6. Common errors in discussion of PE Many errors can be found in discussion of the concept of PE. G&E 1977 point out several of these.
PE is not mutually exclusive of phyletic gradualism. Gould and Eldredge take pains to explicitly point out that PE is an expansive theory, not an exclusive one (1977). PE sometimes is claimed to be a theory resting upon the lack of evidence rather than upon evidence. This is a curious, but false claim, since Eldredge and Gould spent a significant portion of their original work examining two separate lines of evidence (one involving pulmonate gastropods, the other one involving Phacopsid trilobites) demonstrating the issues behind PE (1972). Similarly, discussion of actual paleontological evidence consumes a significant proportion of pages in Gould and Eldredge 1977. This also answers those who claimed that E&G said that PE was unverifiable. PE is essentially and exclusively directed to questions at the level of speciation and processes affecting species. The basis of PE is the neontological theory of peripatric speciation. The criteria by which "punctuations" are recognized by Gould and Eldredge involve temporal issues and geographic issues. PE is not expected to be as useful at lower or higher levels of change. PE is by no means either synonymous with "saltationism", nor did Gould's essay on Richard Goldschmidt "link" PE with Goldschmidt's "hopeful monster" conjecture. Gould wrote an article that has caused much confusion. "Return of the hopeful monsters" sought to point out that a hatchet job had been done on some of the concepts that Richard Goldschmidt had formulated. The discussion of systemic mutations as mutations which affect rate or timing of development has caused many people to assume that Gould was somehow linking PE to this concept. A close reading of the article shows this to not be the case. Gould and Eldredge did not specify any particular genetic mechanism for PE. PE does not require large scale mutations. PE is not a saltational theory of evolution. The emphasis upon applying consequences of peripatric speciation to paleontology shows this critique to be unfounded. PE is no more saltational than peripatric speciation is in study of modern organisms. 7. References Dawkins, Richard. 1986. The Blind Watchmaker. New York, New York: W.W. Norton Co. Eldredge, N., & Gould, S. J. 1972. Punctuated equilibria: an alternative to phyletic gradualism. In: Models In Paleobiology (Ed. by T. J. M. Schopf). Gould, S. J., & Eldredge, N. 1977. Punctuated equilibria: the tempo and mode of evolution reconsidered. Paleobiology, 3, 115-151. Gould, S. J. 1980. Return of the Hopeful Monster. In: The Panda's Thumb. New York, New York: W.W. Norton Co. pp. 186-193. 8. Acknowledgements Chris Colby provided a cogent and detailed critique of the first draft, pointing out the "gene flow vs. homeostasis" argument in E&G 1972 among many other points. Many of his points remain to be incorporated, which says more about the extent of my free time rather than the importance of those points. Chris Nedin suggested several changes incorporated here, including expansion of the discussion of Darwin in relation to phyletic gradualism. I still need to check out The Beak of the Finch for examples of (relatively) rapid evolutionary change. I thank the Oxford Text Archive for providing a free e-text of Origin of Species, first edition. This makes looking up interesting passages much easier than in the paper versions. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] Visit IAGI Website: http://iagi.or.id IAGI-net Archive 1: http://www.mail-archive.com/iagi-net%40iagi.or.id/ IAGI-net Archive 2: http://groups.yahoo.com/group/iagi Komisi Sedimentologi (FOSI) : F. Hasan Sidi([EMAIL PROTECTED])-http://fosi.iagi.or.id Komisi SDM/Pendidikan : Edy Sunardi([EMAIL PROTECTED]) Komisi Karst : Hanang Samodra([EMAIL PROTECTED]) Komisi Sertifikasi : M. Suryowibowo([EMAIL PROTECTED]) Komisi OTODA : Ridwan Djamaluddin([EMAIL PROTECTED] atau [EMAIL PROTECTED]), Arif Zardi Dahlius([EMAIL PROTECTED]) Komisi Database Geologi : Aria A. Mulhadiono([EMAIL PROTECTED]) ---------------------------------------------------------------------
