Understanding how environmental factors influence the distribution of species richness is important for predicting future impacts of climate change on biodiversity. One way that we can attempt to quantify such patterns is through gradients, such as elevation gradients. Elevation gradients are important for maintaining and generating biodiversity, and due to their high turnover in environmental conditions, serve as an ideal study system to investigate what environmental factors affect species composition. Despite this, the global trend in species richness of the most diverse group of animals, the insects, with elevation is unknown. The current evidence is variable across studies, with patterns of decreasing, increasing, and mid-elevation peaks in species richness with elevation. Moreover, most studies are from single-systems, different regions, different taxa, and use different sampling techniques. A global synthesis across systems is needed to provide a better understanding of how insect species richness changes with elevation, and the environmental factors underlying those patterns. We compare insect species richness patterns across over 100 elevation gradients from 74 published studies to ask: how does insect species richness change with elevation, and do these patterns differ with location or taxon? Preliminary results suggest that there is no consistent pattern across all insects, and variable results are found across taxa and region. These findings suggest that there is no universal way to predict insect species diversity across elevation, and reinforces that site-level data will be needed to make accurate predictions about how climate change will affect individual systems.
