Evolution, Coevolution and Predator-Prey Dynamics: An Experimental Approach

进化、共同进化和捕食者-猎物动力学：一种实验方法

• 批准号: 9419660
• 负责人: Sharon Lawler
• 金额: $ 3万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-05-01 至 1997-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9419660&HistoricalAwards=false
• 关键词: Evolution; Coevolution; Predator; Prey; Dynamics

9419660 Lawler Evolutionary theory predicts that predators can cause evolutionary change in their prey and that predators may evolve in response to their prey. Such changes are thought to affect the population dynamics of both predators and prey. However, this important realm of evolutionary theory is practically untested because prolonged studies are required to observe evolution and population dynamics in most animals. This problem can be overcome by studying evolution in micro-organisms, which can evolve rapidly because their generation times are only 4-48 hours. It is crucial to discover whether evolution can alter population dynamics, to determine whether evolutionary processes need to be incorporated into population biology theory. Such knowledge may increase the ability of scientists to predict changes in population sizes. In this project, protozoan predators and their prey will be grown in replicated laboratory microcosms, where their population dynamics and other characteristics can be measured with comparative ease. The project consists of four sets of experiments, each on a different predator-prey pair. Prey will be grown for over 100 generations, in microcosms alone and with predators. A wide variety of predator and prey characters will be measured regularly during this time to quantify evolutionary changes. Population sizes will also be monitored. Subsequent experiments will measure the effect of evolution on predator-prey population dynamics. In these, predators from the first experiment will be grown with either of two types of prey: prey that have not coexisted with the predator for hundreds of generations, or prey that have. Differences in the population dynamics of the predator when grown on the two prey types will provide evidence that evolution affects population dynamics. This research will clarify whether population biologists need to consider evolutionary processes when constructing predictive models of population dynamics, and may establish whether coevolution o ccurs in predator-prey pairs. The theory that this research will test is potentially important to some problems in applied ecology. For example, it is important to know whether pest species can rapidly evolve resistance to predators introduced for biological control.

9419660劳勒进化理论预测，捕食者可以导致猎物的进化变化，捕食者可能会对猎物做出反应而进化。这种变化被认为会影响捕食者和猎物的种群动态。然而，这一重要的进化论领域实际上是未经检验的，因为需要进行长期的研究来观察大多数动物的进化和种群动态。这个问题可以通过研究微生物的进化来克服，微生物可以快速进化，因为它们的世代时间只有4-48小时。发现进化是否可以改变种群动态，确定进化过程是否需要纳入种群生物学理论，这是至关重要的。这些知识可能会增加科学家预测种群数量变化的能力。在这个项目中，原生动物捕食者及其猎物将在复制的实验室微观世界中生长，在那里可以相对容易地测量它们的种群动态和其他特征。该项目包括四组实验，每组实验针对不同的捕食者-猎物对。猎物将在100多个世代中生长，仅在微型宇宙中就会与捕食者一起生长。在此期间，将定期测量各种捕食者和猎物的特征，以量化进化变化。人口规模也将受到监测。随后的实验将测量进化对捕食者-猎物种群动态的影响。在这些实验中，第一次实验中的捕食者将与两种猎物中的任何一种一起生长：数百代没有与捕食者共存的猎物，或者已经与捕食者共存的猎物。当捕食者生长在两种猎物类型上时，捕食者种群动态的差异将提供进化影响种群动态的证据。这项研究将澄清种群生物学家在构建种群动态预测模型时是否需要考虑进化过程，并可能确定协同进化是否发生在捕食者-被捕食者对中。这项研究将检验的理论对应用生态学中的一些问题具有潜在的重要意义。例如，了解害虫物种是否能迅速进化出对引入生物防治的捕食者的抵抗力是很重要的。