googlef87758e9b6df9bec.html A Sure Word: Evolution’s Discordant Dates

Sunday, June 22, 2008

Evolution’s Discordant Dates

One argument I constantly hear in support of evolution is the seeming harmony of different sciences that support evolution: biology, geology, astronomy, physics, chemistry, etc, all marvelously work together to paint a seamless story of the unfolding of life and the universe. Is there such a concordance of data? To evolutionists there certainly is. But I think the fact of the matter is that most of the seeming concordance is the result of evolutionists forcing the facts to comply.

A good example of this was discussed lately in an AP article titled, Aussie dinosaur bone defies theories. From the article:
A dinosaur bone discovered in Australia has defied prevailing wisdom about how the world's continents separated from a super-continent millions of years ago, a new study says.

The 19-centimetre bone was found in southeastern Australia but it comes from a very close cousin to Megaraptor, a flesh-ripping monster that lorded over swathes of South American some 90 million years ago.
OK, that’s easy to understand. A fossil is found in Australia of a dinosaur related to dinos that lived in South America. Both supposedly lived 90 million years ago. The article continues:
Gondwana broke up during the Cretaceous period to form South America, Africa, Antarctica and Australia.

The standard theory is that the first continents to go were South America and Africa, which pulled away from Gondwana around 120 million years ago.
Oh. I see the problem. These dinosaurs lived on different continents 90 millions ago yet the continents separated 120 million years ago. That is a pickle. But couldn't they have been together once and were simply separated for 30 million years after the continents divided? The scientists have already ruled that out:
The investigators, led by Nathan Smith of the University of Chicago, say the two dinosaurs are so similar the two land masses of South America and Australia could not have been separated for so many millions of years beforehand.

If that had been the case, evolutionary pressures would have pushed the dinos in different directions as they adapted to their changing environments.
Wow, that certainly could put a kink in the theory, huh? On the one hand, these dinosaurs could not have been separated for 30 millions years but on the other hand, how did this dinosaur get from South America to Australia so long after the continents had been separated? This evidence is certainly discordant. Either the date when the dinosaurs lived is wrong or the date when the continents were separated is wrong. Which theory would get tweaked?Actually, neither. The scientists simply came up with a new theory to explain both:
They speculate that land bridges must have persisted between southern South America and the Western Antarctic Archipelago "until at least the Late Eocene," a period that began some 40 million years ago.
How convenient. Unwilling to compromise on the “strong concordance” of dates, scientists simply invent a land bridge to explain it. The dates remain firmly established and the Theory of Evolution marches on.


3 comments:

NP said...

The only conventional wisdom challenged here was the theory that Megaraptor was endemic to South America. It's going to take a lot more than a single ulna to falsify currently accepted paleogeology that is based on far more rigorous lines of evidence.

It's not inconceivable that fauna can translocate from one continent to another. It's been the case with early primates, and even today you can look to places like the Galapagos Islands that are several miles away from the mainland.

But feel free to twist this story any way you like.

RKBentley said...

NP,

You know, I appreciate you visiting my blog and I appreciate your comments. However, you’re a little out of line when you accuse me of “twisting” the story. Did you happen to read the story? The title alone says it all: “Aussie dinosaur bone defies theories.”

The discordant dates dilemma is not my spin on the article – it is the subject of the article! The first 9 paragraphs are devoted to explaining the precise quandary surrounding this find. In the final paragraph, the entire thing is dismissed with little more than hand waving.

You said, “It's going to take a lot more than a single ulna to falsify currently accepted paleogeology that is based on far more rigorous lines of evidence.” This bone is sort of like that hypothetical rabbit in the Pre-Cambrian. It’s only a single find, but it defies the entire theory. You have the same attitude as the writers of this article – you dismiss it. But your attitude is typical and I’m used to it by now. I think other readers can see it for what it is.

God Bless!!

RKBentley

NP said...

I have re-read the article, and I apologize for saying you twisted it. I still don't think you've given a fair representation of the significance of this new finding, but I now see that you are merely being the messenger here.

Let me first up just point out that popular press articles on science can often contain factual errors and tend to lean towards sensationalism. Maybe the scientists overstated their case when speaking to the reporter - after all there is no peer review in this setting. Or maybe the reporter misunderstood his point. There are no direct quotes of Nathan Smith in the article you cited.

I looked up another article where he does have a direct quote, and this is what he says:
"It doesn't rewrite the biogeographic history of the early Cretaceous in Australia, but it adds an important well-constrained data point".
http://www.thetechherald.com/article.php/200824/1219/Arm-bone-links-Australian-dinosaur-to-ancient-supercontinent

If you read this other article, you'll find it is more well-balanced. The significance of this finding is still controversial, so for you to claim that there are discordant dates or that handwaving is going on is rather premature.

Let's be clear; a pre-Cambrian rabbit would be utterly earth-shattering, or rather, geological column shattering. Given our current understanding of evolution, such a finding - if shown to be legitimate - would be extremely difficult for paleontologists to account for, because there is simply no conceivable way in which a mammalian tetrapod could have existed at the time.

On the other hand, as I pointed out in my previous comment, this ulna - if it is indeed from the same megaraptor genus as the one found in South America, would not be entirely inconceivable even given our current models of paleogeography. We know that fauna can cross bodies of water.

But even so, assuming that scientists are forced to revise their understanding of the locations of the continents during the Cretaceous - so what? How does this lend any support to your position of young earth creationism?