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Posted on 08/13/2003 9:02:05 PM PDT by nwrep
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2 hours, 55 minutes ago
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By RAMOLA TALWAR BADAM, Associated Press Writer
BOMBAY, India - U.S. and Indian scientists said Wednesday they have discovered a new carnivorous dinosaur species in India after finding bones in the western part of the country.
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The new dinosaur species was named Rajasaurus narmadensis, or "Regal reptile from the Narmada," after the Narmada River region where the bones were found.
The dinosaurs were between 25-30 feet long, had a horn above their skulls, were relatively heavy and walked on two legs, scientists said. They preyed on long-necked herbivorous dinosaurs on the Indian subcontinent during the Cretaceous Period at the end of the dinosaur age, 65 million years ago.
"It's fabulous to be able to see this dinosaur which lived as the age of dinosaurs came to a close," said Paul Sereno, a paleontologist at the University of Chicago. "It was a significant predator that was related to species on continental Africa, Madagascar and South America."
Working with Indian scientists, Sereno and paleontologist Jeff Wilson of the University of Michigan reconstructed the dinosaur skull in a project funded partly by the National Geographic (news - web sites) Society.
A model of the assembled skull was presented Wednesday by the American scientists to their counterparts from Punjab University in northern India and the Geological Survey of India during a Bombay news conference.
Scientists said they hope the discovery will help explain the extinction of the dinosaurs and the shifting of the continents — how India separated from Africa, Madagascar, Australia and Antarctica and collided with Asia.
The dinosaur bones were discovered during the past 18 years by Indian scientists Suresh Srivastava of the Geological Survey of India and Ashok Sahni, a paleontologist at Punjab University.
When the bones were examined, "we realized we had a partial skeleton of an undiscovered species," Sereno said.
The scientists said they believe the Rajasaurus roamed the Southern Hemisphere land masses of present-day Madagascar, Africa and South America.
"People don't realize dinosaurs are the only large-bodied animal that lived, evolved and died at a time when all continents were united," Sereno said.
The cause of the dinosaurs' extinction is still debated by scientists. The Rajasaurus discovery may provide crucial clues, Sereno said.
India has seen quite a few paleontological discoveries recently.
In 1997, villagers discovered about 300 fossilized dinosaur eggs in Pisdura, 440 miles northeast of Bombay, that Indian scientists said were laid by four-legged, long-necked vegetarian creatures.
Indian scientists said the dinosaur embryos in the eggs may have suffocated during volcanic eruptions.
Everytime als has outed the evos they whine and get the thread pulled because they are embarassed and then like you the guilty ... blame the innocent !
Actually he was banned because he was unable to interact in a civil manner. He couldn't even get along with the other creationists. He got himself banned. If an evo behaved that way they would've been banned much sooner.
He said he was here to disrupt the threads and now that he's gone, suddenly there's civilized debate again. Whoda thunk it!
That reminds me of a line from Linda Ellerbee's book about her journalism days. As an employee at the Associated Press long ago, she had written an email intended for a friend, in which she had dished gossip about her bosses, then accidentally broadcast it out on the entire AP wire...
In her book she wrote (from my memory, may not be verbatim), "they fired me, but only because their lawyers informed them that they could not have me killed."
Welcome to the club. :-)
Name more than the one ... ex- creationist !
After discovering this same data on another thread along with more discussion than has appeared here (I've taken the liberty of pinging the participants of that discussion), I see what the "mystery" is supposed to be -- it's supposed be why did some sites have multiple mutations while (small) stretches of other sites had none? In other words, why do the mutations appear clustered?
(You know, it would really help if people explained their points and questions in more detail, instead of leaving people to guess what the poster was thinking...)
[LLLICHY wrote:] "U238" that decays thrice, pretty good trick when there is "U238" that does not decay at all in 50,000,000 years.
Actually, no site had mutations "thrice". Three different bases at a given site is only *two* mutations (one original base, plus two mutations from it to something else).
Here's the "mutation map" from the actual DNA data:
--1-12--1-1-1-1--------1112112--1---1-11-1--------1 ALL/nNo mutations ("-") in about half the sites, one mutation at several (17) sites, two mutations at three sites.
