Understanding the diversity of life: trait correlations from micro- to macroevolutionary scales

项目简介：了解导致长期生物多样性的机制是进化生物学最重要的基础之一。然而，当我们观察生命的巨大多样性时，我们可以看到几个令人惊讶的明显模式。多样性并不均匀地分布在生命之树上。这表明，产生多样性的过程是受限制的：一些谱系经历了与其他谱系不同的特征进化和多样化速度，物种的数量及其形式和功能的多样性也受到限制。这清楚地表明了遗传、生态、发育或生理上对进化的限制。这些限制可能是特定于分类单元的，也可能是跨分类单元的，建议在更高的分类水平上进行一般限制。解决驱动这些模式的机制将极大地提高我们对决定生命多样性的过程的理解。PHD的总体目标是测试特征之间的相关性如何在多个尺度上(种内、内和交叉)进化，以塑造整个生命树上的特征和物种的多样性。具体地说，第一个目标是测试特质相关性随时间的稳定性。表型性状相关性的稳定性可能会产生重要的宏观进化结果，例如通过限制支系内部和支系之间潜在的总表型多样性(即它们的差异)。第二个目标是测试相关性的变化如何限制(I)不同谱系之间的物种差异和(Ii)物种的多样性。

Project description : Understanding the mechanisms that lead to biological diversity over long periods of time is one of the most important underpinnings of evolutionary biology. However, when we look at the immense diversity of life we can see several clear patterns that are surprising. Diversity is not evenly distributed across the tree of life. This suggests that the processes generating diversity are constrained: some lineages experience different rates of trait evolution and diversification than others and there are constraints on the numbers of species and on their variety of form and function. This clearly suggests genetic, ecological, developmental, or physiological limits on evolution. These constraints may be taxon specific or cut across taxa, suggesting general limits at higher taxonomic levels. Resolving the mechanisms driving these patterns will dramatically improve our understanding of the processes that determine the diversity of life.The overall objective of the PhD is to test how correlations among traits evolve at multiple scales (intraspecific, intraclade and interclade) to shape the diversity of traits and species across the tree of life. Specifically, the first objective is to test the stability of trait correlations through time. The stability of phenotypic trait correlations may have important macroevolutionary consequences, for example by constraining the potential total phenotypic diversity within and among clades (i.e. their disparity). The second objective is to test how variation in correlations constrains (i) disparity and (ii) diversity of species among lineages.