Systematics, Ontogeny, Osteology and Historical Biogeography of Fossil and Living Gars (Actinopterygii, Lepsosteiformes)

DEB-9707705 Grande 雀鳝加尔斯（Lepisosteidae）是一个非常长寿的组合，被大多数鱼类学家认为是最原始的生活群体Neopaltii（一个包含大约一半的脊椎动物物种的群体）。 这七种现存的雀鳝现在仅限于从加拿大东南部到古巴的美洲东部地区。 已灭绝的加尔斯，一些超过1亿年的历史，记录了加尔斯曾经广泛分布，出现在美洲大陆，欧洲，非洲，马达加斯加和印度。 L博士格兰德（芝加哥菲尔德博物馆）和W。Bemis（来自马萨诸塞州大学）将在所有现存的和众多灭绝加尔斯中进行第一次比较解剖学、地理学和生态学（包括古生态学）的综合研究。 他们的研究将以骨骼变异的彻底、详细的检查为基础，但他们也将检查活体材料的关键形态特征的以下发育阶段。 几个化石物种将被描述和物种水平的分类问题将得到解决。 一个解决的谱系（episosteid物种和原始neopterygian组）预计将产生关键的信息，围绕地球的历史，生物多样性和生物灭绝的模式的主要问题。 这项工作还将为解决鱼类学中的一个主要问题提供极其相关的数据：硬骨鱼的起源。

DEB-9707705 Grande The gars (Lepisosteidae) are members of a very long-lived assemblage that is thought by most ichthyologists to be the most primitive living group of Neopterygii (a group that contains about half of all species of vertebrate animals). The seven, living species of gars are today restricted to the eastern-America region, from southeastern Canada to Cuba. Extinct species of gars, some over 100 millions years old, document that gars were once widespread, occurring on both American continents, Europe, Africa, Madagascar, and India. Drs. L. Grande (of the Field Museum in Chicago) and W. Bemis (of the University of Massachusetts) will carry out the first comprehensive study of comparative anatomy, biogeography, and ecology (including paleoecology) among all living and numerous extinct species of gars. Their study will be anchored in thorough, detailed examination of skeletal variation but they also will examine living material to following developmental stages of critical morphological characters. Several fossil species will be described and species-level taxonomic problems will be resolved. A resolved genealogy (phylogeny) of lepisosteid species and of primitive neopterygian groups is expected to yield critical information regarding major questions surrounding the Earth's history, biodiversity, and patterns of biological extinction. The work also will provide extremely relevant data towards resolution of one of the major questions in ichthyology: the origin of teleost fishes.