Role of palaeogeographical and ecological factors on the evolution and assembly of plant communities

我整合了生物地理学、系统发生学、地质学和生态学的领域，以了解岛屿系统上生物群的起源和组装。这项工作有助于减轻生物多样性的损失。我的长期研究计划旨在解释历史事件和当前的生态因素如何影响热带和北部地区植物物种的进化和分布。利用案例研究和综合公开可用的信息，我的研究小组有三个相互关联的短期目标：1)阐明加勒比海植物的历史生物地理；2)研究安第斯山脉季节性干旱森林的形成；3)推断北部岛屿上植物群落的潜在组装过程。加勒比海是世界上五大生物多样性热点地区之一，因此研究和保护加勒比海非常重要。我们将研究三个假说的作用：殖民、岛状物种形成和替代对加勒比海植物区系起源的影响。利用已发表的过时系统发育树，我们将推断植物的祖先区域，以测试加勒比地质历史对植物殖民或更替的影响的预测。我们还将从这些系统发育中估计殖民率和物种形成率。DNA测序将用于重建哥白尼属的系统发育树和生物地理史，作为案例研究，哥白尼属是加勒比海地区辐射的21种棕榈树物种。多达三分之一的全球人口生活在干燥的热带地区，这是热带地区最濒危的生态系统之一。目标2将为SDTF的形成提供一个空间和时间框架，这将补充安第斯形成的不完整地质证据。利用DNA测序，我们将对哥伦比亚安第斯山脉六个地点的两个仙人掌科SDTF物种进行系统地理和历史人口统计分析。系统发育群落生态学领域的诞生表明，群落中物种之间的系统发育距离可以指示推动群落聚集的是非生物、生物还是随机因素。我们将测试在北部岛屿上做出这些推论所需的两个条件。利用纽芬兰的六个栖息地，我们将首先在逐个谱系的基础上评估物种的系统发育距离是窄还是宽。其次，我们将测试对这些栖息地的特征适应是否具有进化保守性。我的研究计划将利用热带和北部地区历史和当前的生态观点，为岛屿生物地理学领域做出贡献。它将补充旨在重建加勒比群岛和安第斯隆起的起始、持续时间和空间背景的地质证据。我的长期研究将为保护区的设计和严重干扰地区的恢复提供信息，从而影响热带和北方生态系统的保护。三名博士、两名硕士和五名本科生将接受培训。

I integrate the fields of biogeography, phylogenetics, geology, and ecology to understand the origin and assembly of biota on island systems. This work can help mitigate biodiversity loss. My long-term research program aims to explain how historical events and current ecological factors have influenced the evolution and distribution of plant species in tropical and boreal regions. Using case studies and synthesizing publicly available information my research group has three inter-related short-term objectives: 1) elucidate the historical biogeography of Caribbean plants; 2) study the formation of seasonally dry forests (SDTF) in the Andes; and 3) infer the potential assembly processes of plant communities on a boreal island. The Caribbean is important to study and conserve because it is one of the world's top five biodiversity hotspots. We will investigate the role of three hypotheses: colonization, insular speciation, and vicariance on the origin of Caribbean flora. Using published dated phylogenetic trees, we will infer ancestral areas of plants to test predictions of the effects of Caribbean geological history on the colonization or vicariance of plants. We will also estimate colonization and speciation rates from these phylogenies. DNA sequencing will be used to reconstruct the phylogenetic tree and biogeographic history of Copernicia, a Caribbean radiation of 21 palm species, as a case study. Up to a third of the global population live in dry tropical areas, which are some of the most endangered ecosystems in the tropics. Objective 2 will provide a spatial and temporal framework for SDTF formation, which will complement the incomplete geological evidence of Andean formation. Using DNA sequencing, we will conduct a phylogeographic and historical demographic analysis of two SDTF species in the cactus family at six localities in the Colombian Andes. The field of phylogenetic community ecology was born with the suggestion that the phylogenetic distances separating species in a community, could indicate whether abiotic, biotic or random factors drive the community assembly. We will test two conditions needed to make these inferences on a boreal island. Using six habitats in Newfoundland we will first evaluate if the phylogenetic distances of species are narrow or wide on a lineage-by-lineage basis. Second, we will test if trait adaptations to these habitats are evolutionary conserved or not. My research program will contribute to the field of island biogeography using a historical and current ecological perspective in the tropics and boreal. It will complement geological evidence aimed at reconstructing the onset, duration and spatial context of the Caribbean archipelago and the Andean uplift. My long-term research will impact the conservation of tropical and boreal ecosystems by informing the design of protected areas and the restoration of heavily disturbed areas. Three PhDs, two MSc, and five undergraduate students will be trained.