Collaborative Research: Temperate radiations and tropical dominance: the diversification and evolution of the plant clade Ericales

与向两极延伸的温带相比，环绕地球赤道地带的热带森林是更多植物物种的家园。几个世纪以来，生物学家一直试图解释热带和温带地区生物多样性的差异，但有限的数据阻碍了这一努力，特别是在植物群中。然而，了解这些世界范围内的模式对于了解美国自然系统中的这些模式是至关重要的，因为在美国，植物在生态和经济方面发挥着关键作用。这项研究将提供一个多样化的和全球分布的植物组的详细研究，被称为Ericales，其中包括各种重要的经济物种，如蓝莓，猕猴桃，柿，巴西坚果，木材(如乌木)，杜鹃花，杜鹃，甚至食肉植物。这些新收集的大数据资源将使研究人员能够发现有助于地球森林生物多样性的起源和维持的遗传和形态因素。这项研究还将促进培训下一代年轻的STEM研究人员，使他们能够熟练地应用计算和植物基因组学资源来应对国家面临的挑战。热带植物惊人的多样性导致了物种丰富度向低纬度增加的纬度多样性梯度；这种模式在整个生命树上都可以找到。尽管热带生物群的重要性以及跨越、进出热带纬度的进化/生态重要性，但物种DNA序列和形态特征的稀少样本阻碍了在解决温带和热带过渡谱系的起源、多样性和生态位进化方面的重大进化问题的进展。这项研究的定位是克服这些限制，使用多样性和生态重要的植物分支杜鹃花作为案例研究。研究人员将使用转录组和靶标捕获测序来解决系统发育关系，并以前所未有的规模描述Ericales中的基因和基因组进化，以结合古植物学数据、形态特征(包括习性和花卉)以及关于物种生态位的信息来生成强大的物种水平的系统发育图，以评估热带和温带多样性的内在和外部关联。他们将进行分析，解决人们普遍感兴趣的具体问题：1)温带和热带谱系之间多样化和进化的主要驱动力是什么？2)适应新环境是否会导致分子进化和多样化的速度更快？3)不同生物群和不同海拔的谱系之间进化速度的差异是否反映在个别物种的地理和生态位进化模式中？4)高度多样化和受到威胁的热带山地生物群背后有哪些生物地理历史和适应？这一裁决反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The tropical forests that circle the equatorial belt of Earth are home to vastly more plant species than the temperate zones that extend toward the poles. Biologists have tried to explain the difference in biodiversity between tropical and temperate regions for centuries, but efforts have been hindered by limited data, particularly among plant groups. Nevertheless, understanding these worldwide patterns is fundamentally important to understanding these patterns in natural systems in the U.S., where plants play a key ecological and economic role. This research will provide a detailed study of a diverse and globally distributed group of plants, known as the Ericales, that includes a variety of economically important species such as blueberries, kiwi fruit, persimmon, Brazil nut, timber woods (e.g., ebony), azaleas, rhododendrons, and even carnivorous plants. These newly collected "big data" resources will allow researchers to discover genetic and morphological factors that contribute to the origin and maintenance of the biological diversity in Earth's forests. This research will also promote the training of the next generation of young STEM researchers to be fluent in application of computational and plant genomics resources to challenges facing the nation.The staggering diversity of tropical plants contributes to a latitudinal diversity gradient of increased species richness towards lower latitudes; a pattern found across the tree of life. Despite the significance of tropical biomes and the evolutionary/ecological importance of movements across, into, and out of tropical latitudes, the sparse sampling of species for both DNA sequences and morphological traits has inhibited progress in addressing major evolutionary questions regarding the origin, diversification, and niche evolution of lineages with temperate and tropical transitions. This research is positioned to overcome these limitations, using the diverse and ecologically important plant clade Ericales as a case study. The researchers will use transcriptome and targeted-capture sequencing to resolve phylogenetic relationships and characterize gene and genome evolution within the Ericales at an unprecedented scale to produce a robust species-level phylogeny combined with paleobotanical data, morphological traits (including habit and floral), and information regarding species niche to evaluate the intrinsic and extrinsic correlates of tropical and temperate diversification. They will conduct analyses that address specific questions of broad interest: 1) What are the major drivers of diversification and evolution between the temperate and tropical lineages? 2) Do adaptations to new environments lead to faster rates of both molecular evolution and diversification? 3) Are differences in rates of evolution between lineages in different biomes and different elevations reflected in individual species geographic and niche evolution patterns? 4) What biogeographic histories and adaptations underlie the highly diverse and threatened tropical montane biomes?This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.