Doctoral Dissertation Improvement: Phylogenetic Relationships and Gene Flow Among Southern African Baboons

普通狒狒（Papio）包括一系列地理上不同的形式或“半种”，虽然在外观和行为上彼此不同，但已知在它们的范围相遇的野外杂交。 狒狒在研究影响密切相关的杂交物种进化的分歧和网状化过程中特别有用，因为狒狒是唯一一种我们有详细的行为，遗传和形态数据以及长期研究杂交动力学的灵长类动物。 除此之外，对Papio的研究还可以为进化物种提供更直接的见解，比如早期人属，它们占据了类似的生态环境。 狒狒和早期的人属一样，都是陆生的、生态上通才的灵长类动物，它们在更新世非洲的大草原和林地中进化。 这些环境中气候驱动的变化影响了Papio的进化，很可能影响了Homo。 然而，狒狒保留了这些事件发生的时间和地理位置的遗传特征，而现代人类在进化过程中已经失去了这些特征。目前对Papio进化的了解主要来自对东非狒狒的研究。 然而，目前还不清楚这些东非狒狒是否代表了整个Papio。 因此，这项研究将侧重于南部非洲的形式，黄色和chacma狒狒，在赞比亚中部相互接触的进化关系和模式的基因流。 这两种形式的种群之间的进化关系将从线粒体DNA序列数据推断，而种群之间的遗传交换将使用线粒体DNA和一系列核基因组微卫星标记来辨别。 这项研究所解决的问题包括：南部非洲狒狒种群之间的关系是什么？ 这两种形式会杂交吗？如果会，那么最终的基因流动会采取什么样的模式？ 这种基因交换是否是由于雄性从纳塔尔群体分散到附近的其他群体（如非洲东部）所驱动的？ 这些问题的答案将有助于澄清Papio的分类，提高我们对狒狒物种之间的关系以及影响其进化的因素的理解，并深入了解这些过程如何影响相似灵长类物种的进化。狒狒通常用于生物医学，行为和遗传研究。 这些重要的模式生物之间的进化关系的准确理解是必要的，这样的研究。 该项目将为合作PI和本科生提供科学培训机会。 它还将促进美国和赞比亚科学家之间的专业接触和合作，这不是生物人类学家传统的研究地理重点。

Common baboons (Papio) comprise a series of geographically distinct forms or 'semi-species' that, while recognizably different from one another in appearance and behavior, are known to hybridize in the wild where their ranges meet. Papio is particularly useful in the study of the processes of divergence and reticulation that affect the evolution of closely-related, hybridizing species because baboons are the only primates for which we have detailed behavioral, genetic, and morphological data as well as long-term research in the dynamics of hybridization. In addition to this, studies of Papio can provide more direct insight into the evolution species, like early Homo, that occupy similar econiches. Baboons, like early Homo, are terrestrial, ecologically generalist primates that evolved in the savannas and woodlands of Pleistocene Africa. The climate-driven changes in these environments that affected the evolution of Papio may well have impacted Homo. However, baboons retain the genetic signature of the timing and geographic placement of these events that more recently evolved modern humans have lost.Current knowledge of the evolution of Papio largely comes from studies of eastern African baboons. However, it is unclear if these eastern African baboons are representative of Papio as a whole. This study, therefore, will focus on the evolutionary relationships and patterns of gene flow among southern African forms, the yellow and chacma baboons, which come into physical contact with one another in central Zambia. The evolutionary relationships among populations of these two forms will be inferred from mitochondrial DNA sequence data, while genetic exchange between populations will be discerned using both mitochondrial DNA and an array of nuclear genomic microsatellite markers. Questions addressed by this research include: what are the relationships among populations of southern African baboons? Do these two forms hybridize, and if so, what pattern does the resulting gene flow take? Is this genetic exchange driven by the dispersal of males from their natal groups into other nearby groups, as in eastern Africa? Answers to these questions will help clarify the taxonomy of Papio, improve our understanding of the relationships among baboon species and the factors that have affected their evolution, and provide insight into how such processes may impact the evolution of similar primate species.Baboons are commonly used in biomedical, behavioral, and genetic research. An accurate understanding of the evolutionary relationships among these important model organisms is necessary for such studies. This project will provide scientific training opportunities for the co-PI and undergraduate students. It will also promote professional contact and collaboration between scientists in the United States and Zambia, which has not been a traditional geographical focus of research by biological anthropologists.