My main research aim is to determine why is biodiversity – and in particular community structure – geographically distributed in the way it is, and to identify the processes that domain the spatial and temporal dynamics of ecological assemblages. Given the temporal dimension of biogeographical dynamics, I use approaches based on both recent and paleontological data – sometimes in combination with phylogenetic information – as well as theoretical models. Although I am specialized in dung beetles, I work with many different taxa – including other insects, vertebrates, seed plants, brypohytes, or even microorganisms – often at large spatial scales.
I am particularly interested in the origin of the geographic patterns of biodiversity. Here I study how historical factors that operate at regional scales – both past climate changes and evolutionary processes such as extinction or geographic isolation – have an impact on current diversity gradients. I also study how the influence of these factors and current climate varies according to the spatial and temporal scale. Thus, in this area I work at global, continental and regional scales, as well as in different archipelagos; many of my works refer to either continental Europe or the Macaronesian archipelagos (including the Azores and the Canary Islands). My current work aims at unifying into a single framework the different hypotheses about the origin geographic gradients of biodiversity; in particular, the effects of the evolutionary history of species, glaciations and current climate.
A closely related area of research is the organization of biological communities in time and space. Here I have the long-term aim of developing a general framework for community ecology and biogeography, which would integrate all the processes that generate geographic patterns of biodiversity. To do this I work on two main areas: the origin and evolution of island biotas – using theoretical models and empirical data on both the islands and their pools of colonizers; and on the geographical and local determinants of the ecological structure of communities – working with species traits, phylogenies, and recently ecological interaction networks. Apart from the organisms I’m specialized in, here I’ve also started to work on how do biogeographical principles apply to microscopic organisms, in order to explore the possibility of using communities of some of these organisms for experiments in biogeography and ecology of communities that are impossible to achieve at larger scales.
A less theoretical line of research – though quite important to study biodiversity in the real world – is the measurement of biological diversity and the biases associated with biodiversity data. My extensive activity in this topic may be grouped into four main themes. The first two are closely related: (i) the development and exploitation of biological databases – where I’ve worked for GBIF and the ATLANTIS databases of Canaries, Azores and Madeira; and (ii) the problems and biases on the data available in these databases – including how to identify bias in historical information about the distribution of biodiversity, determine the reliability of the picture of diversity and species’ ecology provided by such information, and design surveys to cover these deficiencies. In this area I am currently working (in collaboration with other researchers) in the development of maps of the uncertainty in data on the distribution of biodiversity. But I’m not reduced to identify the limitations in the data; I also work on the best way to overcome them and take advantage of biodiversity information for scientific use and conservation assessment. Here I have worked on (iii) the development and evaluation of biodiversity estimators and surrogates – including species richness, dissimilarity and environmental indicators. And I work extensively on (iv) the theoretical needs and limitations of predictive models of the geographic distribution of both species and attributes of biodiversity – such as richness or composition. Although this is a secondary area of research for me (so I rarely lead scientific works), I work regularly in this area, mainly in seeking a more rational use of Species Distribution Models based on solid theoretical foundations.
Finally, as biodiversity research is currently a ‘science of crisis’, I also work on practical applications for conservation and management of biodiversity. In the past I worked on Systematic Conservation Planning and selection of areas for conservation, but I rarely do it now. What I continue to do is to collaborate with researchers on the use of geographical approaches to conservation issues, such as assessing the risk of spread of invasive species, the eventual shifts in species distributions caused by climate change, or determining the ‘extinction debt’ that the historical reduction of native habitats may have on the species endemic to oceanic archipelagos.