The first thing to keep in mind that random processes tend to "cluster" more than people expect anyway. People expect "randomness" to "spread out" somewhat evenly, but instead it's usually more "clumped", for statistical reasons that would be a diversion to go into right now. So "that looks uneven" isn't always a good indication that something truly is non-random.
If you don't believe me on that, I wrote a program which made 23 mutations totally at random on a 51-site sequence, then repeated the process to see what different random outcomes would look like:
10 X$=STRING$(51,"-") 20 FOR I=1 TO 23 30 J%=INT(RND*51)+1 40 C$=MID$(X$,J%,1) 50 IF C$="-" THEN MID$(X$,J%,1)="1" ELSE MID$(X$,J%,1)=CHR$(ASC(C$)+1) 60 NEXT I 70 PRINT X$ 80 GOTO 10Yeah, it's BASIC, so sue me. Here's a typical screenful of the results:
-21---1---2---111----2-----2-1121-------1---1--11-1 -1--1--21-11---1-1--1-1---1----1---21-11111---11--- 3-11---3-----1-----11-2-1---1--1----3--2---1--1---- ---1-1--22--1-1--2-2111--1-1111---1------1-------1- ---32----1-11-1-----1---2-231----1------1-----11--1 ----2---21--1---4----1-------------11-1--111-11-211 11--1-1---1-----1--1------1----3111--1----111-2-1-2 1112---1-3-1----1-1-----1-1------121--111-------1-1 -111121--1----1----1-1-1-1-11-2---1-1-------1-111-- -----------11-1---11-11--------21----12211--1---131 --1-211-1-1----21--11-1-2----1--1----11---11-----11 12---1-13------------2---21-21---11-1-1-1--2------- -----2-1---1-1----21--11-11-1---111-1--111-----2--1 -----1-----1-1-1-1---1-2----11-21-11--1-111---1-21- ---11--1-1-122-1-1-1--1-----2-1-1-1-------1-1---111 --2--11----2--1---12-2----1-1---1-1--1--12----1-1-1 -111-1-----1-1----------1-21111--1-2-11-11-1----11- 11-1--211-1221-----1--1-----11--1-2-1----------11-- -----1-12-11---2-1---11--1-2--1----11---111-1----11 11----1--12---12----1---31---1-11----2--1-11-1----- ---1--111-1--1-1-111----1-21----1-1-3---1------2--1 -2-11----1-1------1------2-1-1--111-111-1-1----1111 1--1--1-1---1-111111--2--1-1------112----2---11----Notice how oddly "clustered" most of them look, including one run which left a 13-site stretch "absolutely untouched", contrary to intuition (while having *4* mutations at a single site!)
Frankly, I don't see anything in the real-life DNA mutation map which looks any different from these truly random runs. Random events tend to cluster more than people expect. That solves the "mystery" right there.
Also, there may be a selection factor -- the GLO gene is a *lot* bigger than this. One has to wonder if this small 51-bp section was presented just because it was the one that looked "least random". That would be a no-no, since one can always hand-select the most deviant subset out of larger sample in order to artificially skew the picture.
