The invasions paradox
Why can alien species succeed in environments to which they have had no opportunity to adapt and even become more abundant than many native species? Ecological theory suggests two main possible answers for this paradox: competitive superiority of exotic species over native species and opportunistic use of ecological opportunities derived from human activities. We investigate these hypotheses in birds combining comparative studies, field observations and experiments in birds and mammals.
Behavioural responses to environmental changes
Confronted with alterations in their environment, animals can avoid extinction through the development of behavioural adjustments. A growing body of evidence suggests that behavioural flexibility, whether in the form of innovation or learning, can help animals survive in novel environments, for example by enabling them to find appropriate food resources or to develop responses to novel predators. Despite the progress, there are two major questions that are insufficiently understood: (1) What is the function of learning in the relationship of animals with their environment? And (2) What are the consequences of behavioural flexibility in the response to habitat destruction or climate changes. We address these two questions using an integrative approach that combines experiments and comparative analyses in birds.
Impact of urbanization on Earth's biota
Urbanization has become one of the most important components of the current global environmental change, contributing to a general impoverishment of biodiversity and favouring biotic homogenization. Although animal diversity and abundance are altered radically in urban ecosystems relative to wildlands, the underlying reasons remain obscure. We ask how urbanization alters natural communities with comparative analyses of birds along urbanization gradients.
Behaviour, niche evolution and adaptive diversification
The behaviour of animals is a factor which can change the course of their evolution, since it exposes individuals to new selection forces. However, its role in the processes of diversification has rarely been validated empirically and the mechanisms involved are still the subject of intense debate. This lack of knowledge is paradoxical, since behaviour is regarded as central to classic models of evolution such as adaptive radiation, geographic speciation and the origin of polymorphisms. We address these issues with phylogenetic comparative analyses in birds and Columbiformes.