DISSERTATION RESEARCH: Integrating Biogeography, Cytology, Niche Modeling and Phylogenetics to Understand the Evolutionary History of Endemic Campanula Species in the Mediterranean

物种多样性的准确界定和估计是生物学许多领域的关键方面，包括地理学，生态学和保护。这项研究的重点是提高我们对地中海盆地物种多样性的理解-世界上生物多样性最丰富的地区之一。随着主要由于气候变化和人类压力对生物多样性的威胁不断增加，准确的评估对保护工作越来越重要。为了研究精细尺度的进化和地理模式和过程，研究人员确定了一组知之甚少的风铃草（风铃草物种复合体），可以作为理解这一高度多样性地区进化驱动因素的模型。该项目将特别侧重于推断进化历史，并提供这组植物物种多样性的准确评估。结果将有重要的影响，了解地中海生物多样性的起源，设计成功的保护工作，并预测可能的应对未来气候变化。研究人员将采用下一代测序方法，涉及有针对性的丰富的许多核基因座的人口都广泛的风铃草erinus和狭窄的地方性，风铃草creutzburnus。虽然测序将集中在风铃草物种复合体上，但核探针组将被设计为使其在风铃草科（超过2400个分类群）中有用。这种有针对性的测序技术，结合形态学数据，以及最近的结合和基于模型的方法，将作为未来研究的模型，整合传统的系统和基因组水平的数据，用于评估物种边界和检测隐蔽的物种形成维管植物。在这项研究过程中开发的探针集将提供给科学界，促进家庭内未来的进化研究。在系统发育和地理学框架中研究风铃草复合体将阐明物种多样化和持久性的驱动因素，并使研究人员能够将这些机制与生态，地质历史和气候波动等因素联系起来。三个假设将测试关于这些分类群：i）隐藏的分类多样性是目前在风铃草erinus聚集; ii）历史的海平面的变化有助于异域物种形成; iii）多倍体（基因组复制）一直是一个重要的历史因素，在这个组和多倍体可能代表物种不同于他们的二倍体祖先。对这些进化过程的理解在这个生物多样性热点地区尤为重要，预计保护工作将是最具挑战性的，但可能会带来最高的回报。

Accurate delimitations and estimates of species diversity are critical aspects for many areas of biology, including biogeography, ecology, and conservation. This research focuses on improving our understanding of species diversity in the Mediterranean Basin - one of the most biologically diverse areas in the world. As threats to biodiversity mount, due mainly to climate change and human pressure, accurate assessments are increasingly important for conservation efforts. To study fine-scale evolution and biogeographic patterns and processes, the researchers have identified a poorly understood group of bellflowers (the Campanula erinus species complex) that can serve as a model for understanding the drivers of evolution in this highly diverse area. This project will focus specifically on inferring the evolutionary history and providing an accurate assessment of species diversity in this group of plants. Results will have important implications for understanding the origins of Mediterranean biodiversity, designing successful conservation efforts, and anticipating possible responses to future climate change.The researchers will employ a next-generation sequencing approach, involving targeted enrichment of numerous nuclear loci across populations of both the widespread Campanula erinus and the narrow endemic, Campanula creutzburgii. Though sequencing will focus on the Campanula erinus species complex, the nuclear probe set will be designed such that it will be useful across the Campanulaceae (more than 2400 taxa). This targeted sequencing technique, in conjunction with morphological data, and recent coalescent and model-based methods, will serve as a model for future studies integrating traditional systematic and genome-level data for evaluating species boundaries and detecting cryptic speciation in vascular plants. The probe set developed during the course of this study will be made available to the scientific community, facilitating future evolutionary studies within the family. Studying the Campanula erinus complex in a phylogenetic and biogeographic framework will illuminate the drivers of diversification and persistence of species and allow the researchers to relate these mechanisms to factors such as ecology, geologic history, and climatic fluctuations. Three hypotheses will be tested regarding these taxa: i) Cryptic taxonomic diversity is present within the Campanula erinus aggregate; ii) Historical sea level changes contributed to allopatric speciation; iii) Polyploidy (genome duplication) has been an important historical factor in this group and polyploids may represent species distinct from their diploid progenitors. An understanding of these evolutionary processes will be especially critical in this biodiversity hotspot, where conservation efforts are expected to be most challenging but likely give the highest payoff.