Posted on 07/23/2008 6:52:40 AM PDT by Soliton
A dinosaur 'supertree' has been created that provides the most comprehensive picture ever produced of how dinosaurs evolved.
The tree shows the most likely pattern of evolution for 440 of the 600 known species of dinosaur and allows scientists to look for unusual patterns across the whole range of dinosaurs for the first time.
A study published today in the journal Proceedings of the Royal Society B claims the picture challenges opinions on how quickly dinosaurs expanded during the last 50 million years of their existence.
It has long been debated whether dinosaurs were part of the 'terrestrial revolution' that occurred some 100 million years ago during the Cretaceous period when birds, mammals, flowering plants, insects and reptiles underwent a rapid expansion.
But the supertree now suggests that dinosaurs were not expanding as actively as thought and that the apparent explosion of dinosaur diversity may be largely explained by a process known as 'sampling bias'.
The results show that all the bursts of diversification happened in the first 50 million years of the evolution of dinosaurs.
(Excerpt) Read more at inthenews.co.uk ...
2nd yawwwwwn, the old “the more we yell and the louder we yell, the more we hope folks will fall for it....”
Later expansions were not distinguishable from normal rates. This suggests dinosaurs did not take advantage of the new food supplies available during the Cretaceous terrestrial revolution - such as flowering plants, lizards, snakes, birds and mammals.
Like the Cambrian Explosion, evolution seems to occur at phenomenal rates very early, and then settle down dramatically. Is there any explanation? It seems odd. Also, wouldn't new food supplies seem to be a likely cause of specialization/speciation? But apparently it didn't work that way.
It all seems kind of random.
The overall lack of evolutionary change in dinosaur fossils, like everything else, is overwhelming. You can track a few small-scale changes, but overall the fossil record very clearly shows, not one overarching tree of life, but a forest of smaller trees without any reasonable linkages. Even when they claim to have found a significant transition it almost invariably has distinctive characteristics that cause the reporting scientists to admit it must have been a 'side branch' to the 'actual' common ancestor. In other words, the trunk and main limbs of the monophyletic evolutionary tree is perpetually missing.
Like the Cambrian Explosion, evolution seems to occur at phenomenal rates very early, and then settle down dramatically. Is there any explanation? It seems odd. Also, wouldn’t new food supplies seem to be a likely cause of specialization/speciation? But apparently it didn’t work that way.
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60 million years from now archaeologists digging in the earth will see one level with no civilization and suddenly there will be all the artifacts of civilization. there will be no transitional forms. it will appear that an extra terrestrial civilization landed on earth.
What happened?
An extra terrestrial civilization is on possible answer. Another would come if they have a copy of the bible. God himself who walked the earth in the form of his son Jesus. Jesus make all things possible to those who believe.
The tree shows the most likely pattern
Is this science or is it speculation?
A lack of metaphysical certitude ought not be construed as some sort of limitation of science. That's its strength.
Science follows the data. Nothing more.
Mostly the former, some of the latter
mostly the latter, some of the former
It seems a pity to go through all of this work when an upheaval is only one fossil find away.
Then you might as well toss out all scientific knowledge. Falsifiability is an essential characteristic of science.
Germ Theory is "only one find away" from an upheaval as well. Until then, I'll keep using antibiotics.
It seems a pity to go through all of this work when an upheaval is only one fossil find away.
Falsifiability is an essential part of a scientific theory, including germ theory.
Evolutionary theory is built on a foundation every bit as strong as that of germ theory. One discovery to the contrary would cast doubt on either one, as is true of all scientific theories. That doesn't make either less true.
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