Letters.Specious definitions? In grad school, I read and learned from Ernst Mayr's Populations, Species, and Evolution (1963, 1970, Harvard University Press The Harvard University Press is a publishing house, a division of Harvard University, that is highly respected in academic publishing. It was established on January 13, 1913. In 2005, it published 220 new titles. ). I think that "Alarming butterflies and go-getter fish" (SN: 7/21/01, p. 42) extremely simplifies Mayr's position on speciation speciation Formation of new and distinct species, whereby a single evolutionary line splits into two or more genetically independent ones. One of the fundamental processes of evolution, speciation may occur in many ways. . The article says that Mayr focuses solely on geographic separation, "allopathic Allopathic Pertaining to conventional medical treatment of disease symptoms that uses substances or techniques to oppose or suppress the symptoms. Mentioned in: Traditional Chinese Medicine speciation." This ignores the fact that Mayr discussed a variety of other isolating mechanisms besides allopathic speciation. The article also discusses possible genetic differences between populations of R. pomonella but offers no evidence that those allegedly different genetic populations are incapable of interbreeding interbreeding crossbreeding, as between half-breds. . Thomas W. Kavanagh Indiana University Bloomington, Ind. I noticed in "Alarming butterflies and go-getter fish" an example of an oft-repeated misinterpretation of the theory of evolution. The article states that some butterflies "happened upon" color variations that resembled the older species. Evolution works negatively rather than positively: Those ancestors that didn't exhibit the color variation were more likely to be killed by predators and less likely to produce offspring. The butterflies that exhibited color variations did not happen upon them as if they went shopping for new clothes. They manifested a mutation that happened to give them a survival advantage. They had no choice in the matter. Chip Wolfe Austin, Texas Flower cower cow·er intr.v. cow·ered, cow·er·ing, cow·ers To cringe in fear. [Middle English couren, of Scandinavian origin. This concerns the story discussing the ability of flowers to protect their reproductive parts by closing up during a rain storm ("Shut up! A thunderstorm's on the way," SN: 7/21/01, p. 41). I recently observed what may be other mechanisms to achieve the same end in flowers that can't close up. As a storm approaches, Queen Anne's lace Queen Anne's lace or wild carrot, herb (Daucus carota) of the family Umbelliferae (carrot family), native to the Old World but naturalized and often weedy throughout North America. dips its flat umbels Umbels is a flower cluster having stalked flowers arranged singly along an elongated unbranched axis, as in the lily of the valley, in which all the individual flower stalks arise in a cluster at the top of the peduncle and are of about equal length. to a vertical position to escape as much water as possible. The position seems not to be caused by the weight of the water on the flower, as it often occurs before rain strikes. Moth mullein in the same situation, since it can't close, turns its face toward the ground. John T. Roberts Charlottesville, Va. |
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