Daniel Smith
Posts: 970 Joined: Sep. 2007
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Quote (Reciprocating Bill @ Feb. 24 2009,18:11) | Quote (Daniel Smith @ Feb. 24 2009,20:22) | How would you know any of that without reading these scientists' works for yourself Bill?
Don't pre-judge what you know nothing about. It might make points here, but overall it makes you a smaller person.
You admire Gould for his open-mindedness, yet act the opposite. Sad. |
Don't be sad. Whatever my size, I rely upon serious scholars of biological science - e.g. Ernst Mayr in the his 1982 masterwork The Growth of Biological Thought and Stephen Jay Gould in his The Structure of Evolutionary Theory, among others - for guidance regarding where to put my limited time and energy, not obtuse science deniers with zero credibility (you). Mayr, for example, summarized several facts of evolution, then stated:
"These findings completely refuted the antiselectionist, saltational evolutionary theories of de Vries and Bateson. Curiously, this by no means spelled the end of saltationism, which continued for several decades to have substantial support, as for instance by the geneticist Goldschmidt, the paleontologist Schindewolf...the botanist Willis, and some of the philosophers. Eventually it was universally accepted that an origin of species and higher taxa through individuals does not occur, except in the form of polyploidy (principally in plants). The phenomenon which the adherents of macrogenesis had used as support could now be readily explained in terms of gradual evolution. Particularly important...was the recognition of the importance of two previously neglected evolutionary processes: drastically different rates of evolution in different organisms and populations, and evolutionary changes in small, isolated populations. It was not until the 1940s and 50s that well-argued defenses of macrogenesis disappeared from the evolutionary literature in the wake of the evolutionary synthesis." (p. 551)
"The new understanding of the nature of populations and of species enabled the naturalists to solve the age-old problem of speciation - a problem that had been insoluble for those who looked for the solution at the level of genes or genotypes. At that level the only solution is instantaneous speciation by a drastic mutation or other unknown processes. As de Vries had stated, "the theory of mutation assumes that new species and varieties are produced from existing forms by certain leaps." Or as Goldschmidt had stated, "The decisive leap in evolution, the first step toward macroevolution, the step from one species to another, requires another evolutionary method [that is, the origin of hopeful monsters] than that of sheer accumulation of micro mutations." The naturalists realized that the essential element of the speciation process is not the physiological mechanism involved (genes or chromosomes) but the incipient species, that is, a population. Geographic speciation, consequently, was defined by Mayr in terms of populations: "A new species develops if a population which has become geographically isolated from its parental species acquires during this period of isolation characters which promote or guarantee reproductive isolation when the external barriers break down.'" (p. 562)
In short, Goldschmidt, Schindewolf, Bateson and other saltationists are part of scientific history, obsolete for a half-century and longer, and no longer relevant to current thinking. I don't have time for that.
[edit to replace mistaken "not" with "now."] |
I don't think you realize how outdated the idea of speciation via the "sheer accumulation of micro mutations" is.
Maybe you should try to find a recent paper that postulates that mechanism for the origin of any novel system.
You won't find many papers anymore that don't appeal to gene duplications, whole genome duplications, horizontal gene transfer, genetic reshuffling and the like, as opposed to an accumulation of micro mutations.
-------------- "If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance." Orville Wright
"The presence or absence of a creative super-intelligence is unequivocally a scientific question." Richard Dawkins
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