Why do species live where they live? What determines the abundance and diversity of species in a given area? What role do species play in the functioning of entire ecosystems? All of these questions share a single core concept—the ecological niche. Although the niche concept has fallen into disfavor among ecologists in recent years, Jonathan M. Chase and Mathew A. Leibold argue that the niche is an ideal tool with which to unify disparate research and theoretical approaches in contemporary ecology.

Chase and Leibold define the niche as including both what an organism needs from its environment and how that organism's activities shape its environment. Drawing on the theory of consumer-resource interactions, as well as its graphical analysis, they develop a framework for understanding niches that is flexible enough to include a variety of small- and large-scale processes, from resource competition, predation, and stress to community structure, biodiversity, and ecosystem function. Chase and Leibold's synthetic approach will interest ecologists from a wide range of subdisciplines.

Until recently community ecology—a science devoted to understanding the patterns and processes of species distribution and abundance—focused mainly on specific and often limited scales of a single community. Since the 1970s, for example, metapopulation dynamics—studies of interacting groups of populations connected through movement—concentrated on the processes of population turnover, extinction, and establishment of new populations.

Metacommunities takes the hallmarks of metapopulation theory to the next level by considering a group of communities, each of which may contain numerous populations, connected by species interactions within communities and the movement of individuals between communities. In examining communities open to dispersal, the book unites a broad range of ecological theories, presenting some of the first empirical investigations and revealing the value of the metacommunity approach.

The collection of empirical, theoretical, and synthetic chapters in Metacommunities seeks to understand how communities work in fragmented landscapes. Encouraging community ecologists to rethink some of the leading theories of population and community dynamics, Metacommunities urges ecologists to expand the spatiotemporal scales of their research.