Whitlock Michael C, Fowler Kevin
Institute for Cell, Animal, and Population Biology, University of Edinburgh, Edinburgh, EH9 3JT, Scotland.
Department of Genetics and Biometry, University College London, 4 Stephenson Way, London, NW1 2HE, United Kingdom.
Evolution. 1996 Oct;50(5):1919-1926. doi: 10.1111/j.1558-5646.1996.tb03579.x.
The effects of inbreeding on the phenotypic variance within populations were measured in a set of 30 bottlenecked lines derived from a single source population of Drosophila melanogaster. Inbred lines had significant variance among lines in the amount of phenotypic variance within lines, for thorax length, and sternopleural bristle scores. When significance levels were corrected on an experimentwide basis, no line had significant increases in phenotypic variance for sternopleural bristle counts, although two lines had significant increases in thorax length variance. These results demonstrate that inbred lines cannot be treated as necessarily more uniform than outbred lines and that results on changes in variance due to inbreeding should be treated with caution unless there has been sufficient replication. These results also demonstrate the validity of an important assumption of models of evolution by variance-mediated mechanisms, such as the variance-induced peak-shift model.
在一组由单一黑腹果蝇源种群衍生而来的30个瓶颈品系中，测量了近亲繁殖对种群内表型方差的影响。对于胸长和腹侧板刚毛评分，近交系在品系内表型方差量上存在显著的品系间差异。当在全实验基础上校正显著性水平时，尽管有两个品系的胸长方差显著增加，但没有一个品系的腹侧板刚毛计数的表型方差有显著增加。这些结果表明，不能认为近交系必然比远交系更均匀，并且除非有足够的重复，否则因近亲繁殖导致的方差变化结果应谨慎对待。这些结果还证明了由方差介导机制（如方差诱导的峰移模型）的进化模型的一个重要假设的有效性。
