DISSERTATION RESEARCH: Reassessing the role of the Great American Biotic Interchange in the evolution of the raccoon family

大美洲生物交流（英语：Great American Biotic Interchange）是一个重要的地理事件，通过巴拿马地峡的关闭将北美和南美的陆生动物群落连接起来。地质证据和化石记录表明，地峡的闭合发生在300万年前，但最近的研究表明，南北美洲之间的陆桥形成的年龄要大得多，大约1500万年。在北美洲起源的哺乳动物中，浣熊科（Procyonidae）也包括长鼻浣熊、金卡朱斯浣熊、长鼻浣熊和环尾浣熊，是南美洲历史最悠久的哺乳动物之一。化石记录显示，这群灭绝的成员是第一个移民到南美洲的北美哺乳动物，大约700 - 900万年。虽然流行的假设认为，现代成员的移民发生在300万年前，但最近基于DNA序列数据的估计显示，这个家庭在南美洲的时间要长得多。这项研究将更彻底地测试关于该组进化过程和时间的竞争假设，有可能修改我们对新热带哺乳动物进化的理解，同时有助于基因组学，系统学，分类学和地理学领域的进步，以及促进早期职业女性STEM研究人员的专业发展。本计画将使用一种综合的方法，以检验基于博物馆标本的基因组分析、形态计量学和生物地理学模型的相互竞争的假说。古DNA技术与高通量测序方法相结合，将被用来测序线粒体基因组，以及使用一种新的内含子捕获微阵列的核基因组样本。形态测量数据将分别进行分析，并结合比较基因组数据，以测试有关procyonid进化的假设，并修改这组的分类。一个新的浣熊家族进化的地理模型，容纳了最新的DNA和地质证据，将对传统的化石为基础的假设进行测试，并将整合系统发育数据，以重新评估与GABI相关的多样化的克里思和地理模式。将通过PI、Co-PI和合作者共同撰写的科学出版物分享结果。基因组和形态学数据，协议，脚本和分析中使用的参数将通过NCBI？基因库和树妖。

The Great American Biotic Interchange (GABI) was a major biogeographic event that connected the terrestrial animal communities of North and South America via the closure of the Panamanian Isthmus. Geological evidence and the fossil record have suggested that the closure of the isthmus occurred 3 million years ago (mya), but more recent studies suggest a much older age for the formation of a landbridge between North and South America, around 15 mya. Among mammals of North American origin, the raccoon family (Procyonidae), which also includes coatis, kinkajous, olingos, and ringtails, has one of the longest histories in South America. The fossil record shows that an extinct member of this group was the first North American mammal to immigrate to South America, approximately 7-9 mya. While the prevailing hypothesis states that immigration of modern members of this group took place 3 mya, recent estimates based on DNA sequence data revealed that this family has had a much longer tenure in South America. This study will more thoroughly test competing hypotheses regarding the process and timing of evolution of this group, with the potential to revise our understanding of mammal evolution in the Neotropics, while contributing to advancement in the fields of genomics, systematics, taxonomy, and biogeography, as well as promoting the professional development of an early-career female STEM researcher. This project will use an integrative approach to test competing hypotheses based on genomic analyses of museum specimens, morphometrics, and biogeographic modeling. Ancient DNA techniques in combination with high-throughput sequencing methods will be used to sequence mitochondrial genomes as well as to sample the nuclear genome using a novel intron-capture microarray. Morphometric data will be analyzed separately and in conjunction with comparative genomic data to test hypotheses regarding procyonid evolution and revise the taxonomy of this group. A new biogeographic model for the evolution of the raccoon family that accommodates the most recent DNA and geological evidence will be tested against the traditional fossil-based hypothesis, and will integrate phylogenetic data to reassess the tempo and geographic pattern of diversification associated with the GABI. Results will be shared through scientific publications co-authored by the PI, Co-PI, and collaborators. Genomic and morphological data, protocols, scripts and parameters used in the analyses will be made publicly available through the electronic repositories of NCBI?s Genbank and Dryad.