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6 See also: Gould, S. J. and Eldredge, N. 1977. Punctuated equilibria: the tempo and mode of evolution reconsidered. Paleobiology. 3:115–151. Levinton, J. S. and C. M. Simon. 1980. A critique of the punctuated equilibria model and implications for the detection of speciation in the fossil record. Systematic Zoology. 29:130–142.CrossRefGoogle Scholar

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15Mayr, E. 1963. Animal Species and Evolution. Belknap Press; Cambridge, Mass. 797 pp. (see pp. 578–580). Schopf, T. J. M. and L. S. Murphy. 1973. Protein polymorphism of the hybridizing seastars Asterias forbesi and Asterias vulgaris and implications for their evolution. Biol. Bull. 5:589–597. Other examples of rapid diversification are the various cases of species swarms in rift lake valleys, or Lake Baikal, or the Pontian (Caspian) cockles, the latter as recounted by S. M. Stanley. 1975. A theory of evolution above the species level. Proc. Nat. Acad. Sci. 72:646–650.CrossRefGoogle Scholar

16Bernard, F. 1895. Éléments de Paléontologie. J.-B. Baillière et Fils. Paris. 1168 pp. (Reprinted 1980 by Arno Press, New York. Partly reprinted 1895 in pamphlet form, and translated into English; 91 pp.; also reported to be in the Annual Report of the New York State Geological Survey. 14: 127–217. The critical passage on absence of finding intermediates is quoted in the editorial introduction to Eldredge and Gould, 1972; see ref. 5.)Google Scholar

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18 There is a lot of literature on this, and one easily accessible reference to a common marine taxon is: Schopf, T. J. M. and Dutton, A. R. 1976. Parallel clines in morphologic and genetic differentiation in a coastal zone marine invertebrate: the bryozoan Schizoporella errata. Paleobiology. 2:255–264.CrossRefGoogle Scholar

19Schopf, T. J. M. 1981. Evidence from molecular biology with regard to the rapidity of genomic change and species durations. In: Niklas, K. J., ed. Paleobotany, Paleoecology and Evolution: Festschrift for Harlan P. Banks. Praeger Pubs.; New York. Vol. 1, pp. 91–142.Google Scholar

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23 The diagram follows from a view expressed in 1976 that “On balance, it appears at least to Schopf that the data of this paper are most easily accepted into a model of dynamic, changing phyletic gradualism instead of a static, unchanging punctuated equilibrium.” (P. 263 in ref. 18.)Google Scholar

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30 Note for example that two-thirds or more of the width of present continental shelves of the world have had no sediment deposited for the past 10,000 or more years. The sediment on the present shelf chiefly is relict from earlier stands of sea level. Thus one dredges mastodon and mammoth teeth, for example, which date from several thousand years ago when sea level was 150 m lower. See p. 360 et seq. in Emery, K. O. and E. Uchupi. 1972. Western North Atlantic Ocean: topography, rocks, structure, water, life and sediments. American Association of Petroleum Geologists. Memoir 17. 532 pp.Google Scholar

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34 The reasons why taxa usually appear “suddenly” is poorly understood by those who support creationism and who usually have not had the opportunity for requisite advanced training in sedimentary geology, in chemical and physical diagenesis, and in paleontology. Perhaps an analogy with archeology would help. The fragmentary nature of human civilization is legion. Yet no one doubts that there were ancient cities of tens to hundreds of thousands of people. The disintegration of this record over a time scale of only a few thousand years must give one pause in trying to evaluate what ought to be the record for species, many of which were rare to begin with, which died out millions of years ago.Google Scholar

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41 This has been analyzed with respect to taxonomic survivorship curves by Sepkoski, J. J. Jr. 1975. Stratigraphic biases in the analysis of taxonomic survivorship. Paleobiology. 1:343–355.CrossRefGoogle Scholar

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43 The next couple of decades may see widespread assignment of marine taxa to subdivisions finer than a stage as the use of conodont zones becomes wide spread for Paleozoic and Triassic rocks, and as microfossils are increasingly used as the basis for zonal classification for the Jurassic and Cretaceous.Google Scholar

