Dissertation Research: Ontogeny and Anatomy of the Skeleton in Mooneyes and Goldeyes and the Systematics of Hiodontiform Fishes

[00:73066]贝米斯和希尔顿Teleostei拥有超过24,000种活鱼，包括超过一半的活脊椎动物。如此巨大的多样性为进化生物学的发现提供了绝佳的机会。然而，我们对硬骨鱼的解剖学研究仍然缺乏足够的了解，对硬骨鱼的进化起源和多样性等基本问题也没有达成共识。为了解决这些问题，研究生埃里克·希尔顿在威廉·贝米斯博士的指导下，提出了一个分两部分的研究。首先，他将（第一次）详细描述两种北美硬骨鱼的骨骼，即月眼鱼和金眼鱼（Hiodon属），这两种硬骨鱼的骨骼是基于地理（评估变异）和个体发生（评估幼年到成年形态的发育变化）的广泛系列标本。月眼鱼和金眼鱼属于硬骨鱼的早期进化辐射，也包括一些熟悉的物种，如刀鱼、象鼻鱼和龙鱼。这个种群被认为是在大约1.5亿年前从所有其他硬骨鱼中分离出来的，从那时起，月眼鱼和金眼鱼的骨架基本保持不变。因此，在研究硬骨鱼的进化过程中，它们可以用来代表早期的硬骨鱼。其次，学生将使用由研究产生的新的解剖学信息对硬骨系统发育进行广泛的分析。在研究中使用的标本的第一手观察基础上，对30多种活的和化石的硬骨鱼物种的骨骼特征进行重点比较调查。重建的硬骨动物进化多样化模式可以与其他研究人员开发的模式进行比较，包括分子系统学家。最终，鱼类的形态和分子数据可以合成，从而对现存硬骨鱼的起源和多样性作出可靠的解释。

0073066Bemis and HiltonWith over 24,000 living fish species, Teleostei includes over half of all living vertebrate animals. Such a large diversity offers outstanding chances for discoveries in evolutionary biology. However, we still lack much information about teleostean anatomy and there is little consensus about such basic questions as the evolutionary origin and diversification of teleosts. To address these issues, graduate student Eric Hilton, under the direction of Dr. William Bemis, proposes a two-part study. First, he will describe in detail (for the first time) the skeletons of two North American teleosts known as mooneyes and goldeyes (genus Hiodon) on the basis of extensive series of specimens both geographic (to assess variability) and ontogenetic (to assess developmental changes from juvenile to adult form). The mooneyes and goldeyes belong to an early evolutionary radiation of teleosts that also contains such familiar species as knife fishes, elephant nose fishes, and arowanas. This group is believed to have split from all other teleosts approximately 150 million years ago, and the skeleton of mooneyes and goldeyes has remained largely unchanged since this time. For this reason, they can be used to represent early teleosts in studies of teleostean evolution. Second, the student will use the new anatomical information generated by the study for a broad analysis of teleostean phylogeny. A focused comparative survey of skeletal characteristics in more than thirty living and fossil teleostean species will build upon the first-hand observations of specimens used in the study. The reconstructed patterns of teleostean evolutionary diversification can then be compared with patterns developed by other researchers, including molecular systematists. Ultimately the morphological and molecular data on fishes can be synthesized to yield a reliable account of the origins and diversity of living teleosts.