Elverici, C. | bioRxiv Science

bioRxiv2023

Predicting climate-driven distribution shifts in Hyalomma marginatum (Ixodidae)

Hyalomma marginatum is an important tick species which is the main vector of Crimean-Congo haemorrhagic fever (CCHF) and spotted fever. The species is predominantly distributed in parts of Southern Europe, North Africa and West Asia. However, due to ongoing climate change and increasing reports of H. marginatum in central and northern Europe, the expansion of this range poses a potential future risk. In this study, we employed an Ecological Niche Modelling (ENM) approach to model the current and future climatic suitability of H. marginatum. Using high resolution climatic variables from the Chelsa dataset and an updated list of locations for H. marginatum, we constructed 2 models under current environmental conditions using MaxEnt: a more specific model for only current conditions, and a more general model for both current conditions and future projections under the ssp370 and ssp585 scenarios. Our models show that the climatically suitable region for H. marginatum matches the current distributional area in the Mediterranean basin and West Asia. When applied to future projections, our models suggest a considerable expansion of H. marginatums range in the north in Europe as a result of rising temperatures. However, they also predict a decline in central Anatolia, potentially due to the exacerbation of drought conditions in that region. SubjectsEcology, Entomology, Epidemiology, Infectious Diseases, Climate Change Biology

ecology↗

bioRxiv2022

Historical Demography and Climate Driven Range Shifts in the Blue-spotted Salamander Under the Climate Change Scenarios

AO_SCPLOWBSTRACTC_SCPLOWThis study integrates phylogeography with distributional analysis to understand the demographic history and range dynamics of a limited dispersal capacity amphibian species, Blue-spotted Salamander (Ambystoma laterale), under several climate change scenarios. For this we used an ecological niche modeling approach, together with Bayesian based demographic analysis, to develop inferences regarding this species demographic history and range dynamics. The current model output was mostly congruent with the present distribution of the Blue-spotted Salamander. However, under both the Last Interglacial and the Last Glacial Maximum bioclimatic conditions, the model predicted a substantially narrower distribution than the present. These predictions showed almost no suitable area in the current distribution range of the species during almost the last 22.000 y before present (ybp). The predictions indicated that the distribution of this species shifted from eastern coast of northern North America to the southern part of the current distribution range of the species. The Bayesian Skyline Plot analysis, which provided good resolution of the effective population size changes over the Blue-spotted Salamander history, was mostly congruent with ecological niche modeling predictions for this species. This study provides the first investigation of the Blue-spotted Salamanders late-Quaternary history based on ecological niche modeling and Bayesian-based demographic analysis. In terms of the main result of this study, we found that the species present genetic structure has been substantially affected by past climate changes, and this species has reached current distribution range almost from nothing since the Last Glacial Maximum.

evolutionary biology↗