that enables them to draw pretty pictures to put in children's textbooks, as facts, to get little Johnny believing that evolution is patently obvious.
Oh, and then they're allowed to rail against 'creationists' for dishonesty when they cite any quotes that are the slightest bit out of context, and all without the slightest hint of irony.
Hey Ichy
Here's a guy that signs up today and heads right for a Crevo thread spouting the usual gibberish. He ain't worth it.
Troll City
Sugar Gliders are in fact baby Greater Gliders.
People buy them, like baby alligators, thinking they're cute, and before long they've got this ravening monster on their hands.
The time to worry is when they get into the air ducts, Then you need to call Ellen Ripley.
Nice ad hominem. Any other mindless insults you want to throw?
Why don't you call him a mouth breathing Neanderthal while you're at it too. jbloedow has been very patient with all of you Darwinists, you have no excuse for your behavior towards him.
You have put your foot in it, big time.
The dictionary says a bird is "a feathered animal with two wings and two feet". Archaeopteryx is therefore just a bird and evolution never happened.
Here endeth the Creationist lesson on Archaeopteryx.
As I see it, the technique is that of ALS and his troop of tiny-brained, vicious troglodytes. That is, a particularly stupid, childish, and interminable nay-saying and innuendo with the avowed purpose of getting the thread pulled.
"NUKE the unborn gay whales!"
Gotta nuke sumthin'
--Nelson Muntz
"You have put your foot in it, big time."
?
"The dictionary says a bird is "a feathered animal with two wings and two feet". Archaeopteryx is therefore just a bird and evolution never happened."
I don't know what point you're trying to make. Archy had no more in commmon with dinosaurs than the mosquito in Jurassic Park. It was an eons old bird species that doesn't exist anymore. I don't get what you're trying to say.
Post to your self addiction!
Successful predictions always serve as evidence. Which is what I said. What I was also saying was the postulate that flying squirrels might evolve into genuine flyers is not a successful prediction, but just a prediction.
And I was generalizing from that specific example, because there are many other predictions in the evo literature where untested hypotheses seem to stand as evidence.
As a sort-of example, ichtheoman or whatever posted a big long "summary" of the supposed evolution of birds from dinos. One line from that was:
1. Scales modified into downy feathers for heat retention.
I'm going out on a bit of a limb here, because I haven't investigated this particularly claim exhaustively, but unless you have demonstrated that there was selective pressure of some sort that resulted in the increased heat retention from the downy feathers being advantageous to the first feather owner, then you have proved nothing. Obviously these creatures were in an environment where scales were adaptively beneficial to start with.
For natural selection to work, you not only need mutation/change, but you also need selective pressures that favour that adaption. You have to prove (well, provide evidence for) the selective pressure that favoured the adaption as well as the adaption.
For example, if there was a heat wave, or this locale was tropical, or there were lots of predators with nasty teeth that liked soft feathers over scales, then these nice heat-retentive feathers would not be beneficial, so simply saying you can imagine why these would be beneficial does not make it so. Without the evidence that it was, it is just conjecture.
Here's the issue: God says that death (both spiritual and physical) is the condemnation that results from Adam's sin. If you say that death preceeds sin, then you deny the purpose of Calvary (and a host of other tennants of faith.)
The key verse for you is this:
And I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel
Remember what I said earlier? "Yea, hath God said...?"
You can google all you want. I'll stick to the established texts on the subject. And that last post again shows you do not know what you are talking about. your analogy with a car is pointless. If you want to talk about entropy, go here:
http://www.entropysite.com/students_approach.html
http://www.nap.edu/html/oneuniverse/energy_knowledge_concept_3.html
http://itl.chem.ufl.edu/4411/2041/lec_u.html
Make sure you learn the role of entropy, enthalpy and free energy before posting again: delta G = delta H minus T * delta S
and how this fits with spontaneous changes in a chemical system.
*shrug* Life is too short for all this whining. Get real!
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