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Population genetic studies are crucial for evolutionary biologists because the population is the basic substrate on which evolution is forged. However little empirical evidence has been able to demonstrate the role that isolation and gene flow play in maintaining differentiation in populations at short geographic scales. Epidalea calamita exhibits a steep variation in body size and reproductive traits in southwestern Spain, associated with changes in the geological substrate. This implies a decrease of 70.9% of body mass and 28.5% in snout-vent length, on a microgeographic scale of only 60 km. Previous results from both metamorphic and juvenile common garden experiments showed that genetic differentiation may be a causal determinant of geographic variation in adult. This study tested whether neutral genetic differentiation can explain the geographical variation in the body size observed in E. calamita. It was addressed analyzing the level of genetic structuring and gene flow among populations along the cline, comparing the genetic diversity between and within populations, as well as between ecological environments. The study showed that the geographic variation in body size observed in E. calamita has evolved in absence of geographic isolation, with moderate gene flow connecting the populations. Thus, neutral genetic differentiation cannot explain the geographical variation observed. Future studies are needed on the interaction between the genetic component with the environmental factors and will be necessary to analyze the contribution of the maternal effects in the origin and evolution of the geographical variation in the body size observed in E. calamita from southern Spain. [ABSTRACT FROM AUTHOR]

Alien predators are a major cause of decline and extinction of species worldwide, since native organisms are rarely equipped with specific antipredatory strategies to cope with them. However, phenotypic plasticity and learned predator recognition may help prey populations to survive novel predators. Here we examine geographical variation in the learning ability of larval spadefoot toads (Pelobates cultripes) to recognize invasive predatory crayfish (Procambarus clarkii). We compare the learning-mediated behavioural responses of tadpoles from six populations across two regions in Spain (central and southern), with different histories of exposure to the presence of the invasive species. Two of the populations showed innate recognition of chemical cues from the invasive crayfish, whereas three of them learned to recognize such cues as a threat after conditioning with conspecific alarm cues. Learning abilities did not differ among southern populations, but they did among central populations. We assessed patterns of genetic variation within and among these two regions through microsatellite markers and found low genetic divergence among the southern populations but greater differentiation among the central ones. We hypothesize that similar responses to the invasive crayfish in southern populations may have arisen from a combination of extended historical exposure to this introduced predator (~ 50 y) and higher levels of gene flow, as they inhabit a highly interconnected pond network. In contrast, populations from central Spain show lower connectivity, have been exposed to the invasive crayfish for a shorter period of time, and are more divergent in their plastic responses. [ABSTRACT FROM AUTHOR]

The genetic variation of the European population at a macro-geographic scale follows genetic gradients which reflect main migration events. However, less is known about factors affecting mating patterns at a micro-geographic scale. In this study we have analyzed 726,718 autosomal single nucleotide variants in 435 individuals from the catalan Pyrenees covering around 200 km of a vast and abrupt region in the north of the Iberian Peninsula, for which we have information about the geographic origin of all grand-parents and parents. At a macro-geographic scale, our analyses recapitulate the genetic gradient observed in Spain. However, we also identified the presence of micropopulation substructure among the sampled individuals. Such micropopulation substructure does not correlate with geographic barriers such as the expected by the orography of the considered region, but by the bishoprics present in the covered geographic area. These results support that, on top of main human migrations, long ongoing socio-cultural factors have also shaped the genetic diversity observed at rural populations. [ABSTRACT FROM AUTHOR]

This study aimed to detect different genotypes of Candida glabrata isolates in paediatric patients with and without neutropenia utilizing microsatellite length polymorphism (MLP) and its correlation with drug resistance and enzymatic activity were assessed. Samples from neutropenic and non‐neutropenic patients were collected from November 2020 to November 2021. Thirty‐six C. glabrata strains were isolated and identified using classical and molecular methods. Then, C. glabrata isolates were genotyped by the MLP technique, and their antifungal susceptibility was performed based on the CLSI M27 guideline. Eighteen different multi‐loci genotypes (G1–G18) were detected based on MLP analysis. Analysis of molecular variance revealed high genetic variation within populations (94%) and low genetic differentiation amongst populations (6%). Also, 40% (n = 4) of isolates from neutropenic patients were non‐wild‐type for posaconazole, and 30% (n = 3) were resistant to caspofungin. Very strong hemolytic and proteinase activity were seen in 97·2 and 86·1% of isolates. Candida glabrata strains from neutropenic patients were genetically divergent from other populations. The minimum spanning tree shows that observed genotypes were mainly related to previously reported genotypes from Iran, Spain, and China. [ABSTRACT FROM AUTHOR]

