Figure 1. The giant Neotropical puzzle.

Map of the Neotropical region, spanning from Central Mexico to central Argentina (red dashed line) and including all Caribbean Islands. The figure shows examples of the large diversity of Neotropical habitats and the taxa that inhabit those habitats. We also outline a few of the many topics in Neotropical biodiversity that can be studied in the “trans-disciplinary biogeographic approach” advocated here. (A) Eastern slopes of the Bolivian Andes, where the Amazonian and Andean biotas meet; (B) Patagonian mountains of southern Chile, which despite being in the temperate zone of South America is home to many Neotropical-derived lineages; (C) Iguazu waterfalls, where increased humidity create gallery forests within the South American open diagonal; (D) Southern grasslands of the Pampas, a naturally open habitat now largely influenced by human activity; (E) One of the ca. 338 known species of hummingbirds, a conspicuous clade currently restricted to the American continent and particularly diverse in the Andes; (F) Epidendrum ibaguense, a widespread species in the orchid family in which many new Neotropical species are discovered each year; (G) An unidentified fly in the inselbergs of southern French Guiana, where basaltic rocks emerge several hundred meters above the surrounding Amazonian rainforest; (H) The large dogtooth characin fish Hydrolycus scomberoides, exemplifying the world’s richest ichthyofauna in the Amazon drainage basin; (I) Ameerega flavopicta, a rock-dwelling frog species adapted to a region of high seasonality of precipitation; (J) A columnar cactus of central Mexico, near the northwestern limits of the Neotropical region where low-canopy forests and succulent vegetation build vegetation mosaics across the landscape. Map generated through the remote-sensing ESA GlobCover 2009 project and colored by biome assignments (©ESA 2010 and UCLouvain; http://due.esrin.esa.int/page_globcover.php). Photo credits: A–G, I and J: A.A.; H: J.A.