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Macroevolution is evolution on a scale of separated gene pools.〔Matzke, Nicholas J. and Paul R. Gross. 2006. Analyzing Critical Analysis: The Fallback Antievolutionist Strategy. ''In'' Eugenie Scott and Glenn Branch, ''Not in Our Classrooms: Why Intelligent Design is Wrong for Our Schools'', Beacon Press, Boston ISBN 0807032786〕 Macroevolutionary studies focus on change that occurs at or above the level of species, in contrast with microevolution, which refers to smaller evolutionary changes (typically described as changes in allele frequencies) ''within'' a species or population. Macroevolution and microevolution describe fundamentally identical processes on different time scales.〔〔 The process of speciation may fall within the purview of either, depending on the forces thought to drive it. Paleontology, evolutionary developmental biology, comparative genomics and genomic phylostratigraphy contribute most of the evidence for the patterns and processes that can be classified as macroevolution. An example of macroevolution is the appearance of feathers during the evolution of birds from theropod dinosaurs, when now viewed at a distance from the future, although as they arose the developing changes would be deemed microevolution. The evolutionary course of Equidae (wide family including all horses and related animals) is often viewed as a typical example of macroevolution again from the broad viewpoint after a notable accumulation of previously microevolutionary changes. The earliest known genus, ''Hyracotherium'' (now reclassified as a palaeothere), was a browsing herbivore animal resembling a dog that lived in the early Cenozoic. The preferred evolutionary explanation is that as its habitat transformed into an open arid grassland (which we can reconstruct through pollen and seed records), selective pressure acted so that the animal become a fast grazer (as recorded by dentition changes etc). Thus elongation of legs and head as well as reduction of toes gradually occurred, producing the only extant genus of Equidae, ''Equus''.〔 ==Origin of the term== Russian entomologist Yuri Filipchenko first coined the terms "macroevolution" and "microevolution" in 1927 in his German language work, "Variabilität und Variation". Since the inception of the two terms, their meanings have been revised several times and the term macroevolution fell into limited disfavour when it was taken over by such writers as the geneticist Richard Goldschmidt (1940) and the paleontologist Otto Schindewolf to describe their orthogenetic theories.〔(Macroevolution: Its definition, Philosophy and History )〕 A more practical definition of the term describes it as changes occurring on geological time scales, in contrast to microevolution, which occurs on the timescale of human lifetimes. This definition reflects the spectrum between micro- and macro-evolution, whilst leaving a clear difference between the terms: because the geological record rarely has a resolution better than 10,000 years, and humans rarely live longer than 100 years, "meso-evolution" is never observed.〔 While such evolutionary biologists Theodosius Dobzhansky, Bernhard Rensch and Ernst Mayr use the term, many neo-Darwinian do not, preferring instead to talk of evolution as changes in allele frequencies without mention of the level of the changes (above species level or below). Use of the term is most common in the continental European traditions (as Dobzhansky, Mayr, Rensch, Goldschmidt and Schindewolf were) and less common in the Anglo-American tradition (such as John Maynard Smith and Richard Dawkins). Hence, use of the term "macroevolution" is sometimes wrongly used as a litmus test of whether the writer is "properly" neo-Darwinian or not.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「macroevolution」の詳細全文を読む スポンサード リンク
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