However, since there are some interesting evolutionary observations to be made, let's look at that DNA data again, slightly rearranged:
TAC CCC GTG GAG GTG CGC TTC ACT CGG GCG GAC GAC ATC CTG CTG AGC CCC PIG TAC CCC GTG GAG GTA CGC TTC ACT CGC GGG GAC GAC ATC CTG CTG AGC CCC BOS TAC CCC GTA GAG GTG CGC TTC ACC CGA GGC GAT GAC ATT CTG CTG AGC CCC RAT TAC CCC GTG GAG GTG CGC TTC ACC CGA GGT GAT GAC ATC CTG CTG AGC CCG MOUSE TAC CCT GTG GGG GTG CGC TTC ACC CGG GGG GAC GAC ATC CTG CTG AGC CCC GUIN PIG TAC CTG GTG GGG GTA CGC TTC ACC TGG AG* GAT GAC ATC CTA CTG AGC CCC HUMAN TAC CTG GTG GGG CTA CGC TTC ACC TGG AG* GAT GAC ATC CTA CTG AGC CCC CHIMPANZEE TAC CCG GTG GGG GTG CGC TTC ACC CAG AG* GAT GAC GTC CTA CTG AGC CCC ORANGUTAN TAA CCG GTG GGG GTG CGC TTC ACC CAA GG* GAT GAC ATC ATA CTG AGC CCC MACAQUEHere I've put spaces between codons, and clustered the closely-related species together: pig/cow as ungulates, rat/mouse for their obvious relationship, guinea pig right below them but separated because of the pseudogene nature of its GLO gene, then primates all in a group, with man's closest relative, the chimp, immediately below him, followed by the more distant orangutan, and the even more distant macaque. Also note that the top four have "working" GLO genes, and the bottom five have "broken" GLO pseudogenes.
First, let's consider just the four species with working GLO genes. Evolution predicts that even over large periods of time, these genes will be "highly conserved", with natural selection weeding out mutations that could "break" the gene. Note that the mutations will still have occurred in individuals of the population, but natural selection will "discourage" that mutation from spreading into the general population.
And before we go any further, let's talk about the "universal genetic code". In all mammals (indeed, in almost all living organisms), each triplet of DNA sites cause a particular amino acid to be formed. The mapping of triplets (called "codons") to amino acids is as follows:
| Second Position of Codon | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| F i r s t P o s i t i o n |
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(The above table imported from http://psyche.uthct.edu/shaun/SBlack/geneticd.html, which also has a nice introduction to the genetic code.)
Another version of the same table with nifty Java features and DNA database lookups can be found here.
The thing which is most relevant to the following discussion is the fact that most of the genetic codes are "redundant" -- more than one codon (triplet) encodes to exactly the same amino acid. This means that even in genes which are required for the organism, certain basepair mutations make absolutely no difference if the change is from one codon which maps into amino acid X to another codon which still maps into amino acid X. (This fact allows certain kinds of evolutionary "tracers" to be "read" from the DNA, as described here).
Now back to our DNA data. The redundancy in the genetic code means that some basepair sites will have more "degrees of freedom" than others (i.e., ways in which they can mutate without disrupting the gene's biological function in any way). Let's look at the four species with working GLO genes again:
TAC CCC GTG GAG GTG CGC TTC ACT CGG GCG GAC GAC ATC CTG CTG AGC CCC PIG
TAC CCC GTG GAG GTA CGC TTC ACT CGC GGG GAC GAC ATC CTG CTG AGC CCC BOS
TAC CCC GTA GAG GTG CGC TTC ACC CGA GGC GAT GAC ATT CTG CTG AGC CCC RAT
TAC CCC GTG GAG GTG CGC TTC ACC CGA GGT GAT GAC ATC CTG CTG AGC CCG MOUSE
T T T A T A T T T A T C C T T T T T T T T
A A A A A C A A A A A
G C G G G G G C C C
--- --- --1 --- --1 --- --- --1 --2 -12 --1 --- --1 --- --- --- --1
Under each site of the mouse DNA, I've listed the "alternative" bases which could be be substituted for the mouse base at that site WITHOUT ALTERING THE GENE'S FUNCTION (because of genetic code redundancy). And under that I show the "mutation map" of just those four species. Note that most of the "alternative" bases are in the third base of each codon, *and* that this is where all but one of the mutations have appeared. This is because these were the sites which were "free" to mutate in the way they did, because the mutation was genetically neutral. That doesn't mean that the first and second sites of each codon were immune from mutation, it's just that when mutations did occur at those sites, natural selection weeded them out quickly because they most likely "broke" the GLO gene for the individuals which received that mutuation. What we see above is the results after natural selection has already "filtered" the undesirable mutations and left the ones which "do no harm".
Additionally, the two sites which have mutated twice (i.e. have a "2" in the mutation map) are ones which had more "allowable" mutations. Also note that the sites which had the fewest allowable alternatives (only one alternate letter allowed) didn't have any mutations fix at those sites, which is unsurprising since a "safe" mutation would be less likely to occur there versus a site that "allowed" two or three alternatives.
