Using Artificial Correlational Selection to Evaluate the Causes of Sexual Dimorphism

使用人工相关选择来评估性别二态性的原因

• 批准号: 0210971
• 负责人: Lynda Delph
• 金额: --
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0210971&HistoricalAwards=false
• 关键词: Using; Artificial; Correlational; Selection; Evaluate

Differences between the sexes are pervasive in both animals and plants. Such dimorphism can result from selection directly on a trait or it can be a result of genetic correlations between traits. The investigators will test the hypothesis that multiple characters exhibit sex differences in the dioecious plant Silene latifolia, because of genetic correlations between traits. This hypothesis will be investigated with two quantitative-genetic experiments. The first incorporates a set of controlled crosses and subsequent measures of progeny, to determine the pattern and magnitude of genetic covariances among traits. The second experiment will involve artificial selection to investigate how labile the genetic correlations are between flower traits and physiological traits. They will select on the combination of traits rather than on individual traits to alter the correlation between traits, the most powerful way of breaking correlations.These experiments are centered on measuring and altering genetic correlations. These correlations can occur because of pleiotropy, in which one gene affects more than one trait, or because of linkage, in which the genes affecting traits are inherited together. The first of these, pleiotropy, leads to long-term correlations between traits, whereas linkage can be easily broken by selection. If the investigators are unable to break the correlation between traits, then this will lend credence to the hypothesis that pleiotropy contributes to patterns of genetic correlation and differences between the sexes.

两性之间的差异在动物和植物中都很普遍。 这种二态性可能是由于选择直接作用于一个性状，也可能是性状之间遗传相关性的结果。 研究人员将检验一个假设，即在雌雄异株植物宽叶蝇子草中，由于性状之间的遗传相关性，多个性状表现出性别差异。 这一假设将通过两个定量遗传实验进行研究。 第一个结合了一组控制的杂交和后代的后续措施，以确定性状之间的遗传协方差的模式和幅度。 第二个实验将涉及人工选择，以调查花性状和生理性状之间的遗传相关性有多不稳定。 他们会选择性状的组合而不是单个性状来改变性状之间的相关性，这是打破相关性的最有效方法。这些实验的核心是测量和改变遗传相关性。 这些相关性可能是因为多效性，即一个基因影响一个以上的性状，或者是因为连锁，即影响性状的基因一起遗传。 第一种是多效性，它导致性状之间的长期相关性，而连锁可以通过选择很容易地打破。 如果研究人员无法打破性状之间的相关性，那么这将使多效性有助于遗传相关模式和性别差异的假设更加可信。