Evolution of Bill Size Polymorphism in the African Finch Pyrenestes

NSF拨款BSR-8817336，题为“非洲比利牛斯雀Bill多态性的进化”的基础和应用方面。是什么在自然种群中产生和保持变异是生物学中最基本和最重要的问题之一，在物种中发现的变异类型中，也许没有一个像多态性的发生那样引起了如此多的争论。当两个或两个以上不同的杂交形式在一个群体中同时出现时，就会出现多态性。尽管经过了几十年的研究，但很少有实例能够理解产生多态性的机制。非洲赤翅雀（Pyrenestes ostrinus）是为数不多的已知物种之一，其多态性与不同的资源利用有关。在非洲热带森林三年的前期研究的基础上，提出了确定多态性的遗传和生态基础的研究努力。因此，该研究将为检验当前维持多态性的理论模型提供经验基础，并大大提高我们对动物物种中如何维持变异的理解。虽然热带森林只覆盖了世界陆地表面的7%，但它们却包含了所有已知物种的一半以上。热带森林在调节地球气候方面发挥着关键作用，为农业提供了重要的遗传物质储藏库，是许多重要药物的来源，并提供宝贵的可再生经济资源。尽管它们很重要，但它们正在加速消失。为了使保护工作取得成功，迫切需要热带雨林的基本生物资料。作为拟议的比利牛斯山脉研究的一部分，还将收集对热带雨林保护至关重要的关键信息。

Basic and applied aspects of NSF grant BSR-8817336, entitled "Evolution of Bill Polymorphism in the African Finch Pyrenestes." What produces and maintains variation in natural populations is one of the most fundamental and important questions in biology, of the types of variation found in species perhaps none has generated as much debate as the occurrence of polymorphism. Polymorphism occur when two or more distinct interbreeding forms co-occur within a single population. Despite decades of research there are few instances where the mechanisms producing polymorphism are understood. The African estrildid finch Pyrenestes ostrinus represents one of the few known species where a polymorphism is associated with differential resource use. Building on three years of prior research in the tropical forests of Africa proposed research endeavors to determine the genetic and ecological basis of the polymorphism. In so doing the research should provide an empirical foundation for testing current theoretical models for maintaining polymorphism and greatly improve our understanding of how variation is maintained in animals species. While only seven percent of the world's land surface is covered by tropical forests they contain over half of all known species. Tropical forests play a critical role in regulating the earth's climate, provide important storehouses of genetic material for agriculture, are the source of many important pharmaceuticals and provide valuable renewable economic resources. Despite their importance they are disappearing at an accelerating rate. For conservation efforts to be successful there is a critical need for basic biological information tropical rainforests. As part of the proposed research on Pyrenestes critical information important for rainforest conservation will also be collected.