Dissertation Research: The Macroevolutionary Consequences of a Neogastropod Adaptation

论文研究：新腹足动物适应的宏观进化后果

• 批准号: 0073248
• 负责人: David Jablonski
• 金额: $ 1万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2003-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0073248&HistoricalAwards=false
• 关键词: Dissertation; Research; Macroevolutionary; Consequences; Neogastropod

0073248Jablonski and PriceAlthough evolutionary biologists have formalized the study of adaptation, few studies explain both why a trait is adaptive and ho--w it affects a lineage's history. Graduate student Rebecca Price, assisted by her adviser Dr. David Jablonski, addresses this issue in a study of fossil and living species of a group of gastropod molluscs of the Fasciolariidae. The neogastropods are an ideal focal taxon because they have high modern diversity, permitting the use of living animals to determine the functional significance of the character in question, and a rich fossil record directly to observe morphological changes through geologic time. The hypotheses under test concern the columellar folds, or plications on a gastropod shell's aperture, that traditionally are used as taxonomic characters, and that may function as adaptations, for example in body retraction to avoid predators, or in muscle attachment to increase speed of movement. Such functional adaptations may have affected rates and patterns of species diversification in different sublineages within the Fasciolariidae (Neogastropoda: Mollusca). This family has a rich fossil record, a range of fold morphologies, and, according to a preliminary phylogeny, has lost and added folds repeatedly. The student will use computed tomography (facilities made available at Argonne National Laboratory outside Chicago) to depict in 3-dimensions and quantify a series of characters that describe columellar fold morphology in ca. 100 samples in this family. To test that columellar folds are adaptive, and to evaluate some hypothetical functions, the student will (1) map each aspect of fold morphology onto an evolutionary tree to determine when it evolved, and (2) conduct a series of functional experiments at a marine station on shells with and without folds. The experiments are designed to improve our understanding of correlations between morphology and function, with the results extrapolated back on the phylogeny to track the 130 million years of fasciolariid history in functional terms.

0073248Jablonski和Pricealthough进化生物学家已经正式化了适应的研究，很少有研究可以解释为什么特征是适应性的，又是HO-W-它会影响血统的历史。 在顾问David Jablonski博士的协助下，研究生Rebecca Price在研究了Fasciolariidae的一组腹足动物软体动物的化石和活物种中解决了这个问题。 Neogastropods是理想的焦点分类单元，因为它们具有较高的现代多样性，允许使用活动物来确定所讨论的角色的功能意义，并直接获得丰富的化石记录，以通过地质时间观察形态变化。 所测试的假设涉及柱状折叠，或在腹足动物壳的光圈上的折叠，传统上用作分类特征，并且可能起适应性的作用，例如在身体缩回中以避免捕食者或肌肉依恋以增加运动速度。这种功能适应可能影响了fasciolariidae（neogastropoda：Mollusca）中不同sublineages中物种多样化的速率和模式。 这个家族具有丰富的化石记录，一系列折叠形态，根据初步的系统发育，已反复丢失并添加倍数。 该学生将使用计算机断层扫描（芝加哥以外的Argonne国家实验室提供的设施）来描绘3维，并量化一系列描述CA中的Columellar折叠形态的角色。这个家庭中有100个样本。 为了测试Columellar褶皱是适应性的，并且为了评估一些假设的功能，学生将（1）将折叠形态的每个方面映射到进化树上以确定其何时进化，并且（2）在带有和无折叠的壳上的炮弹上进行一系列功能实验。 该实验旨在提高我们对形态和功能之间相关性的理解，结果反过来又回到了系统发育中，以功能性的术语跟踪1.3亿年的cassiolariid历史记录。