Insect functional traits across varying landscape and latitudinal gradients

Landscape simplification is known to affect the abundance and diversity of insects worldwide. These anthropogenically driven shifts in land cover are particularly well-studied in the case of pollinators and have been identified as one of the drivers of pollinator decline. Recent evidence shows that landscape simplification also affects insect traits, frequently causing a decrease in body size within pollinator species. Landscape simplification occurs worldwide and here we hypothesize that its effect on insect traits interacts with latitudinal gradient, varying from the tropics to the more temperate regions of the world. Given that tropical regions host a higher biodiversity ,we predict that the negative effects of landscape simplification are more stable in tropical than temperate regions. Our meta-analysis compiled body size data on insects from both agricultural and natural landscapes, provided by over 50 collaborators worldwide. Here we present our findings on pollinator body size changes across both a land use and latitudinal gradient. We find that as landscapes simplify, in tropical regions insects show increasing body size. On the contrary in temperate regions, this pattern flips – and we see that as landscapes simplify, insects show decreasing body size. These results show that our understanding of how landscape simplification affects pollinator communities and populations might be skewed towards temperate regions and that a better understanding of the interaction between landscape and latitudinal gradients is required to better understand patterns of landscape simplification worldwide.