Paso doble: A two-step Late Pleistocene range expansion in the Tyrrhenian tree frog Hyla sarda

First brain de-novo transcriptome of Tyrrenhian tree frog, Hyla sarda, for the study of dispersal-related behavioral variation

“…According to previous phylogeographic studies, H. sarda underwent a northward range expansion from the north of Sardinia (western Mediterranean sea) during the last glacial phase (Spadavecchia et al, 2021). The colonization of the Corsica island was allowed by the temporary formation of a wide land bridge connecting Sardinia and Corsica, induced by the marine regression occurred during the last glacial maximum (Bisconti et al, 2011a, b; Spadavecchia et al, 2021). The postglacial loss of this land bridge prevented any subsequent gene flow between Corsican and Sardinian populations.…”

“…The Tyrrhenian tree frog Hyla sarda (De Betta, 1853) is a small amphibian endemic to the Tyrrhenian islands. According to previous phylogeographic studies, H. sarda underwent a northward range expansion from the north of Sardinia (western Mediterranean sea) during the last glacial phase (Spadavecchia et al, 2021). The colonization of the Corsica island was allowed by the temporary formation of a wide land bridge connecting Sardinia and Corsica, induced by the marine regression occurred during the last glacial maximum (Bisconti et al, 2011a, b;Spadavecchia et al, 2021).…”

Spatial differentiation of background matching strategies along a Late Pleistocene range expansion route

“…A total of 154 individuals were collected from 4 geographic areas, arranged along the inferred Late Pleistocene range expansion route of H. sarda (Spadavecchia et al, 2021; see Figure 1 and Table S1). Previous analyses of the bioclimatic niche of H. sarda carried out under both current and periglacial bioclimatic conditions, suggested spatially and temporally homogeneous habitat suitability models along the eastern coast (Bisconti et al, 2011b).…”

“…sarda is a tree frog endemic to the Tyrrhenian Islands (Western Mediterranean), whose evolutionary history was characterised by a major northward range expansion during the last glacial phase (Bisconti et al, 2011a, b; Spadavecchia et al, 2021). This tree frog colonised the northern portion of its current range (Corsica island and the Tuscan archipelago) from an ancestral area located along the central-eastern coast of Sardinia, taking advantage of a temporary land-bridge connection between Corsica and Sardinia (Spadavecchia et al, 2021). However, this land bridge was lost during the postglacial sea-level rise, preventing subsequent gene exchange between the source (Sardinian) and the newly colonised (Corsican) populations (Spadavecchia et al, 2021).…”

“…This tree frog colonised the northern portion of its current range (Corsica island and the Tuscan archipelago) from an ancestral area located along the central-eastern coast of Sardinia, taking advantage of a temporary land-bridge connection between Corsica and Sardinia (Spadavecchia et al, 2021). However, this land bridge was lost during the postglacial sea-level rise, preventing subsequent gene exchange between the source (Sardinian) and the newly colonised (Corsican) populations (Spadavecchia et al, 2021).…”