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Originally Posted by notsofast
I think you have become ensnared by a logical fallacy. The final line here about how creationism must necessarily preclude “such taxa” is true only after your incredulous assumption of “intermediary anatomy” becomes established fact, a notion that not even the entire evolutionist world is ready to accept. Fossils can only suggest evolutionary relationships (e.g., your narrow list of chronological dinosauria) but, in the end, are unable to confirm those relationships.
T.S. Kemp in Fossils and Evolution sees the problem as being with either the fossil record or with the whole idea that evolution is gradual. He says, “the observed fossil pattern is invariably not compatible with a gradualistic evolutionary process.” The only evolutionist answer to this dilemma is to continue to advance one or both of two ad hoc hypotheses: 1) undiscovered fossil forms, or 2) unknown mechanisms of evolution, neither of which has been shown to be true or untrue.
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I think that first a discussion of Kemp's quote, and the matter of punctuated equilibrium is in order. Let us review the basic argument. According to some, the fossil record fails to support gradualistic morphologic change over time, and this assertion was largely at the heart of "punctuated equilibrium." The concept was first implied by Mayr, and later Stanley (1975, 1981, 1982), Gould & Eldredge (1977), Eldredge (1984, 1985), Eldredge & Stanley (1984) and Gould (1980, 1982) modified Mayr's work and promoted a model of evolutionary change in which any given lineage exhibited morphologic stasis over time, followed by rapid ontogenetic changes and diversification. Most vociferously championed by Gould, this viewpoint practically rejected the adaptive power of natural selection, but most egregiously of all, Gould presented it as revolutionary--a breathtaking new development hitherto unthinkable. Like any scientific postulate, tests explicitly geared to uphold or refute this concept of punctuated equilibrium have been carried out, and ironically, none have been more damning thereto, than quantitative analysis of morphologic change in fossil taxa. Considering that Gould and his colleagues claimed the fossil record as their staunchest support, this is most curious. If we give the Gouldian argument the benefit of the doubt, and exclude invertebrates (in which there are literally scores of gradualistic changes over time), and restrict our argument solely to the vertebrates, we can isolate a host of studies which have utterly failed to corroborate Gould's ideas. The most thorough and significant, are those of Paul Gingerich. His 1977, 1980 and 1982 reviews of Cenozoic megafauna entirely failed to demonstrate the sort of punctuational nature of evolutionary change that Gould et al would have predicted. Instead, Gingerich found a persistent trend towards gradual morphologic change over time. The same has been found in multiple studies of Cenozoic mammals, including: Hurzeler (1962), Chaline & Laurin (1986), Fahlbusch (1983), Harris & White (1979), MacFadden (1985), Cronin et al (1981), Maglio (1973) and last but not least Krishtalka & Stucky (1985). Furthermore, similar results have been observed in studies of freshwater teleosts from Miocene deposits of Nevada (Bell et al 1985). The natural question, then, is how does the presentation of punctuated equilibrium advanced by Gould et al, and subsequently parroted by creationists stand up to scrutiny of the fossil record? It doesn't at all. The salient lesson of these studies herein cited is that it is attention to morphology, and not taxonomic detail, which reveals the true nature of evolutionary change over time. How do you account for the significant amount of data refuting the punctuational argument that you have advanced?
As a side note, it must further be stressed that this entire argument forces a false dichotomy on evolution: it is either punctuational, or entirely gradualistic. Yet reality does not conform to this limited view. Indeed, G. G. Simpsons terms: bradyteyly, horoteyly, and tachyteyly are by far superior in expressing the plastic nature of rate of change amongst taxa (Simpson 1944, Carroll 1988).
Here are the appropriate references:
Stanley, S. M. 1975. A theory of evolution above the species level. Proceedings of the National Academy of Sciences 72: 646-650.
Stanley, S. M. 1981. The New Evolutionary Timetable: Fossils, Genes, and the Origins of Species. Basic Books, New York.
Stanley, S. M. 1982. Macroevolution adn the fossil record. Evolution 36: 460-473.
Gould, S. J. & Eldredge, N. 1977. Punctuated equilibria: the tempo and mode of evolution reconsidered. Paleobiology 3: 115-151.
Eldredge, N. 1984. Simpson's Inverse: Bradyteyly and the phenomenon of living fossils. In N. Eldredge and S. M. Stanley (eds), Models in Paleobiology: 82-115.
Eldredge, N. 1985. Time Frames. Simon & Schuster, New York.
Eldredge, N. & Stanley, S. M. 1984. Living Fossils. Springer-Verlag, Berlin, Heidelberg, New York, Tokyo.
Gould, S. J. 1980. The evolutionary biology of contstraint. Daedalus 109: 39-52.
Gould, S. J. 1982. The maning of punctuated equilibrium and its role in validating a hierarchical approach to macroevolution. In R. Milkman (ed.), Perspectives on Evolution: 83-104.
Gingerich, P. 1977. Patterns of evolution in the mammalian fossil record. In A. Hallam (ed.), Patterns of Evolution as Illustrated by the Fossil Record: 469-500.
Gingerich, P. 1980. Evolutionary patterns in early Cenozoic mammals. Annual Review of Earth and Planetary Sciences 8: 407-424.
Gingerich, P. 1982. Time resolution in mammalian evolution: Sampling, lineages, and faunal turnover. Third North American Paleontological Convention, Proceedings 1: 205-210.
Hurzeler, J. 1962. Kann die biologische Evolution. Summarized in Carroll, Vertebrate Paleontology & Evolution: 572-573.
Chaline, J. & Laurin, B. 1986. Phyletic gradualism in a European Plio-Pleistocene Mimonys lineage (Arvicolidae, Rodentia). Paleobiology 12: 203-216.
Fahlbusch, V. 1983. Makroevolution. Paleontographica 57: 213-230.
Harris, J. & White, T. D. 1979. The evolution of Plio-Pleistocene African Suidae. Tansaction sof the MAerican Philosphical Society 69" 1-128.
MacFadden, B. J. 1985. Patterns of phylogeny and rates of evolution in fossil horses: Hipparions from the Miocene and Pliocene of North America. Paleobiology 11: 245-257.
Cronin et al. 1981. Tempo and mode in hominid evolution. Nature 292: 113-122.
Maglio, V. J. 1973. Origin and evolution of the Elephantidae. Transactions of the American Philosophical Society, New Series 63: 1-149.
Krishtalka, L. & Stucky, R. K. 1985. Revision of the Wind River Faunas. Early Eocene of Central Wyoming. Part 7. Revision of Diacodexis (Mammalia, Artiodactylia). Annals of the Carnegie Museum 54: 413-486.
Bell et al. 1985. Patterns of temproal change in single morpholocial characters of a Miocene stickleback fish. Paleobiology 11: 258-271.
Carroll, R. L. 1988. Vertebrate Paleontology and Evolution. Freeman & Co., New York.
Simpson, G. G. 1944. Temp and Mode in Evolution. Columbia University Press, New York.
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