Evidences for a shared history for spectacled salamanders, haplotypes and climate

Area of Science:

• Ecology
• Evolutionary Biology
• Biogeography

Background:

• Pleistocene climatic oscillations shaped European species distribution through glacial refugia, migrations, and population isolation.
• The ancient amphibian genus Salamandrina, now endemic to peninsular Italy, likely survived Miocene climatic shifts in the Apennines.
• Two parapatric species, Salamandrina perspicillata and S. terdigitata, currently inhabit Italy and share a secondary contact zone post-Last Glacial Maximum.

Purpose of the Study:

• To directly measure climate influences on the distribution of Salamandrina perspicillata and S. terdigitata.
• To integrate genetic data with climate modeling to understand past and present species distributions.
• To identify glacial refugia and post-glacial recolonization corridors for these endemic salamanders.

Main Methods:

• Ensemble Modelling techniques were employed to simulate climate influences.
• Geographic Information System (GIS) analyses were used for post-modelling spatial assessments.
• Updated genetic data were integrated with climate and distribution models.

Main Results:

• Climate was confirmed as a key factor influencing the distribution of Salamandrina species.
• Hypotheses regarding southwards and subsequent northwards species shifts were supported.
• Specific glacial refugia and corridors utilized during post-glacial recolonization were identified.

Conclusions:

• The study successfully mapped climate-driven distribution shifts and identified critical refugia and corridors for Salamandrina.
• A contact zone with observed introgression and hybridization requires further sampling to fully understand.
• Climate modeling provides crucial insights into the evolutionary history and future distribution of European amphibians.