Fig 1.
The system studied, phenotypes and population location sites.
(A) the three typical lizard phenotypes found on Scopolo, Capri and the mainland (from left to right); (B) spatial location and size of the Capri two islands (Capri and Scopolo islet) off the mainland; (C) geological dating of the origin of the two islands. RIS indicates the Reversed Island Syndrome that we described in previous work [23–25].
Table 1.
Genetic diversity observed in mainland and island (Capri and Scopolo) populations (complete mtDNA, 17,320 bp).
Fig 2.
Phylogenetic Bayesian tree of the all populations based on complete mitochondrial DNA sequences (A); coding regions (B) and noncoding regions (C). The tree was rooted using the mtGenome of Podarcis siculus from Sicily (accession number NC_011609). Bayesian posterior probabilities are indicated at nodes. Colours of subclades indicate populations from mainland (orange), Capri (green) and Scopolo (azure).
Fig 3.
Population tree inferred with *BEAST visualized using DensiTree [40].
All trees created in the analysis (except the burn-in phase) are displayed. Trees with the most common topology are highlighted in blue, trees with the second most common topology in red, trees with the third most common topology in pale green and all other trees in dark green. On the right, colours of subclades indicate populations from mainland (orange), Capri (green) and Scopolo (azure).
Fig 4.
Maximum clade probability tree displayed as a chronogram from the BEAST analysis of the mtGenome alignment.
All lineages evolved according to a strict clock and the HKY+G substitution model. Numbers above the nodes indicate phylogenetic support measures. Node bars illustrate the width of the 95% highest posterior density. Numbers indicate the posterior mean estimates of divergence times. On the right, colours of subclades indicate populations from mainland (orange), Capri (green) and Scopolo (azure).
Table 2.
McDonald-Kreitman test.
Fig 5.
Heatmap of differential gene expression between mainland lizards and island lizards.
Heatmap shows the expression of transcripts that were differentially expressed in mainland lizard brains (ML) and island lizard brains affected by RIS (SC). The heatmap gives a graphical representation of the expression level of the up and down regulated transcripts between Scopolo (SC) and mainland (ML) populations due to two the different environments. Each row corresponds to a transcript, and each column corresponds to a sample. Hierarchical clustering of differentially expressed transcripts (FDR < 0.001; FC>2) are shown from adult males of mainland (orange cluster) and Scopolo (azure cluster) specimens. Violet cells correspond to lower than average expression, and yellow cells correspond to higher than average expression.