Putting insects on the map

Are the environmental causes for variation in species richness the same across all taxa?

Data resources used via GBIF : ~33,000 species occurrences
Bedstraw Hawk-moth (Hyles gallii)

Bedstraw Hawk-moth (Hyles gallii) caterpillar by Kjeld Brem. Photo via iNaturalist licensed under CC BY-NC 4.0.

The role of evolutionary and ecological mechanisms in driving species distributions is a core research topic in biodiversity science. New insights, however, tend to focus on vascular plants and vertebrates, even though invertebrates make up the clear majority of species on the planet. This paper concentrated on a group of herbivorous insects, the sphingid moths, and drew on GBIF and others to compute distributions model for 789 species found outside the Americas. The researchers used these to search for links between environment and species richness and found the greatest concentration of diversity in the moist tropics. This is matched by the observation that most species ranges are found in warm and wet areas with evapotranspiration being the strongest predictor of species richness. This contrasts with studies focused on terrestrial vertebrates, where temperature is the most important predictor of richness, highlighting the need to expand studies areas beyond these taxa.

Ballesteros-Mejia L, Kitching IJ, Jetz W and Beck J (2016) Putting insects on the map: near-global variation in sphingid moth richness along spatial and environmental gradients. Ecography. Wiley-Blackwell. Available at doi:10.1111/ecog.02438