DISSERTATION RESEARCH: Proximate Causes and Adaptive Significance of Individual Variation in the Behavior of Kangaroo Rats

论文研究：袋鼠行为个体差异的直接原因和适应性意义

• 批准号: 0206068
• 负责人: Stephen Jenkins
• 金额: $ 0.94万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206068&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Proximate; Causes; Adaptive

PROXIMATE CAUSES AND ADAPTIVE SIGNIFICANCE OF INDIVIDUAL VARIATION IN THE BEHAVIOR OF KANGAROO RATSDr. Stephen H. JenkinsAmy M. BarberComparative studies of closely related species or different populations of the same species have contributed greatly to our understanding of the evolutionary significance of various kinds of behavior. More recently, researchers have begun to focus on variation among individuals in the same population, especially individuals belonging to the same age and sex class. Study of this kind of variation holds as much promise for advancing understanding of the evolution of behavior in the future as study of interspecific variation and geographic variation within species has contributed to such understanding in the past. There are several recent reports of intraspecific variation in diverse behavioral traits. Some of this variation is organized into syndromes that are correlated with differences in hormone levels; these syndromes have been described as different strategies that may be important for how individuals interact with one another or their environment. However, most of this work has been done in the laboratory and so is unable to address how these different behaviors function under natural conditions.This study of Merriam's kangaroo rats (Dipodomys merriami) builds upon the current evidence by using an experimental approach in the field. Corticosterone is a major stress hormone in kangaroo rats and other animals and is an important basis, or proximate mechanism, for a variety of behaviors. Levels of corticosterone will be altered within the natural range for kangaroo rats using hormone implants of corticosterone to increase levels and metyrapone implants to decrease the natural production of corticosterone. These manipulations will be used to examine how individual differences in behavior change in response to changes in hormone levels. A newly developed technique for sampling hormones in the feces of rodents will be used to non-invasively measure differences in hormone profiles among individuals. The foraging behavior, spatial memory ability, and response of focal individuals to novel situations will be measured to quantify behavioral differences both before and after manipulation of hormone levels. In addition, the consistency of behavior will be characterized for focal animals. Modification of typical laboratory methods for use in the field will allow focal animals to remain in their natural habitat for a longer-term study; most importantly, the survival of individuals will be monitored in relation to their corticosterone levels and behavior over the course of the study. Survival is one key measure of the adaptive significance of behavior for kangaroo rats.This study, using a population of kangaroo rats in the field as a model system, provides a unique opportunity to understand in detail how individual variation in hormones influences the survival of individuals through its effects on a suite of interrelated behaviors. The study will also provide both graduate and undergraduate training.

袋鼠老鼠行为个体变异的近因及其适应性意义斯蒂芬·H·詹金斯（Stephen H. Jenkins）艾米·M·巴伯（Amy M. Barber）对密切相关的物种或同一物种的不同种群的比较研究极大地促进了我们对各种行为的进化意义的理解。最近，研究人员开始关注同一人群中个体之间的差异，特别是属于同一年龄和性别阶层的个体。对这种变异的研究对于增进对未来行为进化的理解有着同样的希望，就像对种间变异和物种内地理变异的研究在过去对这种理解的贡献一样。最近有一些关于不同行为特征的种内变异的报道。其中一些变异被组织成与激素水平差异相关的综合症。这些综合症被描述为不同的策略，这些策略对于个体如何与他人或与环境互动可能很重要。然而，这项工作大部分是在实验室中完成的，因此无法解决这些不同行为在自然条件下如何发挥作用。这项对梅里亚姆袋鼠（Dipodomys merriami）的研究基于当前的证据，采用了现场实验方法。皮质酮是袋鼠和其他​​动物的主要应激激素，是多种行为的重要基础或直接机制。使用皮质酮激素植入物来增加皮质酮水平，并使用甲吡酮植入物来减少皮质酮的自然产生，袋鼠的皮质酮水平将在自然范围内改变。 这些操作将用于检查个体行为差异如何随着激素水平的变化而变化。一种新开发的啮齿动物粪便激素采样技术将用于非侵入性测量个体之间激素分布的差异。将测量焦点个体的觅食行为、空间记忆能力和对新情况的反应，以量化激素水平操纵前后的行为差异。此外，还将表征焦点动物的行为一致性。对现场使用的典型实验室方法进行修改将使焦点动物能够留在其自然栖息地进行长期研究；最重要的是，在研究过程中，将根据皮质酮水平和行为监测个体的生存情况。生存是衡量袋鼠行为适应性重要性的一个关键指标。这项研究使用现场袋鼠群体作为模型系统，提供了一个独特的机会来详细了解激素的个体差异如何通过其对一系列相互关联的行为的影响来影响个体的生存。该研究还将提供研究生和本科生培训。