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Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Species versus gene selection | Genet. Sei. Evol. 1989 21 247-248 Elsevier INRA -oiíĩíáli 247 Letter to the Editor Species versus gene selection s.c. Tsakas Agricultural University of Athens Department of Genetics Votanikos 118.55 Athens Greece and University of California at Irvine Department of Ecology and Evolutionary Ếiology Irvine GA 92717 USA received 17 January 1989 accepted 17 April 1989 Species selection has been recently promoted Gould Eldredge 1988a 1988b as the driving force in macroevolution and viewed as an explanation for the variability in rates observed both temporally and spatially at the phenotypic level. This has rekindled the contention between microevolutionists Maynard Smith 1987 1988 and macroevolutionists which has existed since Darwin s era. One of the main differences between micro molecular and macro phenotypic evolution is the stasis stage possible for the latter while the molecular evolution proceeds on as far as the lineage continues. Stabilizing selection Charlesworth et al. 1982 proposed by microevolutionists to explain this is countered by the proposal of species selection by macroevolutionists. Further complicating the matter are the existing exceptions which weaken both concepts. As Gould Eldredge so imaginatively put it Can we really hope to explain why the world holds more than a million species of insects and only a dozen or so of priapulids by relative adaptive success of their equally complex morphology alone It is a pleasant surprise to find that we are able to propose an answer to this and other difficult evolutionary questions such as Why for example do limpets lingula depnoi fishes horse shoe crabs dragonflies orthoptera tortoises crocodiles platypus and bats remain in comparative evolutionary stasis even though they live under variable environments compete with other species and have such long existences Is this the result of sampling or does a common denominator exist The answer can be found in the speciation burst hypothesis Tsakas David 1986 and .
