Centers of marine fauna redistribution

Abstract

The concepts of centers of biota origin and centers of biota accumulation are usually regarded as mutually exclusive. In this paper, they are analyzed within the framework of a unified concept of centers of biota redistribution. Such a center is a biogeographic unit that has three developmental stages: accumulation, diversification, and dispersal. At the accumulation stage, the taxonomic capacity of the corresponding biogeographic district drastically increases and its species richness becomes higher owing to in-migration of species from other regions. At the diversification stage, the species richness continues to increase owing to speciation, and a unified succession system develops. At the dispersal stage, the biotic boundaries of the region act as efficient barriers to species invasion, and the species of the redistribution center gain an advantage over the species of adjacent regions when colonizing new habitats. In the Neogene, the main shallow-water centers of marine fauna redistribution were located in the Indo-Malayan triangle, the western Atlantic, and the northern Pacific. The role of redistribution centers in deep-ocean areas belonged to the Antarctic and the western Pacific. The possibility of using an ecosystem approach to the study of redistribution centers is discussed.