The biology of spatially structured populations: concluding remarks

摘要

Population biologists and community ecologists have for a long time used study areas they considered as homogeneous, and have investigated the dynamics of biological systems through time with little or no attention to the spatial components of the dynamics. Among many examples of such approaches, one may cite landmark studies as diverse as those by HAMILTON (1966) on the evolution of life history strategies, BEVERTON & HOLT (1959) on density-dependent recruitment, and CODY & DIAMOND (1975) on the many studies that emerged from the Hutchinson-Mac Arthur paradigm of community ecology based on the niche concept. The early attention paid to space, explicitly considered as a limiting factor to population growth by MALTHUS (1798) and VERHULST (1838), did not for a long time lead to an interest in spatially based processes. One of the earliest disciplines to address spatial processes was population genetics (WRIGHT, 1937) although spatial heterogeneity was not fully considered. Early comments by ANDREV/ARTHA & BIRCH (1954) gave perceptive insights into colonisation-extinction processes in small isolated populations but, surprisingly, they have since been overlooked almost completely. It was not until LEVINS (1968, 1969), DEN BOER (1968) and WIENS (1976, 1989) and others that the importance of spatial heterogeneity in ecological and genetical processes was recognized at the population, community, or landscape levels. The introduction of the metapopulation concept (LEVINS, 1969) in population biology combined with reflections on the role of habitat Heterogeneity in population dynamics (BROWN, 1969) generated a flow of studies of great theoretical and practical interest (e.g. PULLIAM, 1988; GILPIN & HANSKI, 1991; HANSSON et ai, 1995).