Evolution and Development of Polyphenism

p芬尼，大卫。这项研究将解决这样一个问题：为什么具有相同基因结构的个体有时会产生截然不同的形态？本文将以单足蟾蜍蝌蚪为模型系统进行研究。大脚蟾蜍蝌蚪是不寻常的，因为任何给定的个体都可以发育成两种不同的形态。在摄入了神仙虾或其他蝌蚪之后，典型的杂食性蝌蚪可能会改变它们的行为和发育，呈现出一种独特的肉食性形态，然后更快地蜕变成成年蟾蜍。这项研究的具体目标是：(1)确定是什么发育和生理过程导致了这两种形式的产生，(2)确定这种变异是否存在遗传基础，(3)确定在同一种群中维持这两种形式的环境因素。对于研究和教授其他发育生物学和生态学知识来说，蹼足蝌蚪是极好的模型动物。计划中的研究很重要，因为它将解决环境如何与生物体的基因在发育过程中相互作用以产生替代形式。这类研究将对发育过程和发育在使生物体适应不断变化的环境中的作用提供关键的见解。

Non-Technical AbstractProposal No. 9808641PI: Pfennig, DavidThis research will address the question: Why and how do individuals with the same genetic constitution sometimes produce strikingly different forms? The problem will be investigated by using spadefoot toad tadpoles as a model system. Spadefoot toad tadpoles are unusual in that any given individual can develop into two different forms. Following ingestion of fairy shrimp or other tadpoles, typical omnivorous tadpoles may alter their behavior and development to assume a distinctive carnivorous form, which then metamorphoses into an adult toad more quickly. The specific goals of the research would be to: (1) determine what developmental and physiological processes cause these two forms to be produced, (2) determine if there is a genetic basis to the variation, and (3) identify the environmental factors that maintain the two forms within the same population.Spadefoot tadpoles are excellent model animals for studying and teaching others about developmental biology and ecology. The planned research is important in that it will address how the environment interacts with an organism's genes during development to produce alternative forms. Such research will provide critical insight into developmental processes and the role of development in enabling organisms to adapt to changing environments.