The Anderson lab: Biogeography













My lab conducts biogeographic studies at the interface between ecology and evolution. We study spatial patterns of environmental suitability (e.g., for a particular species) and their ecological and evolutionary consequences. To do so, the lab develops and applies GIS-based methods of modeling species geographic ranges using environmental data and occurrence records from natural history museums. In addition to these techniques of general application to biogeography and conservation, Neotropical mammals represent my taxonomic and geographic specialty. I received a Ph.D. at the University of Kansas under the supervision of Dr. Robert M. Timm and subsequently conducted postdoctoral research at the American Museum of Natural History, sponsored by Dr. Robert S. Voss.

Recently, we produced two R packages (spThin and ENMeval) and a beta version of a software ("Wallace") that allows users to access some of their functionalities via a webpage (see Press).

In 2011, I was selected by the New York Academy of Sciences as a finalist for the Blavatnik Awards for Young Scientists, (direct link) which recognize impactful, innovative, and interdisciplinary accomplishments in the life sciences, physical sciences, mathematics, and engineering. See Anderson Blavatnik profile.

In August 2011, my lab began work on a grant from the National Science Foundation (Systematics and Biodiversity Science Program, Division of Environmental Biology) entitled “Testing species limits, phylogeographic concordance, and niche evolution in Madagascar's endemic small mammals." Based on linked collaborative proposals with Dr. Link Olson (University of Alaska, Fairbanks) and Dr. Sharon A. Jansa (University of Minnesota), the grant commenced 15 August 2011 and runs to 31 July 2015 (see below).

In August 2011, my lab completed a grant from the National Science Foundation (DEB-0717357; Systematic Biology and Biodiversity Inventories Program, Division of Environmental Biology) entitled “Integrating systematics and GIS modeling: biogeography of spiny pocket mice (Heteromyidae) in South America." Read more

In addition, in 2011 Mariano Soley (co-PI; see People) and I received a grant from the PSC-CUNY (Professional Staff Congress of the CIty University of New York) entitled "Effects of Quaternary climatic oscillations on the evolution of small mammals in the highlands of Costa Rica and western Panama" to fund fieldwork in Costa Rica.


My interdisciplinary research program includes three interconnected areas detailed below:

Modeling species distributions using GIS

Evolution and biogeography of insular faunas

Taxonomic and phylogenetic studies (including fieldwork)

Modeling species distributions using GIS:

At the forefront of my current research agenda is use of species occurrence localities (especially museum records), environmental data, and Geographic Information Systems (GIS) to model species geographic distributions (Anderson, 2012).  The niche-based nature of these models allows for synthetic studies of evolutionary ecology and biogeography (Anderson 2003, Anderson et al., 2002a, b, 2003).  These techniques are also relevant to global climate change, invasive species management, and conservation biology.  For instance, I modeled the rare species Heteromys teleus endemic to western Ecuador, estimating the location of remaining areas of suitable habitat for the species (Anderson and Martínez-Meyer, 2004).  My undergraduate student Mariya Shcheglovitova repeated these analyses with new techniques and environmental data (see People), to guide field surveys later conducted by our Ecuadorian collaborator Santiago Burneo and students.

Currently, my students and I are working to integrate GIS distributional modeling into evolutionary and biogeographic studies based on morphological and genetic information.  This work is supported by a grant from the National Science Foundation (Systematics and Biodiversity Science Program, Division of Environmental Biology) entitled “Testing species limits, phylogeographic concordance, and niche evolution in Madagascar's endemic small mammals." Based on linked collaborative proposals with Dr. Link Olson (University of Alaska, Fairbanks) and Dr. Sharon A. Jansa (University of Minnesota), we are further developing niche models and using them to study the effects of past climatic changes on the evolution and biogeography of small mammals in Madagascar. Specifically, we are combining niche models and phylogeographic analyses that characterize genetic differences among populations across the range of each species. This project continues a similar line of research, at a higher taxonomic level, funded by a previous grant from the National Science Foundation (DEB-0717357; Systematic Biology and Biodiversity Inventories Program, Division of Environmental Biology) entitled “Integrating systematics and GIS modeling: biogeography of spiny pocket mice (Heteromyidae) in South America."  For the comparative aspects of that research, we collaborated with Dr. Duke S. Rogers and his students at Brigham Young University, who sequenced mitochondrial and nuclear DNA and conducted phylogenetic analyses. Read more.

