Our research interests comprise a broad array of topics related to the fields of macroecology, biogeography, community and theoretical ecology, ecophylogenetics, phylogenetic comparative methods and conservation biology. We are particularly interested in studying geographic patterns of biodiversity and the structure of ecological communities as well as understanding the causes that originate, maintain and alter such patterns. We focus mainly on vertebrates, especially mammals, but have work with other taxa including amphibians and birds, and currently have projects involving insects and plants. Currently, we integrate ecological and evolutionary approaches to study biogeographic and phylogenetic patterns, their relationship with the environment and the application of such studies to informed conservation assessments and actions.
I am interested in all things "macroecological". Macroecology is a synthetic research program that seeks to understand the emergent, statistical properties of complex ecological systems (e.g. ecological communities, complete biotas, biodiversity patterns) at broad spatial and temporal scales. I'm particularly interested in macroecological research owing to its integration between ecology and biogeography, considering processes at different scales, in order to explain geographic biodiversity patterns. Under this research program, I have described and evaluated species richness gradients considering the inherent relationship between diversity and distribution. Such a relationship is a direct consequence of how diversity is established: not all the species are distributed everywhere, hence different regions have different sets of species (i.e. differential distribution among species and diversity among sites). Therefore, a comprehensive analysis of geographic biodiversity patterns should include site-based and species-based approaches. My PhD research was dedicated to study this diversity-distribution relationship (e.g. Villalobos 2014; Villalobos and Arita 2010; Villalobos et al. 2014). From then on, I have focused mainly on the species-based approach, trying to understand the structure of geographic ranges and the co-occurrence among species to explain geographic gradients of diversity. Nevertheless, I continue to investigate "traditional" macroecological patterns such as those looking at richness differences among regions and relating them to the environment and history of such regions (e.g. Gouveia, Villalobos et al. 2014; Arita, Vargas and Villalobos 2014). Most macroecological research requires large amounts of data and particular tools to handle and analyze such data. In order to help in this endeavour, I also continuously work in collaboration with other colleagues (specially Bruno Vilela) to develop and contribute useful tools for conducting macroecological research (please, see the 'R' tab of this webpage).
One of the aims of biodiversity science is to produce studies that can help mitigate the current biodiversity crisis and contribute to the conservation of biological diversity. Owing to the intrinsic relationship between the two basic properties of biodiversity, diversity and distribution, and their obvious relevance to conservation, my research also has an applied component. Accordingly, I try to implement macroecological analyses to the context of conservation planning, namely, the designation of priority sites for conservation. Relevant sites for conservation are usually defined in an "either or" fashion based on richness, endemicity or threat. However, these definitions usually result in different sets of sites that are spatially non-congruent. This one-dimensional view of conservation priority setting may not bring us closer to our general goal of preserving biodiversity. This is why I favor a more comprehensive view of conservation where we take into account both diversity and distribution simultaneously to define priority sites for conservation (e.g. Villalobos et al. 2013. Biological Conservation; Villalobos et al. 2013. PLoS ONE). I continue to work collaboratively on projects related to conservation biogeography, specially from a macroecological and macroevolutionary perspective that can help us identify patterns and processes of imprtance to preserve the standing biological diversity we observe today (e.g. Vilela, Villalobos et al. 2014).
Ecological communities have particular structures regarding species richness, composition, morphological and phylogenetic arrangement, etc. I'm interested in studying what causes such communities to have particular structures. One particular issue that interest me is the use of morphological and taxonomic/phylogenetic information to describe and evaluate community structure (e.g. Ortiz-Ramirez and Villalobos 2011; Villalobos and Arita 2014). Such information can be useful to inform us about potential causal processes that otherwise would be very hard (if not practically imposible) to test (e.g. biotic interactions, niche filtering, stochastic assembly, etc.). I usually study ecological communities in a geographical context, considering different spatial scales, the geographical structure of data (e.g. spatial autocorrelation), and different facets of biodiversity (e.g. functional, phylogenetic, turnover (beta diversity), nestedness, etc.). Most of my work on communities has been with bats but I have also started to work with other vertebrate groups and plants including their herbivore insect faunas (Grandez-Rios et al. Accepted; Moura et al. In prep).
Large-scale patterns of biodiversity are determined by the interplay between ecological and evolutionary processes. These latter processes are thought to be more influential owing to the inherent historical dynamics that result in such patterns. Therefore, an evolutionary perspective is now considered fundamental in macroecological research (Diniz-Filho et al. 2013. Frontiers of Biogeography). I have tried to include such a perspective in my research, specially regarding the species-based approach mentioned above. For instance, I've been studying the phylogenetic structure of geographic co-occurrence among species (e.g. Villalobos et al. 2013) in order to consider species' histories that may inform us on the processes behind diversity gradients. In the same vein, species' histories can also be assess with the use of paleontological information. I'm currently working on this "paleontological macroecology" (Diniz-Filho et al. 2013) approach, using fossils to study the temporal dynamics of geogrpahic biodiversity patterns. In fact, most of my current research involves, in one way or another, the use of phylogenetic/historical information to study different macroecological and macroevolutionary questions such as what drives geographic differences in species richness and richness differences among clades (several works submitted or in prep.). To conduct this research, I commonly apply phylogenetic comparative methods (see below) that explicitly take into account species' histories and try to identify evolutionary processes determining different aspects of biodiversity.
Owing to their shared ancestry, species cannot be considered as independent observations. In fact, there is a tendency of closely related species to be more similar among each other than to other, distantly related species. As a consequence, interspecific comparisons must explicitly consider species' evolutionary history in order to avoid statistical biases. As a way to take into account such non-independence among species, different phylogenetic comparative methods (PCMs) have been developed. Considering the evolutionary aspect of my research and the interspecific component of most of the patterns I study, I commonly apply PCMs into my studies. I'm particularly interested in explicitly considering phylogenetic information in my research, thus the use of PCMs becomes fundamental, whether to avoid wrong statistical estimates or to model evolutionary processes that may be responsible for biodiversity patterns. Lately, I have been involved in the application, testing, and development of different PCMs to understand the tempo and mode of evolutionary and macroecological patterns (e.g. Bini, Villalobos and Diniz-Filho 2014. Ecosistemas; Diniz-Filho, Villalobos and Bini. Accepted. Genetics and Molecular Biology; Diniz-Filho, Alves, Villalobos et al. 2015. Journal of Evolutionary Biology; and several works submitted or in prep.).