Environmental data sets matter in ecological niche modelling: an example with Solenopsis invicta and Solenopsis richteri

Aim In response to a recent paper suggesting the failure of ecological niche models to predict between native and introduced distributional areas of fire ants (Solenopsis invicta), we sought to assess methodological causes of this failure. Location Ecological niche models were developed on the species' native distributional area in South America, and projected globally. Methods We developed ecological niche models based on six different environmental data sets, and compared their respective abilities to anticipate the North American invasive distributional area of the species. Results We show that models based on the 'bioclimatic variables' of the WorldClim data set indeed fail to predict the full invasive potential of the species, but that models based on four other data sets could predict this potential correctly. Main conclusions The difference in predictive abilities appears to centre on the complexity of the environmental variables involved. These results emphasize important influences of environmental data sets on the generality and ability of ecological niche models to anticipate novel phenomena, and offer a simpler explanation for the lack of predictive ability among native and invaded distributional areas than that of niche shifts.