Biogeography of the Tropical Pacific

Abstract

Many previous biogeographic regionalizations of the islands and reefs of the tropical Pacific are unsatisfactory: the regions as defined are heterogeneous, localities with unlike biotas are grouped together, and those with similar characteristics are placed in separate categories. Often distinctions appear to be based on cultural or political rather than biogeographic considerations. Criteria are defined for the establishment of biogeographic boundaries. Instead of the hierarchical schemes often utilized, it is proposed that the basis of biogeographic regionalization be typological. A distinction is made between the biogeographic characteristics of atolls and other reef islands, elevated limestone (makatea) islands, and high (often volcanic) islands. It is concluded that if the first two categories are filtered out, the treatment of the biogeography of the third group and hence the regionalization of the Pacific becomes relatively unproblematical.