DISSERTATION RESEARCH: The role of toxin complementation in herbivore defense

论文研究：毒素补充在草食动物防御中的作用

• 批准号: 1011503
• 负责人: Michael Singer
• 金额: $ 1万
• 依托单位: Wesleyan University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1011503&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; role; toxin; complementation

Herbivores with specialized diets can co-opt the defensive chemicals of their food-plants for their own defense. This research provides a first test of the hypothesis that grazing herbivores do the same, by regulating their intake of multiple plant chemicals to optimize defense against enemies. Alternatively, grazing among toxic plants might benefit herbivores by reducing the harmful effects of over-ingesting a single toxin associated with a particular food-plant species. These alternative hypotheses will be tested through three experiments involving a caterpillar already known to ingest one type of plant toxin as a defense against lethal parasites. First, the researcher will investigate how parasitism and the type of parasite affect the caterpillar's intake of two types of toxins (found in different food-plants). Second, she will compare caterpillar resistance against parasites when they have consumed the two toxins singly or in combination. To address toxin dilution, this experiment will also determine the effects of these diets on the survival and growth of unparasitized caterpillars. Finally, she will test whether the ratio of toxins eaten by unparasitized caterpillars confers deterrency against ubiquitous ant predators. Taken together, these results will identify how this herbivore benefits by grazing on toxic plants. This work will connect the science of pharmacology with animal behavior and ecology. Humans, domesticated grazing herbivores, and wild grazing herbivores face the common problem of obtaining a healthy diet from a chemically diverse array of plant foods. Using grazing caterpillars as a model, this research will test and develop scientific theory that can be applied to other species, including livestock and humans. In addition, understanding the reasons for host plant selection by herbivores will inform the management and conservation of biodiversity in grasslands, which are imperiled ecosystems and home to the caterpillars, plants, predators and parasites under study.

有特殊饮食的食草动物可以利用它们食用植物中的防御性化学物质来自卫。这项研究首次验证了这样一个假设，即食草动物通过调节它们对多种植物化学物质的摄取来优化对敌人的防御。或者，在有毒植物中放牧可能会减少过度摄取与特定食用植物物种相关的单一毒素的有害影响，从而使食草动物受益。这些替代假设将通过三个实验进行验证，这些实验涉及一种已知的毛虫，它摄取了一种植物毒素来防御致命的寄生虫。首先，研究人员将调查寄生虫和寄生虫的类型如何影响毛虫对两种毒素的吸收(在不同的食物植物中发现)。其次，她将比较毛虫对寄生虫的抵抗力，当它们单独或联合摄入这两种毒素时。为了解决毒素稀释问题，本实验还将确定这些饲料对未寄生毛虫存活和生长的影响。最后，她将测试未被寄生的毛虫所吃的毒素的比例是否对无处不在的蚂蚁捕食者具有威慑作用。综上所述，这些结果将确定这种食草动物是如何通过吃有毒植物而受益的。这项工作将把药理学与动物行为和生态学联系起来。人类、驯养的食草动物和野生的食草动物都面临着一个共同的问题，即如何从一系列化学成分多样的植物食物中获得健康的饮食。这项研究将以放牧毛虫为模型，测试和开发可应用于包括牲畜和人类在内的其他物种的科学理论。此外，了解草食动物选择寄主植物的原因将有助于草原生物多样性的管理和保护，草原是危险的生态系统，也是正在研究的毛虫、植物、捕食者和寄生虫的家园。