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

贝米斯和希尔顿拥有超过24,000种活着的鱼类，包括超过一半的活着的脊椎动物。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，我们仍然缺乏关于硬骨动物解剖学的许多信息，对于硬骨动物的进化起源和多样性等基本问题也几乎没有达成共识。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，提出了一项由两部分组成的研究。首先，他将(第一次)详细描述两种北美硬骨鱼的骨骼，这些骨骼被称为月亮眼和金眼鱼(海龙属)，基于广泛的一系列标本，包括地理上的(以评估变异性)和个体发育(以评估从幼年到成年的发育变化)。月眼鱼和金眼鱼属于硬骨鱼的早期进化辐射，还包括刀鱼、象鼻鱼和龙鱼等熟悉的物种。这一群体被认为是在大约1.5亿年前从所有其他硬骨鱼中分离出来的，自那时以来，月亮眼和金眼鱼的骨骼基本保持不变。因此，在硬骨动物进化的研究中，它们可以用来代表早期的硬骨鱼。其次，学生将使用研究产生的新的解剖学信息对硬骨动物的系统发育进行广泛的分析。对30多种活的和化石的硬骨动物物种的骨骼特征的重点比较调查将建立在对研究中使用的标本的第一手观察的基础上。然后，可以将重建的硬骨动物进化多样化模式与包括分子系统学家在内的其他研究人员开发的模式进行比较。最终，可以综合鱼类的形态和分子数据，对现存硬骨鱼的起源和多样性做出可靠的解释。

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.