Over the past several years, I have worked in the development and use of techniques from machine learning (Maxent; Maximum entropy methods) to model species distributions.  In this research, I collaborated with Dr. Steven J. Phillips at AT&T-Research and Dr. Robert E. Schapire at Princeton, and Dr. Miroslav Dukík (then also at Princeton; now at Yahoo).  Their Maxent software is available for download, and their websites provide documentation on Maxent.  We successfully applied it to the distributions of two species of Neotropical mammals (Bradypus variegatus and Microryzomys minutus; Phillips et al., 2006).  Maxent is among the highest-performing techniques for modeling species distributions with presence-only data (see Elith et al., 2006) and is being used by myriad researchers worldwide (Google scholar).

My students and I continue to develop and use Maxent, making contributions relevant to other techniques for modeling species distributions as well.  We are applying it to study the evolution, biogeography, and conservation of small mammals in Madagascar and South America (see NSF grants, above), as well as using it in our studies of montane mammals in Venezuela, Costa Rica, and Panama (see fieldwork and Evolution of insular faunas, below; work with Eliécer Gutiérrez and Mariano Soley; see People).  Furthermore, we are conducting methodological studies to increase the robustness of Maxent to biases in sampling (Anderson and Gonzalez, 2011; see also work with Mariya Shcheglovitova and Aleks Radosavljevic; see People) and to clarify principles for selecting the appropriate study region for modeling species distributions (Anderson and Raza, 2010).

I was involved in a collaborative book project synthesizing the field of ecological niche modeling and led by A. Townsend Peterson. It was published in 2011 at Princeton University Press (see Publications). We hope that these years of effort have led to a product that proves helpful to diverse readers.


Predictive potential distributional model of Bradypus variegatus in the Neotropics; from Phillips et al., 2006; locality data from Anderson and Handley, 2001.

Evolution and biogeography of insular faunas:

The second branch of my research concerns factors affecting the evolution and biogeography of insular populations. Although important differences exist, empirical research on both habitat islands and real islands is relevant to the study and long-term management of landscapes fragmented by human activities.

The field program I have in Venezuela (see below) closely relates to the study of insular faunas, since the montane forests of northwestern Venezuela represent "ecological islands" or "habitat islands" (see photographs at the bottom of this page).  However, the degree of isolation varies among species.  Currently, my students and I are using GIS models (see above) to estimate the suitable distributional areas of each species, allowing us to quantify their level of isolation.  We are testing the prediction that more-isolated species exhibit greater morphological and genetic differentiation.  This work is in collaboration with Dr. José Ochoa-G. and Dr. Marisol Aguilera (see Anderson et al., 2012 for an overview of biogeographic patterns in the region).

I also have studied real islands, focusing on dwarfism and speciation in three-toed sloths of the landbridge islands of Bocas del Toro, Panama, which were formed in the past 10,000 years by rising sea levels (Anderson and Handley, 2001, 2002). I am collaborating with Dr. Link Olson (University of Alaska), who is sequencing mitochondrial DNA in order to elucidate molecular patterns of diversification among populations of insular and mainland sloths for comparison with my morphological framework and the sequence of island formation. Because excellent collections of mammals from this region exist at the Smithsonian Institution, the islands and mainland of Bocas del Toro represent a superb study system for integrated tests of evolutionary and community ecology theory in an insular fauna for our future studies with a multi-species perspective.


Map of the archipelago of Bocas del Toro, with an insert map showing its position within Panama; modified from Anderson and Handley, 2001

Map of northern Falcón, Venezuela, showing the Istmo de los Médanos, which connects the Península de Paraguaná to the "mainland."  Note the Serranía de San Luis (the east-west mountain range in the south) and the Cerro Santa Ana (the tiny, circular mountain on the Península de Paraguaná (see Anderson et al., 2012).

