Landscape Demography: Population Change and its Drivers Across Spatial Scales.

Demographic studies of plants and animals have a rich history and literature in ecology, and are important for both fundamental and applied ecology and conservation biology. Almost all demographic work has focused on intensive studies in which births, deaths, growth of individuals, and related measures are quantified in a single population or a few populations. This has been for practical reasons due to the high demands of labor required for this work, and because the questions addressed in these studies have been asked at the level of individual populations, with implicit assumptions about generalizing from the results. We introduce the concept of landscape demography, the study of the demographic properties of populations and their drivers at multiple spatial scales, and of how the relationships among populations and their drivers at any one scale influence demographic outcomes at other scales. We explore the ways in which considering the dynamics of ensembles of populations at different spatial scales can advance progress in thinking about ecological issues of high current interest such as biological invasions, range expansions and contractions due to climate change, and the decline of threatened species, as well as fundamental ecological and evolutionary questions.