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

身体大小影响生理、行为和群落 水平的相互作用，但实际上知之甚少 关于控制它的因素。小型哺乳动物食草动物， 孤立在岛屿上，没有捕食和竞争 压力，提供了一个理想的情况下选择的研究 尺寸 岛上的食草动物靠食物供应生存， 只不过种类少一些，但数量也比大陆栖息地少一些。 理论预测，较大的动物将具有较低的特异性， 代谢率，但他们的肠道大小增加约 等距地。 因此，对身体尺寸的选择可能是由于 更大的动物在提取能量的效率更高， 低质量的食物。 将使用比较方法来测试 这个假设。 尺寸的选择将在两个 岛屿-一个展示了非殖民主义，一个没有。 将测量和分析饮食成分和质量， 然后与大小相关的生物特征相关。

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.