There is no evidence!
There is no fossil record!
It's all been debunked!
Posted on 10/07/2006 9:08:18 AM PDT by PatrickHenry
Evidence for punctuated equilibrium lies in the genetic sequences of many organisms, according to a study in this week's Science. Researchers report that about a third of reconstructed phylogenetic trees of animals, plants, and fungi reveal periods of rapid molecular evolution.
"We've never really known to what extent punctuated equilibrium is a general phenomenon in speciation," said Douglas Erwin of the National Museum of Natural History in Washington, D.C., who was not involved in the study. Since its introduction by Stephen Jay Gould and Niles Eldredge in the 1970s, the theory of punctuated equilibrium -- that evolution usually proceeds slowly but is punctuated by short bursts of rapid evolution associated with speciation -- has been extremely contentious among paleontologists and evolutionary biologists.
While most studies of punctuated equilibrium have come from analyses of the fossil record, Mark Pagel and his colleagues at the University of Reading, UK, instead examined phylogenetic trees generated from genetic sequences of closely related organisms.
Based on the number of speciation events and the nucleotide differences between species in each tree, the researchers used a statistical test to measure the amount of nucleotide divergence likely due to gradual evolution and the amount likely due to rapid changes around the time of speciation.
They found statistically significant evidence of punctuated evolution in 30% to 35% of the phylogenetic trees they examined. The remaining trees showed only evidence of gradual evolution.
Among the trees showing some evidence of punctuated equilibrium, the authors performed further tests to determine the size of the effect. They found that punctuated evolution could account for about 22% of nucleotide changes in the trees, leaving gradual evolution responsible for the other 78% of divergence between species.
Pagel and his colleagues were surprised that rapid evolution appears to contribute so much in some lineages, he said. "I would have maybe expected it to be half that much," he told The Scientist.
The researchers also found that rapid bursts of evolution appear to have occurred in many more plants and fungi than animals. Genetic alterations such as hybridization or changes in ploidy could allow rapid speciation, Pagel said, and these mechanisms are much more common in plants and fungi than in animals.
"Their result is pretty interesting, particularly the fact that they got so much more from plants and fungi than they did from animals, which I don't think most people would expect," Erwin told The Scientist.
However, it's possible that the analysis could be flawed, because the authors didn't take into account extinction rates in different phylogenetic trees when they determined the total number of speciation events, according to Douglas Futuyma of the State University of New York at Stony Brook, who was not involved in the study. But "they've got a very interesting case," he added. "I certainly think that this warrants more attention."
According to Pagel, the results suggest that other studies may have misdated some evolutionary events. Dates derived from molecular clocks assumed to have a slow, even tempo will place species divergences too far in the past, he said, since genetic change assumed to take place gradually may have happened very quickly.
"These kinds of events could really undo any notion of a molecular clock -- or at least one would have to be very careful about it," Futuyma told The Scientist.
Well known evolutionary mechanisms could account for rapid genetic change at speciation, Pagel said. Speciation often takes place when a population of organisms is isolated, which means that genetic drift in a small population or fast adaptation to a new niche could induce rapid evolutionary change.
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[Lots of links are in the original article, but not reproduced above.]
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If you're interested in learning about evolution, visit The List-O-Links.
If you'd like to understand the concept of speciation, visit Micro-evolution, Macro-evolution, and Speciation.
If you're serious about debating this issue, see How to argue against a scientific theory.
Evolution happened so fast it didn't leave any fossil evidence. In fact, the fossil record matches the CREATIONIST MODEL OF THE EARTH -- species appear suddenly and fully formed in the fossil record. Evolution is a religion, accepted on blind faith alone so evolutionists don't need any credible physical evidence.
Of course, there has to be a genetic mechanism by which evolution is possible. There needs to be mechanism by which information can be added to the genetic codes of lower organism in order for the lower organisms to develop into higher forms of life. Mutations are the only means by which that is possible. Yet, mutations are 99% detrimental and not ONE has ever been solely beneficial.
Take all this secular, atheistic propaganda to liberal websites and stopped wasting our time here. Become a liberal if you must, just keep such lies off FR.
Placemarker
It is a reflexive incantation they chant whenever they are overcome by the fear that a hob-goblin is about the "get them." Devoid of facts or evidence, and evincing a deep, profound primordial fear, they have no more significance than an expulsion of flatus in the face of a gale wind.
Oh, yes. That would be the scientific theory that holds that men were made out of mud and women out of ribs, that languages came about when people tried to make a really tall building and that all living land animals are descended from those that lived on a boat about 5000 years ago.
Syncopated Prevarication
"Oh, yes. That would be the scientific theory that holds that men were made out of mud and women out of ribs, that languages came about when people tried to make a really tall building and that all living land animals are descended from those that lived on a boat about 5000 years ago."
Boy! Did you read that wrong. Go back and read Genesis again, more carefully this time.
No, no, he means the one where the first man was made from an ash tree and the first woman from an alder.
Wait ... or does he mean the pixie version?
Hey, Sparky, here's the deal: I'll help you burn all the Darwinist books and papers if you bring the phlogiston.
I have a question for everyone here. Does believing in Evolution mean you cannot be a Conservative or even a Republican?
I have to admit, I sometimes feel like I belong to no party. For me Democrats are too close to socialism (or worse) for my tastes and yet I find on FR that so many people feel that if you believe in Evolution, you are not a Conservative. I don't have anything against Creationists except they wish to push their ideas off on our children as Science.
I cannot fully support a party that wishes to put ID into schools and I am wondering how do others out there deal with this dilemma. (Sorry if this has been asked before).
"Take all this secular, atheistic propaganda to liberal websites and stopped wasting our time here. Become a liberal if you must, just keep such lies off FR."
The folks who equate the theory of evolution with liberalism are the same folks who think that conservatism is equal to pentacostal Christianity.
There is nothing in conservatism that opposes evolution. There is nothing in conservatism that opposes the idea that things were created.
Conservatism is a political concept, not a religious or scientific concept.
Those who attempt to assign political beliefs to those who believe one thing or another regarding science are foolish and wrong.
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