Posted on 07/29/2011 9:24:53 AM PDT by SeekAndFind
A fossil touted since the time of Charles Darwin as the "missing link" between dinosaurs and birds is likely just a dinosaur, scientists have admitted in a new report in the journal Nature..
The proposal to reclassify the specimen Archaeopteryx, which has been presented since its discovery in 1861 as a key transitional link, highlights the shifting sands on which much of evolutionary theory is based, according to one expert in the field.
David Menton of Answers in Genesis has a Ph.D. in cell biology from Brown University, taught anatomy at Washington University School of Medicine, lectured in anatomy, was a consulting editor for "Stedman's Medical Dictionary" and has been profiled in "American Men and Women of Science – a Biographical Directory of Today's Leaders in Physical, Biological and Related Sciences."
He told WND the developments reported by Nature directly undercut the assumptions of Darwinian evolutionary theory.
"Just how many papers have we had talking about this being a bird?" he asked.
A summary of the scientific paper in naturenews explains that Xing Xu, a paleontologist at the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, is suggesting Archaeopteryx is "not a bird at all."
David Menton
The report says the latest discovery suggests the assumption that Archaeopteryx is "the evolutionary link between the two [birds and dinosaurs]" may need reconsideration.
The discovery, called Xiaotingia zhengi, was found in western Liaoning, China, in rocks dating to the Jurassic time frame, an assumed 161 million to 145 million years ago.
This one, like others, the report said, has feather impressions in the rock, but it also has claws on its forelimbs and sharp teeth.
"Xu reports that it also has extremely long middle and last finger bones and a wishbone with an L-shaped cross-section at one end.
(Excerpt) Read more at wnd.com ...
You really shouldn’t argue with a religious fanatic.
The crazy thing is there are mouth breathing half wits who actually believe automobiles have "creators" or "designers." After all, you see more evidence of transitionary fossils at your local junk yard than in any rock sample!
What rubes!
The fact is that it was the link between dinosaurs and birds. Then it was shown that this was not so.
The relationships are based on conjecture. Conjecture isn’t a scientific basis.
It would, in fact, ENFORCE that there was no genetic merging of the lines, if there were genetic problems with interbreeding.
So you are completely wrong about that and have, once again, no mechanism to explain what would stop a 2% genetic difference from accumulating, and apparently neither are you intelligent enough to understand that your proposed mechanism would in fact increase the likelihood of what I propose rather than making it impossible.
Would you like to try again?
What is going to stop a 2% genetic difference from accumulating over time in two separate populations of what once was the same species?
So your argument is that the small changes accumulate over time, a long time until the species “hops over the edge”, and becomes a new species?
By that logic, it would happen in one generation that two creatures would suddenly stop being able to breed with each other, and then diverge and become another species.
Now, here’s a question for you. Has this ever been observed? How does this square with the catastrophists who admit that evolution cannot be a slow mechanical process. Becaues there’s simply not enough time for these changes to result in what you would see.
So here’s my question, given a guaranteed mutation in one base pair, how long would it take to cross the gap between a man and a chimpanzee? That’s 150k base pairs.
You would be looking at 150k successive changes in one direction. Assuming equal drift between men and monkeys, and a population of men around 500 million people, that would mean 2 ^ 150000 / 8k (births a year).
That makes it a 1/8x10^18 power chance of it occurring over 2 million year. Assuming 5 billion instead of 500 million, gives us a 1/8x10^17 power chance of this occurring.
No. There is no edge. The edge is only in your mind. When walking from a forest into a swamp there is no “line” where forest becomes swamp.
Yes, it has been observed that two separate populations accumulate differences. It is an inevitable consequence of mutation and you haven’t yet come up with any mechanism that is going to prevent these differences from accumulating.
A 2% genetic difference between humans and chimps, and a 6-10% difference over the entire genome - would take some six million years.
The known mutation rate is more than sufficient to explain this change, because many changes are not “fixed” within either population.
So what is going to stop a 2% difference in genetic DNA from accumulating in two separate populations?
You still haven’t proposed a mechanism.
And your only mechanism to explain change in living systems is the one Darwin proposed. You owe a debt to Darwin because his explanation is the only one that you can agree to to account for changes within living systems.
So what is going to stop these changes from accumulating in two separate populations?
Yes, there is an edge. That’s the problem. The edge has never been observed.
