The Role of Development in Reaction Norm Evolution

“反应规范”是对环境变化时特征如何变化的描述，例如，昆虫、哺乳动物和其他生物的成年体型如何因早期营养的变化而变化。这种变异往往是深刻的，在许多情况下，变异表现出适应特定环境的额外特征。反应规范具有遗传基础，不同基因组的生物体通过反应规范适应环境的能力不同。由于个体之间的这种遗传差异，应该有可能通过选择改变反应规范，从而改变并可能提高生物体对可变环境的适应能力。本研究将通过研究两种不同生长特征鳞翅目昆虫体型与营养关系的遗传反应规范来验证这一假设。这项工作将首次研究决定体型的潜在发育生理学的遗传学。这一生理过程包括控制动物何时开始蜕变为成年动物的激素分泌模式。由于PI在该系统的发育生理学方面的早期工作，在该系统中生长和成熟的发育控制比在几乎任何其他生物体中都更好地理解。这使我们能够启动关于遗传变异如何影响控制最终成年体型的发育过程的变异的拟议调查。这项工作将增强我们对基因和发育如何调节导致体型变化的反应规范的理解。

A "reaction norm" is a description of how a trait changes when the environment changes, for instance, how adult body size varies due to variation early nutrition in insects, mammals, and other organisms. Such variation is often profound and in many cases the variants exhibit additional traits that are adaptations to a particular environment. Reaction norms have a genetic basis, and organisms with different genomes differ in their ability to adapt to their environment via a reaction norm. Because of such genetic differences among individuals, it should be possible to change the reaction norm by selection and therefore change and perhaps improve the adaptation of organisms to a variable environment. The proposed work will test this hypothesis by studying the genetics of the reaction norm of body size in relation to nutrition in two species of Lepidoptera with different growth characteristics. This work will, for the first time, study the genetics of the underlying developmental physiology that determines body size. This physiology consists of patterns of hormone secretion that control when the animal begins metamorphosis to the adult. Because of the PI's earlier work on the developmental physiology of this system, the developmental control of growth and maturation are better understood in this system than in almost any other organism. This enables us to initiate the proposed investigation of how genetic variation affects variation of the developmental processes that control the final adult body size. This work will enhance our understanding of how the reaction norms that lead to variation in body size are regulated by genetics and development.