An investigation of Peramorphosis in isorophinid edrioasteroid echinoderms

异棘皮类小行星棘皮动物的超形态研究

• 批准号: 0745918
• 负责人: Colin Sumrall
• 金额: $ 13.77万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-15 至 2013-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0745918&HistoricalAwards=false
• 关键词: investigation; Peramorphosis; isorophinid; edrioasteroid; echinoderms

Investigating the Role of Heterochrony in the Evolution of EdrioasteroidsColin Sumrall, University of Tennessee, KnoxvilleEAR-0745918Heterochrony, evolution by changing the timing of morphological change during ontogeny, is an important evolutionary mechanism throughout the Phanerozoic. In most clades, paedomorphosis (adult descendents having characteristics of the ancestral juvenile) is commonly cited as the dominant pattern. In isorophids, however, peramorphosis (adult descendants with characteristics that are overdeveloped with respect to their ancestors) is the dominant pattern in the ambulacral feeding apparatus. This two-year project aims to collect and interpret phylogenetic, and ontogenetic, data for isorophid edrioasteroids and use these data to investigate the different ways in which isorophid edrioasteroids are specializing via heterochrony. Phylogeny will be reconstructed using maximum parsimony on a genus level data matrix for all isorophid edrioasteroids. Ontogeny will be studied using elemental fate mapping and allometric studies of growth. These two areas will be combined to investigate portions of the phylogenetic history of isorophids where heterochrony played an important role and determine if different styles of heterochrony are dominant during the recovery from two mass extinctions (end Ordovician and Frasnian/Famennian). This project will involve graduate and undergraduate students directly into interdisciplinary research where they will learn new techniques. Minority undergraduate students will be included by collaboration with the NSF-funded East Tennessee Geosciences Program. Results will be incorporated into a web-based activity on organic evolution via heterochrony and middle school education modules on evolution for use in east Tennessee classrooms.

调查异时性在Edrioasteroids演化中的作用Colin Sumrall，田纳西大学，Knoxville-0745918异时性，通过改变个体发育期间形态变化的时间来进行演化，是贯穿整个中生代的重要演化机制。在大多数分支中，幼态（paedomorphosis）（成年后代具有祖先幼态的特征）通常被认为是优势模式。 然而，在等蛇目中，peramorphosis（成年后代具有相对于其祖先过度发育的特征）是步带摄食器的主要模式。这个为期两年的项目旨在收集和解释系统发育和个体发育的数据，为isorophid edrioasteroids和使用这些数据来调查isorophid edrioasteroids通过异时性专业化的不同方式。 系统发育将重建所有isorophid edrioasteroids的属级数据矩阵上使用最大简约。 将使用元素命运绘图和生长的异速生长研究来研究个体发育。 这两个领域将结合起来，调查异时性发挥了重要作用的isorophids的系统发育史的一部分，并确定不同风格的异时性是占主导地位的两个大规模扩张（奥陶纪末和弗拉斯/法门）的恢复过程中。 该项目将涉及研究生和本科生直接进入跨学科研究，他们将学习新技术。 少数民族本科生将与NSF资助的东田纳西州地球科学计划合作。 研究结果将纳入一个基于网络的活动，通过异时性和中学教育模块的进化有机进化，在东田纳西州的教室使用。