By your logic assuming a fixed rate and pure randomness, we should not even expect to see the changes that we do see. That’s another problem. Not enough time has elapsed. So either the theory is wrong, or one of the other assumptions is wrong.
I’m not proposing a ‘different’ method. I’m simply arguing that there’s no evidence for this method actually occurring in nature. My personal belief is that species are immutable.
Didn’t I warn you about arguing with religious fanatics?
Check out “ring species” and then try to tell me with a straight face that the phenomena of increased genetic incompatibility with increased genetic difference has not been observed.
Assuming the observed rate of mutation we should see MORE changes than we see over six to seven million years of separate reproduction. Do you understand why we don’t see even MORE change?
Not enough time has elapsed? You don’t think that there has BEEN six or seven million years of separate reproduction? Well then, you reject almost the entirety of science - astronomy, geology, paleontology, physics, etc, etc. It seems your problem is not so much with Darwin, whose mechanism is the only explanation for change in biological systems you accept - but with almost all of the rest of science.
We see that no species is a perfect replicator. DNA polymerase itself has an inherent error rate. How can a species be “immutable” when mutations are the inevitable consequence of reproduction? What mechanism is keeping them “immutable” in the face of an inherent and inescapable mutation rate?
Finding the fossilized remains of homo sapiens in Jurassic strata would immediately falsify evolution.
That’s actually an argument from silence. Absence of evidence is not evidence of absence.
A scientific theory has to make a claim that can be tested. Fr’instance General Relativity made predictions about time dilation that could be tested and have been proven.
What predictions does Evolution make?
I’m more stunned by this:
“The discovery, called Xiaotingia zhengi, was found in western Liaoning, China, in rocks dating to the Jurassic time frame, an assumed 161 million to 145 million years ago.”
So are the creationists admitting that the earth is older than 6,000 years and scientific methods such as Carbon-14 dating are valid?
If Creationists can accept this, we have true evidence of evolution.
Yeah, I did. Seems that the understanding of ‘species’ is not clear in each of these cases.
“Assuming the observed rate of mutation we should see MORE changes than we see over six to seven million years of separate reproduction. Do you understand why we don’t see even MORE change?”
Actually, given the observed rate of mutation, we cannot explain how one species becomes another in the time period that exists. I just explained the numbers to you and why they don’t work.
“How can a species be “immutable” when mutations are the inevitable consequence of reproduction? What mechanism is keeping them “immutable” in the face of an inherent and inescapable mutation rate?”
The gulf is just too large to be beat through random mutations over time.
Your explanation of the numbers was ridiculous and showed only that you don't understand the subject. The observed mutation rate is more than enough to explain a 2% genetic difference over some six to seven million years given a 20 year generation time. That time period DOES exist. It is only a fantasy by those who wish to ignore all evidence that such a time frame doesn't exist.
What gulf? Some undefined “gulf” (of 2% genetic DNA difference) is going to keep species “immutable” when mutation is inevitable? That isn't a mechanism.
Once again I find myself in the position of explaining to you that using a word is not providing a mechanism.
Would you like to try again to describe a mechanism that is going to keep a species “immutable” in the face of INEVITABLE mutations?
It has been observed that the single loci nucleotide mutation rate per generation in humans is around 1 * 10^-6.
That means a 0.0001% change in DNA per generation.
Assuming a six million year separation and a 20 year generation time, a 1% change in DNA from that common ancestor accumulating in each branch such that they are some 2% different after six million years is more than accounted for.
Thus, to use the language of science....
The observed mutation rate in humans is both necessary and (more than) sufficient to explain a 2% genetic divergence between humans and chimpanzees over six million years.
You love to quote the 98% similarity between human and chimp.
how about supplying some proof, amd? Esp. since they claimed this well before the human DNA was completely mapped!
The entire genome (over 90% of which is not genetic DNA) isn't the issue - the genetic DNA is - so there is no discrepancy in one finding (the 98% similarity of genetic DNA) coming before we had the human genome sequenced.
As to evidence (science doesn't do “proof”) that our genes are 98% similar - there are any number of sources.
If you doubt their conclusions or analysis and are actually interested in the evidence - you can “BLAST” gene sequences on file and open to public access of any known human and chimp genes. You will find - as everyone else has - that human genetic DNA and chimp genetic DNA is around 98% exactly the same.
http://www.sciencedaily.com/releases/2006/10/061013104633.htm
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