Uncovering the evolutionary history and significance of Fibonacci spirals in vascular plants

描述地质时期生物形态的驱动因素仍然是进化生物学的重大挑战之一。然而，这样做被证明是困难的，因为很少有研究系统可以测试选择、约束和机会的竞争作用。陆生植物为解决这些问题提供了一个很大程度上被忽视但却是理想的研究系统，因为它们有出色的化石记录，并且在形态、功能和发育之间有着密切的关系。在《为什么fib》中，我将利用所有这些优势来揭示陆地植物的一个关键特征——叶子的排列——背后的进化驱动因素。从理论上讲，植物的叶子可以以几乎无限种可能的排列方式排列在茎上。然而，事实并非如此。事实上，它们以非常有限的离散模式排列，其中最常见的是用斐波那契数列的整数描述的螺旋。为什么斐波那契螺旋在植物中如此频繁，这个问题困扰了科学家几个世纪，至今仍是一个未解之谜。在《为什么fib》一书中，我将以自己的跨学科背景和实验室开发的突破性新方法为基础，采用一种广泛的进化方法来回答这个问题。为了揭示斐波那契螺旋的进化史，我将结合从研究非种子植物的发展中获得的结果，从新收集的化石中获得的见解，对定量性状进化的分析和定量建模方法。然后，我将使用这些数据，代表超过4亿年的进化，来测试斐波那契螺旋流行的主要竞争假设。这个项目的结果将为生物形态在地质时期的驱动因素提供一个教科书式的案例研究，同时让我解决为什么斐波那契螺旋在今天的植物中如此普遍的谜团。

Characterising the drivers of biological form over geological time continues to represent one of the grand challenges in evolutionarybiology. However, doing so has proved difficult as there are few study systems where it is possible to test the competing roles ofselection, constraint and chance. Land plants offer a largely overlooked but ideal study system for tackling these questions because oftheir excellent fossil record and close relationship between form, function and development. In WhyFib I will leverage all of thesebenefits to uncover the evolutionary drivers behind one of the key features of land plants, the arrangement of leaves.On theoretical grounds, plant leaves could be positioned on stems in an almost infinite number of possible arrangements. However,they are not. In fact, they are arranged in a very restricted number of discrete patterns, of which by far the most frequent are spiralsthat are described by integers of the Fibonacci series. Why Fibonacci spirals are so frequent in plants has perplexed scientists forcenturies and remains a major unanswered question.In WhyFib I will answer this question by taking a broad evolutionary approach, underpinned by my own interdisciplinary backgroundand new break-through methodologies developed in my lab. To uncover the evolutionary history of Fibonacci spirals I will combineresults gained from investigating development in non-seed plants with insights from newly collected fossils, analyses of quantitativetrait evolution and quantitative modelling approaches. I will then use these data, representing over 400 million years of evolution, totest the major competing hypotheses for the prevalence of Fibonacci spirals.The results of the project will provide a textbook case study for the drivers of biological form over geological time, while allowing meto solve the mystery of why Fibonacci spirals are so common in plants today.