Quantitative evaluations of species distributional congruence allow evaluating previously propose... more 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 ...
ABSTRACT Background Montes de María is the best-preserved tropical dry forest fragment in the Col... more ABSTRACT Background Montes de María is the best-preserved tropical dry forest fragment in the Colombian Caribbean, making it a good model to relate environmental and geographic factors to woody plant community structure. Aims We related alpha and beta diversity of woody plant communities to geographic distance and bioclimatic factors to understand the underlying factors of community structure. Methods We compared species composition among seven sites and calculated alpha (using effective numbers of species) and beta diversity using Whitaker and Bray–Curtis dissimilarity index. Canonical correspondence analysis (CCA) and a Mantel test were used to quantify how community structure was related to environmental and/or geographic distance. Results We found that Montes de María is as diverse as other dry forest fragments in Colombia. We detected three groups of communities which were shaped mainly by turnover associated with both precipitation and geographic distance. Conclusions The high beta diversity of the dry forest of Montes de María is related to a mixture of environmental variation and geographic distance.
Figure 1. Ecological niche modelling projected as potential (based on the natural vegetation, t1)... more Figure 1. Ecological niche modelling projected as potential (based on the natural vegetation, t1) and extant (based on land use and natural vegetation, t2) distribution of two terrestrial mammals. Black areas depict part of distributions of (a) Chaetodipus spinatus in the Baja California Peninsula, and (b) Cabassous centralis in Chiapas.
FIGURE 1. Map of the regionalization of the Nearctic region, including three subregions, one tran... more FIGURE 1. Map of the regionalization of the Nearctic region, including three subregions, one transition zone and 29 provinces.
We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based o... more We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based on published regionalizations, especially Dice (1943), and applying the International Code of Area Nomenclature. The Nearctic region is comprised of three subregions (one of them with two dominions), one transition zone and 29 provinces. The Arctic subregion, in northern North America and Greenland, includes the Eskimoan, Hudsonian, Aleutian and Sitkan provinces. The Western subregion, in western North America, includes the Californian dominion, with the Californian and Oregonian provinces; and the Rocky Mountain dominion, including the Montanian, Saskatchewan, Palusian, Artemisian, Coloradan, Kansan, Mohavian, Navahonian, Sonoran, Chihuahuan, Comanche, and Baja California provinces. The Alleghany subregion, in eastern North America, includes the Illinoian, Canadian, Carolinian, Texan, Austroriparian, and Tamaulipan provinces. The Mexican Transition Zone, situated in the area of overlap w...
Los estudios sobre las áreas de distribución geográfica (ADG) proporcionan información sobre cómo... more Los estudios sobre las áreas de distribución geográfica (ADG) proporcionan información sobre cómo se establecen las especies en el espacio y tiempo, y los efectos del cambio de uso de suelo sobre los patrones geográficos de la biodiversidad. En la provincia biogeográfica de la Faja Volcánica Transmexicana (FVT) habita un alto número de especies endémicas; sin embargo, presenta altas tasas de deforestación. En el presente trabajo: (a) se describen cuantitativa y cualitativamente las ADG histórica de 167 especies de anfibios, aves, insectos, mamíferos y plantas endémicas de la FVT, y (b) se analiza el efecto del cambio de uso de suelo actual en esas distribuciones geográficas. En general, la clase Mammalia tuvo las mayores superficies ocupadas, el promedio más alto de las tres magnitudes y fue principalmente de distribución continental. Por otro lado, la mayoría de las especies fueron transicionales y discontinuas. Considerando el cambio en el uso del suelo, el 85% de las especies tuv...
We provide a map of the 14 biogeographic provinces of Mexico based on the ecoregions recognized f... more We provide a map of the 14 biogeographic provinces of Mexico based on the ecoregions recognized for the country, which combine climatic, geological and biotic criteria. These provinces belong to the Nearctic region (Californian, Baja Californian, Sonoran, Chihuahuan Desert and Tamaulipas provinces), Neotropical region (Pacific Lowlands, Balsas Basin, Veracruzan and Yucatán Peninsula provinces) and the Mexican transition zone (Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur and Chiapas Highlands provinces). In order to facilitate future biogeographic analyses, we provide a file of the biogeographical regionalisation of Mexico by converting the map into a polygon shapefile and a raster file with all provinces. We also separately provide each of the provinces in vector and raster format. All the maps are in geographical and Lambert Conformal Conic projections.
Track analysis is the core of panbiogeographic analysis. In this work, we reflect on the formaliz... more Track analysis is the core of panbiogeographic analysis. In this work, we reflect on the formalization of track analysis, its methodological issues, and interpretations by using new software developments and from a contemporary evolutionary biogeographical viewpoint. From a geometric perspective, we analyze the meaning of a minimal spanning tree, considering that Prim’s algorithm is the most commonly used to draw individual tracks. We then show the existing methodologies (graphs, PAE, combined method, AE) and software packages (Trazos2004, Croizat, Martitracks, fossil) used to perform track analysis. Finally, we illustrate a track analysis using Nearctic mammals as an example. Based on our review, connectivity matrix analysis may be the best way to associate individual tracks into generalized tracks because it compares the minimal spanning tree topologies. However, it is the most demanding of all methods, since it requires a high spatial congruence among species, and therefore more algorithmic development.
Quantitative evaluations of species distributional congruence allow evaluating previously propose... more 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 ...
