Character evolution in pleurocarpous mosses: a phylogenetic study focusing on the Lembophyllaceae/Neckeraceae - clade

侧生藓类植物的形态多样性及其近期的快速辐射是苔藓植物学中最具挑战性的问题之一。由于目前的概念的字符进化在很大程度上是误导，彻底的系统发育分析相结合的分子和形态学数据是必要的，了解侧果藓类的进化至关重要。在这项研究中，我们将集中在两个密切相关的家庭，Lembophyllaceae和Neckeraceae。本研究的目的是：（1）利用形态学和DNA序列数据重建支持性较好的科的亲缘关系;（2）确定侧果内Neckeraceae/Lembophyllaceae的祖先分支;（3）研究侧果内形态特征的演化。系统发育分析将包括最先进的方法，如最大似然法、贝叶斯推断法以及基于简约法的方法。系统发育分析将a）在DNA/RNA二级结构计算和分子模式分析的指导下，对手动比对的序列数据进行，和B）应用直接优化一种新的基于简约的算法。深入的分析将提供新的见解的模式和速度的分子进化的侧果，提出了一个新的系统发育的概念，研究组和确定形态的synapomorphies。我们将澄清，如果目前使用的诊断形态特征的演变是一个独立的适应性进化的结果，特别是附生栖息地，发生了几次独立的采样谱系，也许在pleuocarpous苔藓一般。

The morphological diversity of epiphytic pleurocarpous mosses and their recent rapid radiation is one of the most challenging problems in bryology. As current concepts of character evolution are largely misleading, thorough phylogenetic analyses combining molecular and morphological data are needed and crucial for understanding the evolution of pleurocarpous mosses. In this study we will focus on two closely related families, Lembophyllaceae and Neckeraceae. Aims of this study are: 1) to reconstruct well supported phylogenies of the families using both morphological and DNA sequence data 2) to pinpoint the ancestral clades of the Neckeraceae/Lembophyllaceae within pleurocarps, and 3) to study the evolution of morphological characters within this group. The phylogenetic analyses will comprise state of the art approaches such as maximum likelihood, Bayesian inference as well as parsimony-based methods. Phylogenetic analyses will be performed a) on manually aligned sequence data, guided by DNA/RNA secondary structure calculations and analyses of molecular patterns, and b) applying direct optimization a novel parsimony-based algorithm. The thorough analyses will provide new insights into the modes and rates of molecular evolution in pleurocarps, present a new phylogenetic concept of the study group and identify morphological synapomorphies. We will clarify if the evolution of the currently used diagnostic morphological traits is a result of an independent adaptive evolution, especially to epiphytic habitats that occurred several times independently in the sampled lineages and perhaps in pleuocarpous mosses in general.