Dissertation Research: Biogeography and Phylogeny of Malesherbiaceae

小行星9623496 在俄亥俄州州立大学的顾问丹尼尔克劳福德的指导下，研究生卡拉·根格勒正在研究南美植物家族Malesherbiaceae，重点是从该家族的所有物种中获得新的DNA序列数据，以推断系统发育关系。 这一小科是南美洲太平洋沿岸沙漠地区特有的，分布在智利北方的阿塔卡马沙漠中。 它将作为研究该地区干旱植物和动物的地理分布和物种形成模式的起点。 目前的分类学分类是基于形态特征，其中大部分尚未进行变异性和可靠性评估。 重新评估这些和增加新的分子证据，从核核糖体基因测序将提供数据的物种之间的系统发育（系谱）的关系，并与相关群体的强有力的推论。 在秘鲁的实地工作将增加在智利已经收集的标本和从植物标本馆收集的标本。 反过来，物种发生学将为物种地理学（迁移路线、起源中心和多样化中心）和物种形成模式的研究提供必要的背景。 %%% 南美洲的太平洋沿岸沙漠包含了各种各样的干旱栖息地，据推测，这些栖息地自古新世以来随着安第斯山脉的上升和寒冷的洪堡海流在西部形成而发展起来。 更新世冰川作用被认为进一步影响了该地区的植物分布。 为了建立植物物种随时间移动的模式，必须建立许多群体的强大的遗传学。 这个项目承诺其中之一，为小家庭Malesher 'iaceae。 ***

9623496 Crawford Graduate student Karla Gengler, with direction from adviser Daniel Crawford at Ohio State University, is studying the South American plant family Malesherbiaceae, with an emphasis on obtaining new DNA sequence data from all the species in the family in order to infer phylogenetic relationships. This small family is endemic to the Pacific coastal desert region of South America, and occurs in two areas separated by the Atacama Desert in northern Chile. It will serve as a starting point for the study of biogeography and speciation patterns of aridland plants and animals of this region. The current taxonomic classification is based on morphological characters, most of which have not been evaluated for variability and reliability. Re-evaluation of these and addition of new molecular evidence from nuclear ribosomal gene sequencing will provide data for robust inferences of phylogenetic (genealogical) relationship among the species and with related groups. Field work in Peru will augment collections already made in Chile and those from herbarium holdings. In turn, the phylogeny will provide a necessary background for studies of biogeography (migration routes, centers of origin and of diversification) and of speciation patterns. %%% The Pacific coastal desert of South America contains a variety of arid habitats that are presumed to have developed since the Paleocene as the Andes mountains rose and the cold Humboldt Current formed to the west. Pleistocene glaciations are thought to have further affected plant distributions in this region. In order to establish patterns of plant species movements through time, robust phylogenies of many groups must be established. This project promises one of these, for the small family Malesher`iaceae. ***