Biogeography and Biotic Assembly of Indo-Pacific Corvoid Passerine Birds

Abstract

The archipelagos that form the transition between Asia and Australia were immortalized by Alfred Russel Wallace's observations on the connections between geography and animal distributions, which he summarized in what became the first major modern biogeographic synthesis. Wallace traveled the island region for eight years, during which he noted the marked faunal discontinuity across what has later become known as Wallace's Line. Wallace was intrigued by the bewildering diversity and distribution of life he discovered. But even today we ask ourselves how species formed within the region and why they are not evenly distributed. Biogeography, phylogeny, dispersal, biotic interactions, and abiotic factors affect the assembly of diversity. On the basis of a decade of research on the ecology, evolution, and systematics of corvoid passerine birds, we summarize what we have learned about the biogeography and assembly of island bird diversity. Corvoid passerine birds include nearly 800 species and 2,300 named taxa and thus represent a large, well-described, and globally distributed clade. Understanding the processes influencing biodiversity in this group is certain to deepen our general understanding of ecology and evolution in the context of biogeography and faunal assembly.