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The study of colour, including physical properties and patterns, is an essential step in comprehensively understanding the role, evolution and diversification of this trait involved in functions like survival, performance, reproductive success and communication. While quantitative studies on colour have primarily focused on colour attributes, such as hue or brightness, the quantitative assessment of how colours are distributed across an organism's body (i.e. pattern) has received less attention despite its high functionality irrespective and together with colour. This gap is particularly noticeable in amphibians, especially in highly polymorphic, continuously variable species. In this study, we use the urodele Salamandra salamandra as a study model to apply an analytical approach for extracting and quantifying colour proportions and patterns variation using the recently developed R packages patternize and recolorize to precisely describe and compare colour distribution at both taxonomic and habitat levels. We first assessed the potential application of this workflow in taxonomic studies by examining its accuracy and sensitivity in differentiating morphs, using S. s. bernardezi and S. s. gallaica subspecies. Subsequently, we applied the same analytical approach to compare colour and colour pattern shifts among population of S. s. bernardezi within an urban–forest system. Our results demonstrated that this methodological workflow effectively detects differences in colour patterns at the taxonomic and habitat levels, confirming its utility in different fields, from systematics to eco‐evolutionary studies. Furthermore, our results revealed an increased prevalence of melanistic colouration and a less homogeneous colour pattern within urban settings, contributing to the limited number of studies about amphibian colouration in anthropic habitats. We outline and discuss alternative hypotheses to explain these patterns, although further investigation is necessary to address several new questions that arise from our results. [ABSTRACT FROM AUTHOR]

Tropical montane taxa are often locally adapted to very specific climatic conditions, contributing to their lower dispersal potential across complex landscapes. Climate and landscape features in montane regions affect population genetic structure in predictable ways, yet few empirical studies quantify the effects of both factors in shaping genetic structure of montane-adapted taxa. Here, we considered temporal and spatial variability in climate to explain contemporary genetic differentiation between populations of the montane salamander, Pseudoeurycea leprosa. Specifically, we used ecological niche modelling ( ENM) and measured spatial connectivity and gene flow (using both mt DNA and microsatellite markers) across extant populations of P. leprosa in the Trans- Mexican Volcanic Belt ( TVB). Our results indicate significant spatial and genetic isolation among populations, but we cannot distinguish between isolation by distance over time or current landscape barriers as mechanisms shaping population genetic divergences. Combining ecological niche modelling, spatial connectivity analyses, and historical and contemporary genetic signatures from different classes of genetic markers allows for inference of historical evolutionary processes and predictions of the impacts future climate change will have on the genetic diversity of montane taxa with low dispersal rates. Pseudoeurycea leprosa is one montane species among many endemic to this region and thus is a case study for the continued persistence of spatially and genetically isolated populations in the highly biodiverse TVB of central Mexico. [ABSTRACT FROM AUTHOR]

Abstract: Phylogeographic studies during the last decade confirmed an internal complexity of the Iberian Peninsula and northern Maghreb as refugial areas during the Miocene to Pleistocene period. Species with low vagility that experienced the complex climatic and palaeogeographic processes occurred in the Western Mediterranean Basin are excellent candidates to study the extent of lineage diversification in this region. We applied phylogenetic analyses based on mitochondrial data to infer the evolutionary history of Vipera latastei/monticola and identify the major biogeographic events structuring the genetic diversity within this group. We obtained a well-resolved phylogeny, with four highly divergent lineages (one African and three Iberian) that originated in the Tertiary. Coalescence-based estimations suggest that the differentiation of the four major lineages in V. latastei/monticola corresponds to the Messinian salinity crisis and the reopening of the Strait of Gibraltar during the Miocene. Subsequent Pliocene and Pleistocene climatic oscillations continued to isolate both Iberian and Maghrebian populations and led to a high genetic structuring in this group, particularly in Southern Iberia, a complex palaeogeographic and topographic region with high endemism levels. This study does not support the current taxonomy of the group, thus suggesting that an integrative evaluation of Iberian and African populations is needed to resolve its systematics. [Copyright &y& Elsevier]

Continental islands offer an excellent opportunity to investigate adaptive processes and to time microevolutionary changes that precede macroevolutionary events. We performed a population genetic study of the fire salamander (Salamandra salamandra), a species that displays unique intraspecific diversity of reproductive strategies, to address the microevolutionary processes leading to phenotypic and genetic differentiation of island, coastal and interior populations. We used eight microsatellite markers to estimate genetic diversity, population structure and demographic parameters in viviparous insular populations and ovoviviparous coastal and interior populations. Our results show considerable genetic differentiation (FST range: 0.06-0.27), and no clear signs of gene flow among populations, except between the large and admixed interior populations. We find no support for island colonization by rafting or intentional/accidental anthropogenic introductions, indicating that rising sea levels were responsible for isolation of the island populations approximately 9000 years ago. Our study provides evidence of rapid genetic differentiation between island and coastal populations, and rapid evolution of viviparity driven by climatic selective pressures on island populations, geographic isolation with genetic drift, or a combination of these factors. Studies of these viviparous island populations in early stages of divergence help us better understand the microevolutionary processes involved in rapid phenotypic shifts. [ABSTRACT FROM AUTHOR]

Species that contain populations with different reproductive modes offer excellent opportunities to study the transition between such strategies. Salamandra salamandra (Linnaeus, 1758) is one of two species within the Salamandra– Lyciasalamandra clade which displays two reproductive modes simultaneously. Along the S. salamandra distribution, the common reproductive mode is ovoviviparity although the species also has viviparous populations in the northern Iberian Peninsula. The occurrence of viviparity has recently been reported in two small offshore island populations on the Atlantic coast (NW Iberia), which originated after the last glacial period (8000–9000 years ago). In this paper, we analysed ovoviviparous, hybrid and viviparous populations (inland and mainland) from 17 localities across the northern Iberian Peninsula using two mitochondrial markers (Cyt b and COI, c. 1100 bp). Phylogenetic and phylogeographic analyses highly support that viviparity arose as an evolutionary novelty in the S. salamandra island populations and that viviparous populations are therefore not monophyletic. The recent insularity of Atlantic island populations leads us to conclude that the transition from ovoviviparity to viviparity can happen in a very short-time span. Additionally, to determine the likely source of this evolutionary transition, we discuss how ecological pressures could have an effect on the maintenance of the ovoviviparous reproductive mode. Hence, taking into account the results of this study, we propose the consideration of the island populations as an evolutionary unit for conservation purposes. [ABSTRACT FROM AUTHOR]