Dissertation Research: Genetic Determination of Parentage in Cooperative Groups

12年来，PI研究了几个种群， 弗伦斯（Campylorhynchus griseus），实践合作 在委内瑞拉繁殖。 这些鸟生活在大家庭中 在永久性的公共领土上的群体，一种习惯， 广泛分布于热带鸟类中。 这些人口是 尤其是对上述进化论观点的检验 因为它有效地增加了 可以生产的年轻人。 家谱可供85 该物种的群体（超过700标记的个人）在两个 不同的栖息地类型 使用新开发的DNA指纹技术， 将确定假定的繁殖者是否是唯一的鸟类 在这些家庭群体中繁殖， 非繁殖的帮手帮助抚养兄弟姐妹。 本测试 现在将基于基因的决定性证据， 材料本身，而不是基于错误的推论， 行为观察 他们将记录下 亲子关系在群体内部和群体之间共享， 模型和计算机模拟将量化潜在的 在社会关系中，除了主要的一对父母之外， 组 他们将继续进行实地实验， 竞争生产育种岗位的过程， 对掠食者的群体防御， 在群体中繁殖的优势。 他们还将探讨 短距离传播对遗传的影响 种群的结构和独特性，使用限制- 片段长度多态性（RFLP）分析和我们的长期 关于人口之间扩散趋势差异的数据。

For twelve years the PIs have studied several populations of wrens (Campylorhynchus griseus) that practice cooperative breeding in Venezuela. These birds live in extended family groups on permanent communal territories, a habit that is widespread among tropical birds. These populations are an especially revealing test case of the above evolutionary ideas about cooperation because it so effectively increases the number of young that can be produced. Genealogies are available for 85 groups (more than 700 marked individuals) of this species in two distinct habitat types. Using newly-developed DNA fingerprinting techniques, the PIs will establish whether the presumed breeders are the only birds reproducing in these family groups, and whether putative nonbreeding helpers are aiding in rearing siblings. This test will now be based on conclusive evidence from the genetic material itself rather than on fallible inferences based on behavioral observation. They will document the extent to which parentage is shared within and between groups, and analytical models and computer simulations will quantify the potential importance of parentage shared beyond a principal pair in social groups. They will continue field experiments examining the processes of competition for productive breeding positions and group defense against predators, the suspected mechanism of the advantage of breeding in a group. They will also explore the implications of short-distance dispersal for the genetic structure and distinctness of populations, using restriction- fragment-length polymorphism (RFLP) analyses and our long-term data on differences in dispersal tendencies between populations.