There is a passage that discusses the concept a bit. Henry Farfield Osborn was the directo

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There is a passage that discusses the concept a bit. Henry Farfield Osborn was the director and president of the American Museum of Natural History during the earlier part of this century. He was a powerful figure in paleontology. It continues: On the other hand, some of Osborn's diffuculties with prevailing evolutionary thinking in the 1920's were based on a dissatisfaction with natural selection as a blanket explanation for absolutely everything that has happened in evolution. And some of Osborn's problems derived from an even more common and vexatious source: basic misunderstandings between two disciplines. Both genetics and paleontology obviously bear on evolution, but otherwise there are no two more dissimilar activiteis than the finding, collecting and analysis of fossil bones and shells on the one hand, and figuring out the physical and chemical basis of heredity on the other. To this day the very elements of each discipline remain a closed book to the majority of practitioners of the other. Theodosius Dobzhansky, a geneticist and the closest thing to the "founding father" of the "synthetic theory of evolution," persistently criticized (derided is actually more like it) Osborn for writing:"Speciation is a normal and continuous process; it governs the greater part of the origin of species; it is apparently always adaptive. Mutation is an abnormal and irregular mode of origin, which while not infrequenly occuring in nature is not essentially an adaptive process; it is rather a disturbance of the regular course of speciation." It took another paleontologist, George Gaylord Simpson, to point outthat Osborn was simply using the word "mutation" in its *original* sense. The word first entered the paloentological literature in a paper by W. Waagen on ammonite evolution-a paper written in 1868. Waagen was discussing a series of ammonites (extinct moluscan relatives of the modern pearly nautilus) that he felt formed a linear ancestral-descendant lineage. Successive geological strata yielded slightly different forms, and these Waagen called "mutations." To "mutate" is simply to "change." "Mutation" simply popped up again as the natural choice of a word to describe spontaneous modifications in some anatomical feature of an individual organism-thus, presumably, a change in the underlying genetic material- when geneticists started plumbing the depths of heredity in the early 1900's. end quote The book was written to address the observation: For the paradox is this: species do not exhibit the sort of directional change through thier long histories, the sort of pattern that has been considered the true stuff of all evolutionary change. Yet species very commonly are members of lineages-trilobites, hominids, horses, dinosaurs-in which such directional change between species is a commonplace. Gould an I claimed that stasis-nonchange-is the dominant evolutionary theme in the fossil record. It is characteristic of most species that have ever lived. Adaptive change is relatively rare, and usually associated with speciation, thus typically rather rapid. Once a species appears, if it is successful at all, the fossil record shows that it will tend to hang on unchanged for vast stretches of time. And this, we saw, destroyed the backbone of the major argument of the modern "synthetic theory" of evolution-the argument maintaining that absolutely all the features of the history of life could be seen as constantly ongoing adjustments to ever-changing environmental conditions. (p.128) end quote Eldridge and Gould, 1985.


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