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Intra- and inter-specific gene flow are natural evolutionary processes. However, human-induced hybridization is a global conservation concern across taxa, and the development of discriminant genetic markers to differentiate among gene flow processes is essential. Wolves (Canis lupus) are affected by hybridization, particularly in southern Europe, where ongoing recolonization of historic ranges is augmenting gene flow among divergent populations. Our aim was to provide diagnostic canid markers focused on the long-divergent Iberian, Italian and Dinaric wolf populations, based on existing genomic resources. We used 158 canid samples to select a panel of highly informative single nucleotide polymorphisms (SNPs) to (i) distinguish wolves in the three regions from domestic dogs (C. l. familiaris) and golden jackals (C. aureus), and (ii) identify their first two hybrid generations. The resulting 192 SNPs correctly identified the five canid groups, all simulated first-generation (F1) hybrids (0.482 ≤ Qi ≤ 0.512 between their respective parental groups) and all first backcross (BC1) individuals (0.723 ≤ Qi ≤ 0.827 to parental groups). An assay design and test with invasive and non-invasive canid samples performed successfully for 178 SNPs. By separating natural population admixture from inter-specific hybridization, our reduced panel can help advance evolutionary research, monitoring, and timely conservation management. [ABSTRACT FROM AUTHOR]

Context: Landscape genetics focuses on quantifying relationships between landscape features and gene flow. Most past landscape genetic studies have addressed relationships between landscape structure and genetic differentiation in single study areas. However, failure to investigate multiple areas across a species range could produce misleading inferences about which landscape variables generally limit gene flow in a given species resulting in faulty management decisions. Objectives: The main objectives of this paper were to identify the landscape features that facilitate or impede stone marten gene flow across its Iberian range, and to test whether gene flow is always influenced by the same set of landscape features or if they are detected only when they are limiting in a particular landscape. Methods: We conducted an individual-based meta-replicated landscape genetic analysis using multivariate-restricted optimization with reciprocal causal modeling in three study areas within the Iberian Peninsula with strongly contrasting landscape characteristics. Results: Variables explaining the stone marten distribution differed among areas, confirming that relationships between genetic connectivity and landscape features are variable across Iberia. We found clear patterns in which variables were included in the final optimized model related to how limiting those variables were to gene flow in each particular study area. Conclusions: This study highlights that variability in limiting factors can have a large effect on predictions of which landscape features affect gene flow. Our results suggest that landscape models specific to the region of interest should be developed before proposing management and conservation actions, and contribute to the growing understanding of limiting factors in landscape genetics. [ABSTRACT FROM AUTHOR]

Coherent ecological networks (EN) composed of core areas linked by ecological corridors are being developed worldwide with the goal of promoting landscape connectivity and biodiversity conservation. However, empirical assessment of the performance of EN designs is critical to evaluate the utility of these networks to mitigate effects of habitat loss and fragmentation. Landscape genetics provides a particularly valuable framework to address the question of functional connectivity by providing a direct means to investigate the effects of landscape structure on gene flow. The goals of this study are (1) to evaluate the landscape features that drive gene flow of an EN target species (European pine marten), and (2) evaluate the optimality of a regional EN design in providing connectivity for this species within the Basque Country (North Spain). Using partial Mantel tests in a reciprocal causal modeling framework we competed 59 alternative models, including isolation by distance and the regional EN. Our analysis indicated that the regional EN was among the most supported resistance models for the pine marten, but was not the best supported model. Gene flow of pine marten in northern Spain is facilitated by natural vegetation, and is resisted by anthropogenic landcover types and roads. Our results suggest that the regional EN design being implemented in the Basque Country will effectively facilitate gene flow of forest dwelling species at regional scale. [ABSTRACT FROM AUTHOR]