Dissertation Research: A Nutritional Basis for Insular Gigantism in Small Mammalian Herbivores

论文研究：小型食草哺乳动物岛状巨人症的营养基础

• 批准号: 8815175
• 负责人: Richard Lenski
• 金额: $ 0.9万
• 依托单位: University of California-Irvine
• 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: 1989-02-01 至 1992-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8815175&HistoricalAwards=false
• 关键词: Dissertation; Research; Nutritional; Basis; Insular

Body size influences the physiology, behavior and community level interactions of organisms, but little is actually known about the factors controlling it. Small mammalian herbivores, isolated on islands and relieved of predation and competition pressures, offer an ideal situation for the study of selection on size. Island herbivores subsist on a food supply which is not only less diverse, but less abundant than in mainland habitats. Theory predicts that larger animals will have lower specific metabolic rates, yet their gut size increases approximately isometrically. Thus, selection on body size may result from the greater efficiency of larger animals in extracting energy from low-quality foods. A comparative approach will be used to test this hypothesis. Selection on size will be measured on two islands--one where gigantism is exhibited, one where it is not. Dietary composition and quality will be measured and analyzed, then related to biological traits associated with size.

体型影响生物体的生理、行为和群落水平的相互作用，但实际上人们对控制它的因素知之甚少。 小型哺乳动物食草动物与世隔绝，摆脱了捕食和竞争的压力，为研究体型选择提供了理想的环境。 岛屿食草动物赖以生存的食物供应不仅比大陆栖息地的种类少，而且丰富。 理论预测，体型较大的动物的特定代谢率较低，但它们的肠道大小却近似等长地增加。 因此，对体型的选择可能是由于较大动物从低质量食物中提取能量的效率更高。 将使用比较方法来检验这一假设。 尺寸的选择将在两个岛屿上进行测量——一个表现出巨人症，另一个则不表现出巨人症。 将测量和分析饮食成分和质量，然后将其与与体型相关的生物特征联系起来。