ABSTRACT
Few global phenomena rival the final closure of the Isthmus of Panama for bioregional high drama. The earth’s tectonic theatrics spawned a bioregion whose global importance far outweighs its small size. The closure of the isthmus created an oceanic dam that redirected the warm waters of the Gulf Stream north, making Northern Europe habitable, while launching a new era of marine speciation in two oceans (Ross 1996). Conversely, the land bridge between North and South America, often referred to in its bioregional context as the Mesoamerican Biological Corridor, created a migratory corridor for flora and fauna-and a route of human passage for the colonists (Stehli and Webb 1985). The legacy of colonialism has threatened many of the original inhabitants of all taxa with extinction and resulted in the political and biological fragmentation of the Mesoamerican Bioregion.
