Le séminaire de Rafael de Camargo est ANNULE.

Lieu: Brunoy

Abstract: Habitat loss is consider one of the major threats to biodiversity worldwide. In terrestrial ecosystems, natural land covers (e.g., forest) are, to a first approximation, regarded as essential habitats to protect biodiversity. I have tested several predictions on the general hypothesis that species’ ecological responses (i.e., richness) depend upon forest covers (and other landscape features). Applying landscape- and macro-ecology approaches I have deeply investigated how, and by how much, land covers and their configurations affect species richness at the landscape-level and across large extents in Eastern North America and worldwide. Overall, I have found that 1) forest cover amounts per se poorly explain the variance of species’ ecological responses at the landscape level. However models predictability may improve when land covers are better defined; 2) Habitat fragmentation is overstated as prejudicial to species’ prevalence; 3) the relationship between natural land cover and species diversity is dependent of scale, geographical regions, and data-sampling methods. I have argued that the prevalent assumption that habitat loss leads to species loss has become a panchreston. It may be misguiding conservation biology strategies by focusing on a threat that is too general to be usefully predictive.