Historical biogeography of Caribbean plants: introduction to current knowledge and possibilities from a phylogenetic perspective

Knowledge of the evolution and biogeography of the Caribbean biota comes primarily from faunal studies, in spite of the tremendous richness of the Caribbean flora. The limited data to assess Caribbean phytogeography comes from fossils, floristic distributions, and phylogenetic studies. The geology in the Caribbean is extremely complex, but it is widely accepted that part of the Greater Antilles are old and precede the emergence of the Lesser Antilles and the Panamanian isthmus. Cuba and Hispaniola are each composed of a series of independent land blocks and Jamaica was mainly or entirely submerged during part of its history. Paleopalynological data, at present the only reliable source for reconstructing past plant communities, suggest warm–temperate to tropical conditions. Contemporary floristic data portray affinities with both Laurasian and Gondwanan derived plant groups. Shortcomings of traditional methodological approaches is a major criticism to studies assessing historical biogeography. Phylogenetics is an appropriate strategy to apply, because it: (1) elucidates the systematic relationships of taxa, (2) permits assessment of morphological and ecological evolution, and (3) illustrates the direction and sequence in which the distribution of a taxa originated. Study of Caribbean taxa with high levels of endemicity allows tracing the correspondence between taxa and geographic areas, and thus, permits application of a phylogeny for assessments of geographic relatedness under both dispersal and vicariant scenarios. Caribbean plant groups in several angiosperm families have now been studied phylogenetically. Some biogeographic patterns are starting to emerge from these studies, but more studies are needed for generalizations to be drawn.