Molecular Systematics of Lamniform Sharks Using Creatine Kinase Genes

在现存的16种鲨鱼中，有臭名昭著的（大白鲨）和巨大的（姥鲨）。尽管人们对这些鱼类的形态和分子生物学以及大约1.4亿年前出现的化石进行了研究，但板状鲨鱼的系统发育关系，以及物种在形态、解剖、生理和栖息地方面的极端多样性的起源，还没有得到很好的理解。在这项研究中，安德鲁·马丁将评估这些鲨鱼之间的系统发育关系。他将从肌酸激酶基因家族的核基因中获得分子序列信息，并利用这些序列构建系统发育树。然后将这些树与由其他形态学和分子信息构建的树进行比较。来自所有这些来源的数据将试图回答有关板形鲨历史的问题；例如，在这些鱼类中，吃浮游生物（相对于更大的猎物）的能力是否出现过一次，或者不止一次。这项研究还将帮助科学家了解基因在一组生物体的历史中是如何变化的，以及这些变化如何与生物体的形状或行为在很长一段时间内的变化有关。

9628094 MARTIN Lamniform sharks include infamous (Great White Shark) and spectacularly large (Basking Shark) forms among their sixteen living species. Despite work that has been done on the morphology and molecular biology of these fish, and fossils that appear beginning approximately 140 million years ago, the phylogenetic relationships of lamniform sharks, and therefore the origins of the extreme diversity among species in morphology, anatomy, physiology and habitat, are not well understood. In this study, Andrew Martin will evaluate the phylogenetic relationships among these sharks. He will obtain molecular sequence information from nuclear genes in the creatine kinase gene family, and use these sequences to construct phylogenetic trees. These trees will then be compared with trees constructed from other morphological and molecular information. Data from all these sources will attempt to answer questions about lamniform shark history; for example, whether the ability to eat plankton (as opposed to larger prey) arose once, or more than once, among these fish. The study should also help scientists understand how genes change during the history of a group of organisms, and how these changes may be related to changes in an organism's shape or behavior over long periods of time.