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http://macroevolution.narod.ru/dawkins_watchmaker/watchmaker.html#09

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http://macroevolution.narod.ru/dawkins_watchmaker/watchmaker.html#09

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  1. http://macroevolution.narod.ru/dawkins_watchmaker/watchmaker.html#09http://macroevolution.narod.ru/dawkins_watchmaker/watchmaker.html#09

  2. I have since, for instance in The Blind Watchmaker, become somewhat petulant - perhaps too much so - over the way the theory of punctuated equilibrium has been oversold. If this has hurt anybody's feelings, I regret it. They may like to note that, at least in 1976, my heart was in the right place.[61]** Progressive evolution may be not so much a steady upward climb as a series of discrete steps from stable plateau to stable plateau

  3. 1993 retrospective (21 years later): “We realized that a standard biological account … would yield stasis and punctuation when properly scaled into the vastness of geological time. For small populations speciating away from a central mass in tens or hundreds of thousands of years, will translate in almost every geological circumstance as a punctuation on a bedding plane, not gradual change up a hill of sediment, whereas stasis should characterize the long and recoverable history of successful central populations”. (speciation occurs off stage) “We now realize how poorly we initially grasped the implications of our original argument; we thank our colleagues… for several extensions”. We devised a motto: “Stasis is data”. “…stasis, inevitably read as absence of evolution, had always been treated as a non-subject”.

  4. Stasis is harder to explain… Why would some lineages not change? • Mutation, drift, and natural selection must be happening… • Yet, there are several examples sometimes called “living fossils”:

  5. Triops(tadpole shrimp):temporary pools in arid regions of Eurasia and northern Africashows no evident morphological change since the Triassic

  6. Stasis in the bivalve Macrocallistamaculata: No measurable morphological change over 17 my

  7. Coelocanths = lobe finned fishes: originated in Devonian, thought to have gone extinct in Cretaceous living species discovered in 1938—little morphological difference

  8. Gingko, Jurassic (200 mya) to recent

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