Collaborative Research: Species Interactions in Range Dynamics and Changing Environments: Stochastic Models and Experiments

入侵物种的传播是一种鲜为人知的生态现象，但它具有重要的实际意义，每年造成约1200亿美元的损失。目前的理论在很大程度上考虑了单一物种入侵稳定栖息地的情况。这些模型不足以解决入侵前沿在整个地形上移动时入侵物种与竞争物种相互作用的现实情况。它们也没有考虑这样一个事实，即栖息地本身可能会因气候和其他环境变化而在景观上发生变化。例如，栖息地迅速向两极和更高海拔移动是当代的全球现象。这项研究项目将开发新的理论，以实验室中的模式物种实验为支持，解释物种入侵是如何由竞争物种的存在以及栖息地在景观上的变化情况所塑造的。这项工作将通过为预测入侵物种和气候驱动的物种范围变化提供更强有力的理论基础来推动生态科学的发展，并为土地管理者、公共卫生官员和关注入侵物种传播的保护生物学家提供有用的模型。这个项目将为从本科生到博士后学者的生物学家提供实践培训和经验，使他们成为解决生物学中复杂问题的下一代科学家的领导者。当考虑到两个或更多物种时，范围动力学出现了重要的新现象，特别是考虑到在任何物种范围的边缘，密度较低，随机性必须发挥重要作用。随机模型将与高度重复的微观世界实验一起开发，使用面粉甲虫模型系统。这项研究将决定：1)与居留物种的相互作用如何改变入侵者的范围扩展及其对居留物种的影响；2)物种相互作用和随机性如何在固定的异质环境中设定物种范围；以及3)物种相互作用、随机性和移动环境如何设置物种范围和改变空间群落结构。

The spread of an invasive species is a poorly understood ecological phenomenon, yet it is of great practical importance causing an estimated $120 billion in damages per year. Current theory largely considers the situation of a single species invading into a stable habitat. Those models are inadequate to address the realistic situation of invasive species interacting with competitor species as the invasion front moves across the landscape. They also do not incorporate the fact that habitats themselves can shift on the landscape as a result of climatic and other environmental changes. For example, rapid movement of habitats toward the poles and higher elevations is a contemporary, global phenomenon. This research project will develop new theory, backed by experiments with model species in the laboratory, to explain how species invasions are shaped by the presence of competitor species, and the situation of habitats shifting on the landscape. This work will advance ecological science by providing a stronger theoretical basis for projections of species range shifts driven by invasive species and climate, and provide models useful to land managers, public health officials, and conservation biologists concerned with the spread of invasive species. This project will provide hands on training and experience to biologists from undergraduate students to postdoctoral scholars, enabling them to become the leaders of the next generation of scientists tackling complex problems in biology.Important new phenomena for range dynamics emerge when two or more species are considered, and especially given that at the edge of any species range, densities are low, stochasticity must play an important role. Stochastic models will be developed together with highly replicated, microcosm experiments using a flour beetle model system. The research will determine 1) how interactions with a resident species modify the range expansion of an invader and its effect on the resident; 2) how species interactions and stochasticity set species ranges in stationary heterogeneous environments; and 3) how species interactions, stochasticity, and moving environments set species ranges and alter spatial community structure.