Dissertation Research: Hybridization between the Western Gull (Larus occidentalis) and the Glaucous-winged Gull (L. glaucescens)

论文研究：西部海鸥（Larus occidentalis）和灰翅鸥（L. glaucescens）之间的杂交

• 批准号: 8901328
• 负责人: Ned Johnson
• 金额: $ 1.01万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-06-01 至 1991-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8901328&HistoricalAwards=false
• 关键词: Dissertation; Research; Hybridization; between; Western

Douglas Bell, a doctoral student working under the direction of Dr. Ned Johnson at the University of California..Berkeley, is working on an ambitious study of geographic variation in the Western and Glaucous.winged Gulls and a hybrid zone between the two. The Western Gull is an important coastal species ranging from the Baja Peninsula north along the Pacific coast to southern Washington where it gives way to the Glaucous.winged Gull which ranges northward to the western most Aleutian Islands; the hybrid populations occur from northern Oregon through Washington. Although hybridization among gull species (genus >Larus>) is often cited as an example of the process of species formation, the actual extent, nature and origin of hybridization among the gulls is poorly known. Bell proposes to address three conceptual foci: 1) geographical variation in the parental species, 2) the type of hybrid zone (is the hybrid zone stable, are hybrids selected against, are hybrids favored by selection in an ecologically intermediate area of overlap?), and 3) the origin of the hybrid zone in a historical context. The study will involve field work to collect specimens, to collect data on reproductive success in hybrid and non.hybrid pairings, on assortative mating and on vocalizations, and to make field observations on behavior. Characterizations of geographic variation will be made on hybrid index scores based on plumage color variation and other "soft" part color variation (iris color, leg color, etc.), on statistical analysis of skeletal measurements and at the molecular level. The study of species that are so closely related that they still hybridize (albeit on a limited basis) provide opportunities for dissecting the genetics and evolutionary processes that lead to the origin of species.

道格拉斯贝尔，一个博士生在指导下工作， 加州大学的Ned约翰逊博士伯克利群岛 致力于一项雄心勃勃的研究， 西部海鸥和蓝灰色海鸥。有翼海鸥和西部海鸥和蓝灰色海鸥之间的混合区 两个. 西鸥是一种重要的沿海物种， 从巴哈半岛向北沿着太平洋海岸到南部 华盛顿，在那里，它让位给了一只灰绿色的有翼海鸥， 向北延伸到阿留申群岛的最西部; 种群分布于从北方的俄勒冈州到华盛顿。 虽然海鸥物种（属>Larus>）之间的杂交往往是 作为物种形成过程的一个例子， 海鸥杂交的实际程度、性质和起源 鲜为人知。 贝尔提出解决三个概念焦点： 1)亲本种的地理变异，2） 杂交区（杂交区是否稳定，是否选择杂交种 相反，在生态环境中， 中间重叠区域？），杂种的起源 在历史背景下。 这项研究将涉及实地工作 收集标本，收集繁殖成功的数据， 杂交和非杂交配对，选择性交配和 发声，并对行为进行实地观察。 将对杂种进行地理变异的表征 基于羽毛颜色变化和其他“软”的指数得分 部分颜色变化（虹膜颜色、腿部颜色等），对 骨骼测量的统计分析， 分子水平。 对物种的研究， 有关他们仍然杂交（尽管在有限的基础上） 提供了解剖遗传学的机会， 导致物种起源的进化过程。