Authors: Outhwaite, Charlie; Newbold, Tim;

In recent years, several studies have investigated changes in insect biodiversity. Biodiversity changes are driven primarily by land-use change, and increasingly by climate change, but no study has assessed the effect of these drivers on insect biodiversity globally nor, importantly, the potential for interactions between these drivers. Here, we show that the interaction between rapid historical climate warming and intensive agricultural land use is associated with a reduction of almost 50% in abundance and of 27% in numbers of species within insect assemblages, compared to less-disturbed habitats with lower rates of historical climate warming. These patterns are particularly evident in the tropical realm, whereas some positive responses of biodiversity to climate change are seen in non-topical regions in natural habitats. Importantly, a high availability of nearby natural habitat often buffered the reductions in insect abundance and richness associated with agricultural land use and rapid climate change, but only in low-intensity agricultural systems. Our results show that insect biodiversity will likely benefit from mitigating climate change, preserving natural habitat within landscapes, and reducing the intensity of agriculture.