Niche modelling and correlation analyses of climate variables

In this work, we explore the impact of demography and biogeographic history in ecological niche model interpretations, examining the potential of integrating genetic and ecological methodologies in elucidating the evolutionary dynamics of the geographic ranges of cryptic species. We conducted intensive sampling across the Iberian Peninsula to obtain mtDNA phylogeographic data, and develop fine-scale climate models for the cryptic earwigs Forficula dentata and F. mediterranea. The phylogeographic patterns revealed divergent evolutionary histories: F. dentata exhibited a well-established, geographically structured lineage, while F. mediterranea displayed a star-shape pattern typical of recent expansion. Comparison of current climate models and those projected into the past and future, indicate that F. dentata, seems to be facing a substantial reduction in its suitable habitat due to ongoing climate change, and potentially exacerbated by interaction with F. mediterranea. Our results show that climatic factors alone cannot determine the distribution of the two species. Historical and demographic factors are crucial in shaping their current geographical structure. Nonetheless, we cannot overlook the potential influence of ongoing climatic changes. Exploring the intricate interplay between historic, genetic and distribution is opening a new way to validate the predictions of climate models and to decipher contradictory emerging signals.