Biogeography aims to understand the temporal and spatial distribution of life on Earth. Biogeographical research is aimed not only at describing where organisms live, at what densities, with whom, and how it all relates to the environmental and geographical setting but also why this is so. The International Biogeography Society, IBS, is a young and vibrant international and interdisciplinary society contributing to the advancement of all studies of the geography of nature, including spatial ecology (<www.biogeography.org>). In January 2009, the 4th International Conference of the International Biogeography Society took place in Merida on the Yucatan Peninsula, Mexico. Ecography provided financial support, acting as the sponsor of the Symposium of Extinction Biogeography and contributing to student travel awards. In addition, Ecography was the officially designated journal for publishing some of the many exciting talks and posters presented at the conference. All of the papers in this special issue of Ecography arose from the IBS conference. They have all been subject to external peer review, subsequent revision, and final editorial decisions of acceptance/rejection.