All this is as predicted by evolutionary theory, you'll note.
It also explains the one anomoly of the original mutation map, which is that the mutation counts do tend to be higher at the third base of a codon.
However... What about the one exception? The pig DNA has had one mutation at a site which does not encode to exactly the same amino acid (which is the case for *all* the other ones). In the pig DNA, the GGG codon (mapping to Glycine) has changed to a GCG codon (mapping to Alanine). What's up with that? Well, one of two things. First and most likely, just as base values in codons have a built-in redundancy, so do the amino acids which make up the proteins which result from the DNA templates. In other words, certain amino acids can be substituted for other ones at some sites in given proteins without making any functional difference. (This "protein functional redundancy" also has implications for "evolutionary tracer" analysis, see here.) That may well be the case for Alanine versus Glycine in the GLO protein, but I'm not enough of a biochemist to be able to say. The other option is that it *does* make some difference in the function of the pig GLO protein, but not enough to "break" the vitamin-C synthesis (as proven by the fact that pigs *can* synthesize vitamin C). So one way or another, it's not a deal-breaker even though pig GLO will not be 100% identical to cow/mouse/rat GLO. It's yet another "allowable" mutation.
More interesting evolutionary observations: The number of mutational differences between pig/cow is 3, the number between mouse/rat is 4, and the difference between rat/cow is 7 -- all roughly as one would expect from the evolutionary relatedness of these animals (cows/pigs and rats/mice are each closer to each other than the rodents are to the ungulates).
Now let's take a close look at the guinea pig:
TAC CCT GTG GGG GTG CGC TTC ACC CGG GGG GAC GAC ATC CTG CTG AGC CCC GUIN PIG --- --1 --- -1- --- --- --- --- --1 --1 --1 --- --- --- --- --- ---The "mutation map" under the guinea pig DNA is compared to the mouse DNA. Fascinating: Note that four of the five mutations are in the third base of a codon, *and* are of the type "allowed" by the genetic code redundancy. This indicates strongly that most of the evolutionary divergence between guinea pigs and mice likely occurred while the guinea pig's ancestors still had a working GLO gene. This is the sort of prediction implied by the evolutionary theory which could be cross-checked by further research of various types, and if verified, would be yet further confirmation that evolutionary theory is likely correct. So far, evolutionary theory has been subjected to literally countless tests like this, large and small, and the vast majority of results have confirmed the evolutionary prediction. This track record is hard to explain if evolution is an invalid theory, as some assert...
Finally, let's look over the primate DNA and mutation map (relative to each other):
TAC CTG GTG GGG GTA CGC TTC ACC TGG AG* GAT GAC ATC CTA CTG AGC CCC HUMAN TAC CTG GTG GGG CTA CGC TTC ACC TGG AG* GAT GAC ATC CTA CTG AGC CCC CHIMPANZEE TAC CCG GTG GGG GTG CGC TTC ACC CAG AG* GAT GAC GTC CTA CTG AGC CCC ORANGUTAN TAA CCG GTG GGG GTG CGC TTC ACC CAA GG* GAT GAC ATC ATA CTG AGC CCC MACAQUE --1 -1- --- --- 1-1 --- --- --- 111 1-- --- --- 1-- 1-- --- --- ---Evolutionary theory predicts that because the GLO gene is "broken" in primates (i.e. is a pseudogene), mutations in it are highly likely to be neutral (i.e., make no difference, since it can't get much more broken), and thus mutations are just as likely to accumulate at any site as any other. Is that what we see? Yup. There's no obvious pattern to the mutations between primates in the above mutation map, and unlike the pig/cow/mouse/rat mutation map, the mutations aren't predominantly at the "safer" third base of a codon, nor of a type that would be "safe". In fact, one base has vanished entirely, but no biggie, the gene's already broken.
