Doctoral Dissertation Improvement: Development of Genomic Methods to Clarify the Evolution of Life History Trade-offs.

怀孕是生殖成功的标志，但历史上很少有人关注非人灵长类动物怀孕与生殖中的其他关键因素（如性选择、竞争和后代的亲代照顾）的关系。这项研究建立在其他研究的基础上，进一步发展了一个准确的新世界猴子系统发育，允许在进化背景下追踪生活史特征的变化。这项研究还促进了一名女性在科学方面的发展，并培养了高中生和本科生在实验室技术和遗传学方面的能力。该研究采用比较基因组学和系统发育的方法来检查怀孕在一个独特的研究人群中对生殖因素的作用。新世界猴的毛猴分支（狨猴、绢毛猴和戈尔迪猴）是研究妊娠进化的理想群体，因为它们每窝产出的后代数量存在自然变化。此外，狨猴表现出双胞胎生殖系嵌合，其中个体携带其（兄弟）幼崽的生殖细胞。此外，Goeldi猴转录组的产生允许检查数千个毛猴基因的进化史，明确地测试了与产仔数和嵌合有关的基因（例如与胎盘、生长、免疫和血管发生有关的基因）的假设，这些基因显示出与怀孕变化时间一致的适应性进化证据。测试关于哪些基因在毛毛猴谱系中发生了适应的假设，将填补关于这些灵长类动物所展示的迷人生物学的分子基础知识的空白，并将为未来的灵长类生物学研究奠定基础。最后，在一个血统良好的猴群中对个体进行基因分型，测试戈尔第的猴子是否保留了嵌合现象，尽管它失去了双胞胎的能力。这些发现将对理解亲代抚育的进化产生影响，也将为在进化过程中如何建立和维持免疫耐受提供线索。

Pregnancy is a hallmark of reproductive success, yet historically little attention has been paid to the study of nonhuman primate pregnancy relative to other key factors in reproduction such as sexual selection, competition, and parental care of offspring. This study builds on others to further develop an accurate New World monkey phylogeny that allows changes in life history traits to be traced within an evolutionary context. This research also advances a female in science and trains high school and undergraduate students in laboratory techniques and genetics.The research takes a comparative genomic and phylogenetic approach to examine the role of pregnancy with respect to reproductive factors within a unique study population. The callitrichine clade (marmosets, tamarins and Goeldi's monkeys) of New World monkeys is an ideal group in which to study the evolution of pregnancy because of natural variation in the number of offspring produced per litter. Moreover, marmosets exhibit twin-twin germline chimerism, in which individuals carry the reproductive cells of their (fraternal) littermates. In addition, the generation of a Goeldi's monkey transcriptome allows examination of the evolutionary history of thousands of genes in callitrichines, explicitly testing hypotheses that genes involved in litter size and chimerism (e.g. genes involved in placentation, growth, immunity, and vasculogenesis) show evidence of adaptive evolution coincident with the timing of the changes in pregnancy. Testing hypotheses about which genes have undergone adaptations in callitrichine lineages will fill a gap in knowledge about the molecular underpinnings of the fascinating biology exhibited by these primates, and will lay the foundation for future studies in primate biology. Finally, the genotyping of individuals within a well-pedigreed colony tests whether Goeldi's monkey has retained chimerism, despite having lost the ability to twin. These findings will have implications in understanding the evolution of parental care and also will provide clues into how immune tolerance is established and maintained during evolution.