"The nature and cause of transpecific evolution has been a highly controversial subject during the first half of this century. The proponents of the synthetic theory maintain that all evolution is due to the accumulation of small genetic changes, guided by natural selection, and that transpecific evolution is nothing but an extrapolation and magnification of the events that take place within populations and species. A well-informed minority,...maintained...that neither evolution within species, nor geographic speciation could explain the phenomena of "macroevolution" or as it is better called transpecific evolution."
Date: Mon Jun 28 1993 21:01:00 From: Raphael Carter To: Mark Arvid Johnson Subj: Allele frequency definiti Attr: evolution --------------------------------= Dixit Mark Arvid Johnson ad Jeff Doles in re Allele frequency definiti: =-
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There is no unequivocal evidence that microvariation (changes in allele frequencies) can be extrapolated up to what is called evolution....
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"There was, however, a singular absence of any proof that macro-evolutionary phenomena are indeed caused by the same genetic mechanism that characterizes intrapopulational variation" Ernst Mayer, _Toward a New Philosophy of Biology_, p.399Although I am only a layman and quite unqualified for a full-scale defense of evolution on all fronts, since I am currently reading Mayr's [note sp] _Toward a New Philosophy of Biology_ I thought I'd point out that this quote is out of context. The "_was_" should be a tip-off that Mayr is talking about a state of affairs that used to obtain, but no longer does. In fact he is talking about the early days of the evolutionary synthesis, ca. 1920-1940. Here is the same quotation with more context:
...all the geneticists were able to document was that macroevolution- ary phenomena are consistent with the known genetic processes. There was, however, a singular absence of any proof that macroevolutionary phenomena are indeed caused by the same genetic mechanisms that char- acterize intrapopulational variation.
A study of the writings published during the evolutionary synthesis [note that Mayr here identifies the time about which he's writing] reveals that the problems of macroevolution were rather neglected. This had primarily two reasons. The first was that, _prior_to_the_ _development_of_molecular_biology_, macroevolutionary phenomena were quite inaccessible through the classical genetic methods, because one cannot cross representatives of higher taxa. [emphasis mine]Note that Mayr lists a form of evidence, molecular biology, which addresses the very lack mentioned in the out-of-context quote you gave.