Also, although primates share a more recent common ancestor than cows/pigs/mice/rats, note that they've already racked up almost as many relative mutations as the cow/pig/mouse/rat DNA. This too is just as evolutionary theory predicts, because many mutations in a functional gene (GLO in this case) will be "non-safe" and weeded out by natural selection, making for a slower mutation fixation rate overall than in a pseudogene (as GLO is in primates) where natural selection doesn't "care" about the vast majority of mutations since *most* are neutral. So pseudogenes accumulate mutations faster than functional genes (even though rate of mutation *occurence* in both are likely the same).
Finally, note that there are ZERO mutational differences between the human DNA and the chimpanzee DNA, our nearest living relative.
I also see some interesting implications in the DNA sequences concerning which specific mutation fixed during what branch of the common-descent evolutionary tree for all the species represented, but reconstructing that would not only take another couple hours, at least, but would be a major bear to code in HTML, since I'd have to draw trees with annotations on the nodes... Bleugh.
In any case, I hope I've clarified some of the methods by which biologists find countless confirmations of evolution in DNA data. This is just a "baby" example, and to be more statistically valid would have to be done over much vaster sections of DNA sequences, but my intent was to demonstrate some of the concepts.
And if such a small amount of DNA as this can make small confirmations of evolutionary predictions, imagine the amount of confirmation from billion-basepair DNA data from each species compared across thousands of species... The amount of confirmatory discoveries for evolution from DNA analysis has already been vast, and promises to only grow in the future. For an overview of some of the different lines of evidence being studied, see The Journal of Molecular Evolution -- abstracts of all articles, current and back issues, can be browsed free online.
Grrr... Okay, make that "one". At this time of morning my tired eyes couldn't see the difference between a "C" and a "G" the first time around.
The modelling of the mantle flow over hundreds of millions of years is the central theme of the paper. It isn't something somebody might have added at the end.
In the past, when I've collaborated on work and the lead author wrote the work up drawing conclusions I found unfounded or wrong, I've given the author a choice - change the conclusions or take me off the author list (if they do the latter, of couse, the collaboration ends). It's the only ethical course of action for a co-author. See the statements of ethics I posted; If you co-author, you are responsible and accountable for the paper in its entirity.
I expect Baumgardner thought a paper in Science was too useful for his career to take such an action, ethically necessary though it is.
Gosh, how strange to find it necessary to proclaim the importance of personal accountability, and objective rather than situational ethics, on a conservative website.
Or Oscar Wilde "A Truth in art is that whose contradictory is also true." Yeah, that's it, he's an artist.
"Our doubts are not as to the truth or reality of evolution, but as to the origins of species, a technial, almost domestic problem. Any day that mystery may be solved. The discoveries of the last twenty-five years enable us for the first time to discuss these questions intelligently and on a basis of fact. That synthesis will follow on analysis, we do not and cannot doubt."
(Any mistakes in transcription are mine.)
If I find I have a bit of time, it would probably be interesting to see if that coincidence is actually statistically significant, or if it's roughly what we should expect from random chance.
Yes. And I meant to say "hoof prints".
Good, and please tell me if a deletion, a C , a T, and a G at the same location does not imply 3 mutations? Plus unless the macaque is a kissin cousin to the rat and mouse there is another 3 mutation spot.
That's where new species arise, but not what they are. By the dawn of the age of exploration, the human race had spread around the globe. The varying environments and the isolation of various subgroups from the rest of the gene pool had produced the beginnings of speciation processes that would eventually have gone to completion had we not re-discovered each other and re-connected all the gene pools. Now we're basically re-melding.
Thus, up to a somewhat blurry point, the process is reversible. Put in barriers to gene-mixing, differences arise. Take out the barriers, re-mixing can occur. (But in nature, it doesn't always. Sometimes the process once started simply runs away because of sexual selection pressures or a lack of situational viability of hybrid types.)
... or hybrids of the type similar to when horses and donkeys mate to produce mules.
The product (a mule) of horse-donkey hybridization is not a new species. It's not even fertile. (It's a useful farm animal combining some of the better points and skipping some of the drawbacks of its parent species.) You misinterpret the significance of the situation. That horses and donkeys are cross-fertile but produce sterile offspring is a sign that speciation has already occurred and relatively recently.
