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The Mediterranean Basin is a global biodiversity hotspot, hosting a number of native species belonging to families that are found almost exclusively in tropical climates. Yet, whether or not these taxa were able to survive in the Mediterranean region during the Quaternary climatic oscillations remains unknown. Focusing on the European free‐tailed bat (Tadarida teniotis), we aimed to (a) identify potential ancient populations and glacial refugia; (b) determine the post‐glacial colonization routes across the Mediterranean; and (c) evaluate current population structure and demography. Mitochondrial and nuclear markers were used to understand T. teniotis evolutionary and demographic history. We show that T. teniotis is likely restricted to the Western Palearctic, with mitochondrial phylogeny suggesting a split between an Anatolian/Middle East clade and a European clade. Nuclear data pointed to three genetic populations, one of which is an isolated and highly differentiated group in the Canary Islands, another distributed across Iberia, Morocco, and France, and a third stretching from Italy to the east, with admixture following a pattern of isolation by distance. Evolutionary and demographic reconstruction supports a pre‐Last Glacial Maximum (LGM) colonization of Italy and the Anatolian/Middle East, while the remaining populations were colonized from Italy after the Younger Dryas. We also found support for demographic expansion following the Iberian colonization. The results show that during the LGM T. teniotis persisted in Mediterranean refugia and has subsequently expanded to its current circum‐Mediterranean range. Our findings raise questions regarding the physiological and ecological traits that enabled species with tropical affinities to survive in colder climates. [ABSTRACT FROM AUTHOR]

Abstract: The interaction between agricultural production and wildlife can shape, and even condition, the functioning of both systems. In this study, we i) explored the degree to which a widespread European bat, namely the common bent‐wing bat Miniopterus schreibersii, consumes crop‐damaging insects at a continental scale, and ii) tested whether its dietary niche is shaped by the extension and type of agricultural fields. We employed a dual‐primer DNA metabarcoding approach to characterize arthropod 16S and COI DNA sequences within bat faecal pellets collected across 16 Southern European localities, to first characterize the bat species’ dietary niche, second measure the incidence of agricultural pests across their ranges and third assess whether geographical dietary variation responds to climatic, landscape diversity, agriculture type and vegetation productivity factors. We detected 12 arthropod orders, among which lepidopterans were predominant. We identified >200 species, 44 of which are known to cause agricultural damage. Pest species were detected at all but one sampling site and in 94% of the analysed samples. Furthermore, the dietary diversity of M. schreibersii exhibited a negative linear relation with the area of intensive agricultural fields, thus suggesting crops restrict the dietary niche of bats to prey taxa associated with agricultural production within their foraging range. Overall, our results imply that M. schreibersii might be a valuable asset for biological pest suppression in a variety of agricultural productions and highlight the dynamic interplay between wildlife and agricultural systems. [ABSTRACT FROM AUTHOR]

Abstract: Metabarcoding of environmental samples has many challenges and limitations that require carefully considered laboratory and analysis workflows to ensure reliable results. We explore how decisions regarding study design, laboratory set‐up, and bioinformatic processing affect the final results, and provide guidelines for reliable study of environmental samples. We evaluate the performance of four primer sets targeting COI and 16S regions characterizing arthropod diversity in bat faecal samples, and investigate how metabarcoding results are affected by parameters including: (1) number of PCR replicates per sample, (2) sequencing depth, (3) PCR replicate processing strategy (i.e. either additively, by combining the sequences obtained from the PCR replicates, or restrictively, by only retaining sequences that occur in multiple PCR replicates for each sample), (4) minimum copy number for sequences to be retained, (5) chimera removal, and (6) similarity thresholds for Operational Taxonomic Unit (OTU) clustering. Lastly, we measure within‐ and between‐taxa dissimilarities when using sequences from public databases to determine the most appropriate thresholds for OTU clustering and taxonomy assignment. Our results show that the use of multiple primer sets reduces taxonomic biases and increases taxonomic coverage. Taxonomic profiles resulting from each primer set are principally affected by how many PCR replicates are carried out per sample and how sequences are filtered across them, the sequence copy number threshold and the OTU clustering threshold. We also report considerable diversity differences between PCR replicates from each sample. Sequencing depth increases the dissimilarity between PCR replicates unless the bioinformatic strategies to remove allegedly artefactual sequences are adjusted according to the number of analysed sequences. Finally, we show that the appropriate identity thresholds for OTU clustering and taxonomy assignment differ between markers. Metabarcoding of complex environmental samples ideally requires (1) investigation of whether more than one primer sets targeting the same taxonomic group is needed to offset primer biases, (2) more than one PCR replicate per sample, (3) bioinformatic processing of sequences that balance diversity detection with removal of artefactual sequences, and (4) empirical selection of OTU clustering and taxonomy assignment thresholds tailored to each marker and the obtained taxa. [ABSTRACT FROM AUTHOR]

Aim We used an integrative approach to reconstruct the evolutionary history of the alpine long-eared bat, Plecotus macrobullaris, to test whether the variable effects of Pleistocene climatic oscillations across geographical regions led to contrasting population-level demographic histories within a single species. Location The Western Palaearctic. Methods We sequenced the complete mitochondrial genomes of 57 individuals from across the distribution of the species. The analysis integrated ecological niche modelling ( ENM), approximate Bayesian computation ( ABC), measures of genetic diversity and Bayesian phylogenetic methods. Results We identified two deep lineages: a western lineage, restricted to the Pyrenees and the Alps, and an eastern lineage, which expanded across the mountain ranges east of the Dinarides (Croatia). ENM projections of past conditions predicted that climatic suitability was reduced during cold stages in the areas inhabited by the western lineage, while the opposite trend was observed in the mountains inhabited by the eastern lineage. The palaeodemographic scenario that best fitted our data is consistent with the western lineage population size having shrunk repeatedly because of the extensive glaciation events that occurred in the Alps and Pyrenees during the Pleistocene. In contrast, the eastern lineage maintained a constant population size as is consistent with more limited glaciation in the mountains of south-eastern Europe and the Middle East. Main conclusions This study shows that the demographic response of populations to Pleistocene climatic oscillations depended on their geographical location, offering an example of population-level variations in the effects and long-term consequences of climate change. [ABSTRACT FROM AUTHOR]