CAREER: Phylogenetic scale-dependency of the patterns and processes of quantitative trait evolution

职业：数量性状进化模式和过程的系统发育规模依赖性

• 批准号: 2237613
• 负责人: Samantha Price
• 金额: $ 126.05万
• 依托单位: Clemson University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-15 至 2028-02-29
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2237613&HistoricalAwards=false
• 关键词: CAREER; Phylogenetic; scale; dependency; patterns

All life is linked by common ancestry, as revealed by genetic and physical similarities. This is depicted as a tree of life with a single root splitting into many branches, which further split into smaller branches and so on, forming nested groups of species known as clades. To understand the processes that generated the astounding diversity of life on earth, biologists and paleontologists conduct investigations at a variety of scales across this tree, comparing amongst clades of different taxonomic rank (e.g., Genus, Family, Order), size or age. Although rarely acknowledged, it is currently assumed that the conclusions identified at one scale can be applied to all other scales. However, this critical assumption is yet to be validated. This research will investigate how predictable results are across scales, using the highly diverse teleost fishes, which includes approximately half of all vertebrate species. The researchers will determine if patterns of fish body shape evolution are identical, random or vary systematically across scales. Establishing the predictability of these patterns, and processes inferred from them, will determine if and how conclusions drawn at one scale can be applied to another scale. This will have broad implications for synthesizing results across fields that work at different scales and in particular, the ability to connect studies on fossils and living organisms. This project will also improve access to undergraduate research opportunities, integrating students into the scientific discovery process through the development of a Classroom-based Undergraduate Research Experience, and publishing associated Open Educational Resources. This project will build an empirical understanding of how phylogenetic scale influences patterns and processes of quantitative trait evolution. To accomplish this objective the researchers will build upon their existing teleostean body shape dataset of approximately 16,000 specimens from 6,000 species. They will add measurements on a further 17,500 specimens from around 4,500 species to provide denser sampling within species and at shallower nodes in the phylogeny. Two complementary approaches to cross-scale analysis will be used to identify scale-dependency and its predictability. The first will apply mixed Gaussian phylogenetic models of quantitative trait evolution to the full phylogenetic extent to identify parameter shifts; the second will investigate patterns one scale at a time using more traditional phylogenetic comparative methods. Using four ways of delimiting scale: clade age, clade size, tree depth and taxonomic rank, the researchers will also quantify how patterns of scale-dependency are influenced by the method chosen to define scale. Simulations will be used to investigate the potential for statistical artifacts and the influence of methodological and data limitations. These analyses will determine whether phylogenetic scale-dependency is the exception or the rule. The project will also include training opportunities at the undergraduate, graduate student and postdoctoral levels.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.

所有的生命都是由共同的祖先联系在一起的，正如基因和身体上的相似性所揭示的那样。这被描述为一棵生命之树，一个单一的根分裂成许多分支，这些分支进一步分裂成更小的分支，以此类推，形成了被称为进化枝的嵌套物种群。为了了解产生地球上惊人的生命多样性的过程，生物学家和古生物学家在这棵树上进行了各种尺度的调查，比较了不同分类等级（例如，属、科、目）、大小或年龄的进化枝。虽然很少承认，但目前假定在一个比额表上确定的结论可以适用于所有其他比额表。然而，这一关键假设尚未得到证实。这项研究将利用高度多样化的硬骨鱼（包括大约一半的脊椎动物物种）来研究跨尺度的可预测结果。研究人员将确定鱼类体型进化的模式是相同的，随机的还是系统地在不同的鳞片上变化。建立这些模式的可预测性，以及由此推断出的过程，将决定在一个尺度上得出的结论是否以及如何适用于另一个尺度。这将对跨领域的综合结果产生广泛的影响，特别是将化石和生物体的研究联系起来的能力。该项目还将改善本科生的研究机会，通过开发基于课堂的本科生研究经验，将学生融入科学发现过程，并发布相关的开放教育资源。这个项目将建立一个关于系统发育规模如何影响数量性状进化的模式和过程的经验理解。为了实现这一目标，研究人员将建立在他们现有的来自6000个物种的大约16000个标本的骨骨体型数据集的基础上。他们将对来自大约4500个物种的17500个标本进行进一步的测量，以在物种内部和系统发育的较浅节点上提供更密集的采样。跨尺度分析的两种互补方法将用于确定尺度依赖性及其可预测性。首先，将数量性状进化的混合高斯系统发育模型应用到全系统发育程度，以识别参数转移；第二个将使用更传统的系统发育比较方法，一次研究一个尺度的模式。使用四种划分尺度的方法：进化枝年龄、进化枝大小、树深度和分类等级，研究人员还将量化尺度依赖模式如何受到所选择的定义尺度的方法的影响。模拟将用于调查统计伪影的可能性以及方法和数据限制的影响。这些分析将决定系统发育尺度依赖性是例外还是规律。该项目还将包括本科生、研究生和博士后的培训机会。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。