Despite all the similarities between the species and the near-compatibility that allows the production of mules, there is no way for horse and donkey populations to re-meld in the way humans are doing. They are on the other side of the speciation barrier and will go their separate ways now.
concisetraveler: Those are the most illuminated words you have said.
You liked that one? It fits.
Ol' Ted's still around. He's not posting (much) on the crevo threads any more, but he's here. I'll bet he enjoys reading all the comments about him, as well...
It's mostly the fault of the charlatans at AiG and ICR, who make a living telling lies to uneducated and highly susceptible children in grown-up bodies, people who just want to keep believing that fairy tales are real.
There are no "Missing links" because macro evolution can not occur. You have a few HIGHLY DISPUTED examples of what you say are macro evolution, but even most evolutionists will admit that the fossil record does not record the kind of information you would like for it to record.
You have no idea what most mainstream experts think on the subject, as that's exactly the kind of thing that AiG is lying to you about. As I've already shown you (to no particular effect), there's plenty of fossil evidence. This is not controversial out in the real world.
Some people here have an unduly high opinion of their place in the world.
Speciation is what you're going to see in a human lifetime. (But, as I told you, speciation is the irreversible event.)
Once again, Tempo and Mode of Speciation. You need this material. As long as you only know the AiG version of what evolution is, your arguments will be risible. Here's the part you're having trouble with right now:
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We still have populations that seem quite isolated. Have there been any studies about whether the Congo pygmies or the Kalahari bushmen mingle reproductively with the surrounding populations? The same question applies to other isolated groups like Australian natives, Amazonian tribes, and highlanders in remote Indonesian areas. Even if there were occasional "melding events," it may be that the bulk of such populations continue to be reproductively isolated, and if this continues, it's conceivable that speciation could result in a few tens of thousand of years.
It says on their news release it's the same paper. They say in
http://www.answersingenesis.org/docs2003/0821rate.asp
and I quote
There is now powerful independent confirmatory evidence that at least one episode of drastically accelerated decay has indeed been the case, building on the work of Dr Robert Gentry on helium retention in zircons. The landmark RATE paper,1, though technical, can be summarized as follows: (yadda)
Reference 1, cited is Humphreys, D. et al., Helium diffusion rates support accelerated nuclear decay, www.icr.org/research/icc03/pdf/Helium_ICC_7-22-03.pdf. That is the paper I've been analysing, the one where they buried the fact that the initial data, collected under conditions where the crystal was unaltered by heat, gave identical reuslts to previous values and did not support their hypothesis at all.
Common ancestry simply makes far more sense than "common designer." Why fill the ocean with fish, but then make whales from mammal parts? Why also put fossils in the rocks that seem to show land animals slowly losing their legs and becoming whales?
Why use something homologous to insectivore tree-dweller hands to make bat wings, but something like dinosaur claws to make bird wings, and just one incredibly stretched-out reptilian pinkie to support the pterodactyl wing? The supposed answer: you can't question the designer. (That's an answer!!??)
If something looks like design, it's proof of design. If it doesn't look like design, you're not allowed to notice or question. Can this be right?
The argument from design is not a theological argument, because we aren't necessarily talking about God. But any rebuttal of the design argument is theological, because it requires us to say "God wouldn't do it this way", and this is not legitimate.
It seems my comment bears repeating.
A thousand points of light. Whip Inflation Now! The answer my friend is blowin' in the wind. Puff the Magic Dragon, too.
Kudos to DittoJed2 and all her correspondents for a job exceedingly well done!
I'm confident that this "velvet glove" is more helpful to everyone here - especially the Lurkers - than any other style of debate.
I love you!
You love me!
We're a happy family!
[Thump!]
I don't know of any. The assault traditional lifestyles are under everywhere includes having the kids go off to school in the big city and marry outside the group. If the bushmen and pygmies aren't seeing that yet, they may soon.
"It is unwise to be too sure of one's own wisdom. It is healthy to be reminded that the strongest might weaken and the wisest might err."
Llamas and camels are of the same family, why not chimps and humans?
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