ABSTRACT Background Montes de María is the best-preserved tropical dry forest fragment in the Col... more ABSTRACT Background Montes de María is the best-preserved tropical dry forest fragment in the Colombian Caribbean, making it a good model to relate environmental and geographic factors to woody plant community structure. Aims We related alpha and beta diversity of woody plant communities to geographic distance and bioclimatic factors to understand the underlying factors of community structure. Methods We compared species composition among seven sites and calculated alpha (using effective numbers of species) and beta diversity using Whitaker and Bray–Curtis dissimilarity index. Canonical correspondence analysis (CCA) and a Mantel test were used to quantify how community structure was related to environmental and/or geographic distance. Results We found that Montes de María is as diverse as other dry forest fragments in Colombia. We detected three groups of communities which were shaped mainly by turnover associated with both precipitation and geographic distance. Conclusions The high beta diversity of the dry forest of Montes de María is related to a mixture of environmental variation and geographic distance.
Figure 1. Ecological niche modelling projected as potential (based on the natural vegetation, t1)... more Figure 1. Ecological niche modelling projected as potential (based on the natural vegetation, t1) and extant (based on land use and natural vegetation, t2) distribution of two terrestrial mammals. Black areas depict part of distributions of (a) Chaetodipus spinatus in the Baja California Peninsula, and (b) Cabassous centralis in Chiapas.
FIGURE 1. Map of the regionalization of the Nearctic region, including three subregions, one tran... more FIGURE 1. Map of the regionalization of the Nearctic region, including three subregions, one transition zone and 29 provinces.
We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based o... more We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based on published regionalizations, especially Dice (1943), and applying the International Code of Area Nomenclature. The Nearctic region is comprised of three subregions (one of them with two dominions), one transition zone and 29 provinces. The Arctic subregion, in northern North America and Greenland, includes the Eskimoan, Hudsonian, Aleutian and Sitkan provinces. The Western subregion, in western North America, includes the Californian dominion, with the Californian and Oregonian provinces; and the Rocky Mountain dominion, including the Montanian, Saskatchewan, Palusian, Artemisian, Coloradan, Kansan, Mohavian, Navahonian, Sonoran, Chihuahuan, Comanche, and Baja California provinces. The Alleghany subregion, in eastern North America, includes the Illinoian, Canadian, Carolinian, Texan, Austroriparian, and Tamaulipan provinces. The Mexican Transition Zone, situated in the area of overlap w...
Los estudios sobre las áreas de distribución geográfica (ADG) proporcionan información sobre cómo... more Los estudios sobre las áreas de distribución geográfica (ADG) proporcionan información sobre cómo se establecen las especies en el espacio y tiempo, y los efectos del cambio de uso de suelo sobre los patrones geográficos de la biodiversidad. En la provincia biogeográfica de la Faja Volcánica Transmexicana (FVT) habita un alto número de especies endémicas; sin embargo, presenta altas tasas de deforestación. En el presente trabajo: (a) se describen cuantitativa y cualitativamente las ADG histórica de 167 especies de anfibios, aves, insectos, mamíferos y plantas endémicas de la FVT, y (b) se analiza el efecto del cambio de uso de suelo actual en esas distribuciones geográficas. En general, la clase Mammalia tuvo las mayores superficies ocupadas, el promedio más alto de las tres magnitudes y fue principalmente de distribución continental. Por otro lado, la mayoría de las especies fueron transicionales y discontinuas. Considerando el cambio en el uso del suelo, el 85% de las especies tuv...
We provide a map of the 14 biogeographic provinces of Mexico based on the ecoregions recognized f... more We provide a map of the 14 biogeographic provinces of Mexico based on the ecoregions recognized for the country, which combine climatic, geological and biotic criteria. These provinces belong to the Nearctic region (Californian, Baja Californian, Sonoran, Chihuahuan Desert and Tamaulipas provinces), Neotropical region (Pacific Lowlands, Balsas Basin, Veracruzan and Yucatán Peninsula provinces) and the Mexican transition zone (Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur and Chiapas Highlands provinces). In order to facilitate future biogeographic analyses, we provide a file of the biogeographical regionalisation of Mexico by converting the map into a polygon shapefile and a raster file with all provinces. We also separately provide each of the provinces in vector and raster format. All the maps are in geographical and Lambert Conformal Conic projections.
Track analysis is the core of panbiogeographic analysis. In this work, we reflect on the formaliz... more Track analysis is the core of panbiogeographic analysis. In this work, we reflect on the formalization of track analysis, its methodological issues, and interpretations by using new software developments and from a contemporary evolutionary biogeographical viewpoint. From a geometric perspective, we analyze the meaning of a minimal spanning tree, considering that Prim’s algorithm is the most commonly used to draw individual tracks. We then show the existing methodologies (graphs, PAE, combined method, AE) and software packages (Trazos2004, Croizat, Martitracks, fossil) used to perform track analysis. Finally, we illustrate a track analysis using Nearctic mammals as an example. Based on our review, connectivity matrix analysis may be the best way to associate individual tracks into generalized tracks because it compares the minimal spanning tree topologies. However, it is the most demanding of all methods, since it requires a high spatial congruence among species, and therefore more algorithmic development.
La identificación de las áreas de endemismo es un paso fundamental en los análisis de biogeografí... more 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 s... more 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
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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