44 A cohort method of estimating durations was introduced by Raup, D. M. 1978. Cohort analysis of generic survivorship. Paleobiology. 4:1–15. However the first census point for each of the geologic system generic cohorts is after 90 percent of each cohort is no longer existing. (Unpublished series level data were reported to be “compatible” with system level data). Species durations were obtained in a backward calculation from inferred generic survivorship. This is not (nor was it represented to be) a direct measure of species durations.CrossRefGoogle Scholar

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47 “Nearly every major group of organisms has been discovered to have extensive complexes of sibling species. One example is the Hydrobiidae, a family of freshwater snails of world wide distribution. Assignment of the 11 genera and 92 species resisted correct assignment owing to ‘convergence in shell, radula, penis, and operculum’ (Davis 1979). Only characters of the female reproductive system proved to be reliable and confirmed by electrophoretic analysis of various taxa (G. M. Davis, personal communication 1980) …. And in another recent study, this one on a fiddler crab, Salmon et al. (1979, p. 190) concluded that ‘available evidence suggests that speciation in most of the other North American fiddler crabs has proceeded without significant morphological divergence’. What one finds at the molecular level may provide for rapid adaptation, and what one finds at the gross morphological level may be much more constrained by a variety of factors (e.g., structural design).” Schopf in ref. 19. Davis, G. M. 1979. The origin and evolution of the gastropod family Pomatiopsidae, with emphasis on the Mekong River Triculinae. Acad. Natural Sci. of Philadelphia. Monograph 20. Salmon, M. S., Ferris, S. D., Johnston, D., Hyatt, G., and Whitt, G. S. 1979. Behavioral and biochemical evidence for species distinctiveness in the fiddler crabs. Evolution. 33:182–191.Google ScholarPubMed

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57 Use of the fossil record for studies of speciation is sometimes justified on the grounds that it is the only record we have. For example, “Whether the fossil ‘species’ should be renamed morphospecies or whatever, study of their patterns of change through time must remain an integral part of any comprehensive evolutionary discipline.” (Hallam, A. 1981. Macroevolution conference report. Palaeontological Association Circular 103. pp. 6–8.) However if the answer to the question of what is the dominant mode of evolution is invested in an assumption about what these “morphospecies” represent, then it becomes a tautology and one can get any answer one wants, an obviously unsatisfactory state of affairs.Google Scholar

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64 “One might argue that genetic changes occur in a lineage through time, and thus the main impact of the views presented here is on the ‘arbitrary’ phyletic subdivision of a gradual transitional lineage (i.e., anagenesis). In fact, evidence for rapid genomic change also implies that phyletic splitting (i.e., cladogenesis) often should occur—that is, lineages need be ‘separated’ only for short periods of time (a few thousand years) in order to achieve reproductive isolation …. Thus, both phyletic transformation and phyletic splitting may occur far more often than has been generally recognized.” From Schopf, ref. 19.Google Scholar

65 Those who believe that the fossil record harbors any support for special creation should take no consolation from any arguments concerning punctuated equilibrium. To do so is to incorrectly understand the issues, only one of which concerns preservation and the fossil record^30,34.Google Scholar

Paleontology both benefits and suffers from an almost universal necessity to have its ideas conveyed in words instead of in chemical formulae or mathematics, and therefore it has the appearance of being readily accessible to the general reader who lacks training and experience in this field. This appearance of accessibility is both pleasant (it attracts interest to the field) and disconcerting (statements are wildly taken out of context). Of course one can believe that the fossil record supports creationism, just as one can believe that the earth is flat. But in either case the justification has no scientific basis whatsoever. The distortion of facts is as injurious to the understanding of science in general as it is disrespectful to religion in particular. Religion does not depend upon such distortions to justify its value in our society. Indeed religion can only lose respect in the long run if it is tied in the public mind to notions that are so patently false as the view that the fossil record in any way supports creationism.Google Scholar

It is ironic that the recent anti-evolution publicity should appear during the time that molecular biology and modern medical sciences are providing the most detailed account yet available of the evolutionary history of humans and other animals.Google Scholar

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