Tania Escalante

Quantitative evaluations of species distributional congruence allow evaluating previously proposed biogeographic regionalization and even identify undetected areas of endemism. The geographic scenery of Northwestern Argentina offers ideal conditions for the study of distributional patterns of species since the boundaries of a diverse group of biomes converge in a relatively small region, which also includes a diverse fauna of mammals. In this paper we applied a grid-based explicit method in order to recognize Patterns of Distributional Congruence (PDCs) and Areas of Endemism (AEs), and the species (native but non-endemic and endemic, respectively) that determine them. Also, we relate these distributional patterns to traditional biogeographic divisions of the study region and with a very recent phytogeographic study and we reconsider what previously rejected as 'spurious' areas. Finally, we assessed the generality of the patterns found. The analysis resulted in 165 consensus ...

We provide a map and shapefi le of the 57 biogeographic provinces of the Neotropical region. Recognition of these provinces is based on their endemic species, but their delimitation on the map is based on ecoregions combining climatic, geological, and biotic criteria. These provinces belong to the Antillean, Brazilian and Chacoan subregions, and the Mexican and South American transition zones. We provide a vector fi le of the biogeographical regionalization by converting the map into a polygon shapefi le and a raster fi le with all provinces.

La identificación de las áreas de endemismo es un paso fundamental en los análisis de biogeografía evolutiva. Las áreas de endemismo han sido definidas por la congruencia de dos o más áreas de distribución, en donde se asume de manera general que los taxones endémicos tienen una respuesta geográfica similar a factores históricos y ambientales. Los mamíferos tienen alta diversidad en el Neotrópico y muchos de ellos han evolucionado en conjunto con esta región biogeográfica. Sin embargo, hay pocas hipótesis de áreas de endemismo que puedan ser relacionadas con la evolución de los mamíferos en el Neotrópico. En este estudio se identificaron las áreas de endemismo de los mamíferos neotropicales a partir del análisis de una matriz de 2052 taxones (familias, géneros y especies). Para ello se aplicó una búsqueda de áreas de endemismo con el método de Análisis de Endemicidad a una cuadrícula de 2° latitud-longitud. Se identificaron 101 áreas de endemismo y 498 taxones endémicos, las áreas coincidieron parcialmente con 65 patrones biogeográficos identificados por otros autores. La región Neotropical está compuesta por nueve áreas de endemismo y mostró múltiples límites, que sugieren un patrón dinámico. Se identificaron dos áreas complejas de intercambio biótico que coincidieron con las zonas de transición Mexicana y Sudamericana. La congruencia de las áreas de endemismo de mamíferos con otros esquemas biogeográficos sugiere que estas áreas han sido formadas tanto por factores históricos como ecológicos. Por otra parte, las incongruencias de las áreas de endemismo soportan un sistema biogeográfico no jerarquizado.

If one were to put all the elements of biogeography together in one picture the result might be something like the cover photograph by César Miguel Talonia. The view presented is one of sea, lowlands, and mountains – all the principal components in the evolution of landscapes and life. How, when, and where these factors have in-fluenced each other is an enduring question for biogeographers - whether one’s concern is with local questions of habitat and climate, the role of geology and tec-tonics, the origin of individual lineages, or the development of biogeographic meth-ods and biogeographic classification.With such a wide range of prospective considerations it is no wonder that the science of biogeography remains a dynamic and challenging subject. And per-haps it always will be. Perhaps there will never be a ‘unified’ synthesis and maybe there need not be. Diversity of theories, ideas, method, insights – these are what prevent the science of biogeography from becoming dull and boring.

The broad scope and range of biogeographic investigation continues to be evident in volume 8 of Biogeografía, and begins with the two Lead Articles. Techni-cal advances in methodology, especially computer aided algorithms, can some-times have a mesmerizing hold on our imagination and it is all too tempting to find a solution at the click of a mouse. But as Robert Anderson points out for the study of ecology and distribution, it is not just a matter of ‘click, click, click! The second lead article by Ignacio Ferro also explores conceptual and methodological issues, this time in reference to the concept of biogeographic affinity and different ways this may be understood with respect to geography and topography, particularly with ref-erence to the identification of transition from one biogeographic affinity to another.
Biogeography may often seem like an esoteric academic subject, but it can have potential or even actual influence on our stewardship of the planet. The practi-cal considerations for this goal are, however, quite daunting as outlined by Tania Escalante and Ricardo Morales who emphasize the need to continue developing both the methodology and theory of biogeography to improve practical approaches to conserving biodiversity. And perhaps equally challenging is to understand the ‘foot print’ of the geological past on the present as López-Almirall reflects in his arti-cle on the origins of the Neotropical flora.

The final two articles concern SEBA. Tania Escalante and José Carlos Guer-rero reviewed SEBA membership, noting that the council now has representatives of almost all continents, and that a survey supported transforming the Bulletin to open access journal – a goal that would rely on active participation and commitment of all members. Journals succeed by their content and willingness of people to review arti-cles. One aspect of biogeography that is still largely absent from the literature is the personal experience of biogeography – which individuals work on and what excites them in their work and their actual experiences with places and the study of animals and plants. Personal experiences may seem personally mundane, but to everyone else they can be a new window into the world. We hope to see more of this kind of input in the future. And it seems all the more appropriate that this volume of the Bulle-tin concludes with a review of the second SEBA meeting by César Miguel Talonia that again highlights the diversity of biogeographic thinking, and also raises some ex-tremely critical pragmatic questions such as the biogeographic impacts of climate change. We look forward to seeing more of this diversity continue in the Bulletin or its successor journal.

John Grehan
Tania Escalante
Elkin Noguera-Urbano
César Miguel-Talonia
Editors, SEBA Bulletin, 2015