1. Department of Biology; University of Puerto Rico; PO Box 23360; San Juan; PR; 00931-3360; U.S.A
2. Department of Geography and Global Studies; Center for Interdisciplinary Geospatial Analysis; Sonoma State University; Rohnert Park; CA; 94928; U.S.A
3. CONICET; Instituto de Ecología Regional; Universidad Nacional de Tucumán; Casilla de Correo 34 (4107); Yerba Buena; Tucumán; Argentina
4. Department of Geography; University of California; Ellison Hall 3611; Santa Barbara; CA; 93106; U.S.A
5. Center for International Earth Science Information Network; Earth Institute; Columbia University; 61 Route 9W; Palisades; NY; 10964; U.S.A
6. Red de Ambiente y Sustentabilidad; Instituto de Ecología; A.C. Carretera antigua a Coatepec, 351 El Haya C.P.; 91070; Xalapa; Veracruz; Mexico