Taxonomic and phylogenetic studies (including fieldwork):

I have undertaken revisionary work on poorly known genera of mammals from the northern and central Neotropics (Mexico to Brazil). My goals here are to elucidate species boundaries (e.g., Anderson, 1999; Anderson and Soriano, 1999), describe new species (Anderson and Handley, 2001; Anderson and Jarrín-V., 2002; Anderson, 2003; Anderson and Timm, 2006; Anderson and Gutiérrez, 2009), and elucidate phylogenetic relationships (Gómez-Laverde et al., 2004; Anderson et al., 2006; Anderson and Jansa, 2007). My collection-based studies also provide extensive data sets for subsequent evolutionary and biogeographic analyses, as well as conservation assessments.

Skulls of Heteromys australis and Heteromys anomalus; modified from Anderson, 1999

Participants, IUCN (World Conservation Union) Global Mammal Assessment, Andean small mammals workshop, Villa de Leyva, Boyacá, Colombia, 6–10 February 2006.  I am standing behind Belkis Rivas, who is wearing a pink shirt.


For molecular research conducted by collaborators, new collections of key species are necessary. I have conducted modern inventories for mammals through field work in Colombia, Costa Rica, Guyana, and Venezuela (Cadena et al., 1998; Lim et al., 1999; Anderson et al., 2012). I am fluent in Spanish and have a strong intellectual and personal commitment to Latin America. This has facilitated successful collaborations with scientists from Colombia, Ecuador, and Venezuela (e.g., Anderson et al., 2002, 2003, 2012; Anderson and Jarrín-V., 2002; Anderson and Soriano, 1999; Cadena et al., 1998 Gómez-Laverde et al., 2004).  

Since 2005, I have maintained an active field program in Venezuela in close collaboration with Dr. Eliecer E. Gutierrez (see People), Dr. José Ochoa-G. and Dr. Marisol Aguilera.  We surveyed the Cerro Santa Ana and the Serranía de San Luis.  These isolated mountain ranges support evergreen cloud forest but are surrounded by a lowland matrix of dry thorn forests (see more pictures at the bottom of this page; Anderson et al., 2012).  To compare with these small isolated ranges, we conducted later fieldwork in the larger Cordillera de la Costa, in which then-undergraduate at CCNY Mariya Shcheglovitova (see People) participated.  See Evolution of Insular Faunas, above, for more information.

Beginning in 2010, Mariano Soley (see People) and I have mounted a field program in Costa Rica. We are focusing on highland sites, with the goal of studying comparative phylogeography and niche evolution of small non-volant mammals as part of Mariano's dissertation. CCNY then-undergraduate student Robert Boria (see People) participated in fieldwork with us during summer 2011.


Burro Burro River in Guyana and . . . . . . . . Field camp at Pakatau Falls, 1997;
see Lim et al., 1999

Cerro Santa Ana on the Península de Paraguaná in northwestern Venezuela (fieldwork undertaken in October 2005 in collaboration with Dr. José Ochoa-G.).

Laguna del Barva, Heredia, Costa Rica, July 2010. Photo by M. Soley


More photos from our field program in Venezuela:


Near the summit of Cerro Santa Ana, at a clear moment.


Dwarf cloud forest on Cerro Santa Ana.


Thorn forest near the base of Cerro Santa Ana.


Outline of Cerro Santa Ana in the distance, from northern slopes of the Serranía de San Luis.  Note the Istmo de los Médanos on the right, connecting the Península de Paraguaná to the rest of Venezuela.


Extensive stands of columnar cacti (cardonales) south of the Serranía de San Luis.


Thorn forest on the northern slopes of the Serranía de San Luis.


Cloud forest in the Serranía de San Luis.


Robert Anderson explains the differences between rodents and marsupials to young citizens of Santa Ana. Photographer unknown.


Dr. José Ochoa-G. (dark shirt, standing) shares information regarding our research and conservation of mammals and their environments to a crowd at the Casa de la Cultura, Santa Ana.


Lower: Carlos Valerio, Robert P. Anderson, Ruth Peña, Franger García; Upper: Simón Bolívar (bust). Santa Ana, Falcón, Venezuela. Photographer unknown.


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R. P. Anderson
Copyright © 2002-2015.

Unless noted, all photographs by RPA

Last modified: 30 April 2015 (RPA)