The intertidal snail Littorina saxatilis is well known for its remarkable variety of locally adapted populations. A unique L. saxatilis habitat is represented by the sheltered rocky environment found in the natural coastal lagoon of the Cíes Islands (NW Spain). The present-day characteristics of this habitat are relatively recent (~ 70–150 years), some of these have been human induced. In this study, we indirectly tested local adaptation resulting in ecotypic variation in this habitat by estimating the additive genetic differentiation between populations (QST) for morphological shell traits in families of embryos. We compared the Qst and Fst (AFLP loci) between populations of the previously described Crab ecotype (outside the lagoon) and the new Cíes lagoon ecotype (inside) as a proxy for adaptation. For several traits (RW1 and RW2; associated with a change in size of shell aperture) the QST was higher than corresponding FST, which indeed suggest that natural selection could be the force behind the apparent phenotypic divergence observed between the Crab and the Cíes lagoon ecotype. The putative process of local adaptation occurring in the Cíes lagoon ecotype (favoring a reduction of shell aperture) might be considered a case of fast phenotypic evolution driven by anthropogenic effects and with important conservation implications. Further genetic and ecological studies must be carried out to advance our knowledge in such an interesting system. [ABSTRACT FROM AUTHOR]

Abstract The rough periwinkle Littorina saxatilis is characterised for showing shell phenotypic variation associated to environmental clines and this is found in parallel across shores. In order to disentangle the additive genetic effects and the environmental factors involved in this variation, we analysed natural populations subjected to a gradient in wave exposure and crab predation in 3 different Rias (primary estuaries) from Galicia (NW Spain). In addition to previously described "Crab" and "Wave" ecotypes, we studied a new phenotype ("Crab+") associated to the most sheltered habitats of the gradient. We obtained estimates of heritability and Q st (between population genetic differentiation) in embryos and P st (between population phenotypic differentiation) in adults for shell morphology traits. Heritability estimates were close to one for shell size and relative shell aperture, suggesting a low impact of environmental factors in embryos. Estimates of Q st between ecotypes were significant and typically much higher than published F st estimates from neutral markers, indicating a role for selection on shaping additive genetic variation. Estimates of P st between ecotypes for adults were substantially larger than embryos´ Q st , suggesting also a role of phenotypic plasticity in ecotype differentiation. Our results suggest that P st vs F st comparisons should be taken with caution because they might not reflect real additive genetic effects, but P st vs Q st comparisons could shed light into the role of phenotypic plasticity. Highlights • Morphometric analysis of Littorina saxatilis is carried out in adults and embryos. • We compared phenotypic (P ST) and genetic divergence (Q ST , F ST) between ecotypes. • High heritabilities are shown for shell traits (size and shell aperture) in embryos. • Q ST vs F ST comparisons show a role for natural selection in ecotype differentiation. [ABSTRACT FROM AUTHOR]

• VIs revealed differences in needle phenology among Aleppo pine ecotypes. • P. halepensis sub-humid ecotypes showed earlier needle phenology. • Potential trade-offs between fire- and drought-related traits. • Lack of intra-specific differences in litter flammability of Aleppo pine. Pinus halepensis Mill. is a conifer typical of Mediterranean pinewoods adapted to drought and fire. Although the timing of seasonal events in P. halepensis is strongly associated with these stressors and other environmental factors, needle phenology and litter flammability are insufficiently characterized at the intraspecific level. These traits can be informative of the existence of locally adapted populations across the species' distribution range, and remote sensing approaches are promising tools to infer phenological changes in forest trees. In this study, we investigated intraspecific differentiation of P. halepensis related to needle phenology at the onset of the fire season (May-June) through vegetation indexes (VIs) obtained from unmanned aerial vehicles. We collected drone images using multispectral and RGB sensors for 56 adult populations of P. halepensis categorized into five ecotypes growing in two common gardens located in Spain under contrasting conditions (dry-continental versus wet-coastal). In the dry trial, we additionally monitored the temporal variation of RGB-derived indexes using two flights spaced over a one-month period. We also performed four consecutive ground measurements of needle pigments and fuel moisture content and obtained litter flammability traits for a subset of populations. Most in situ measurements and flammability traits did not show population differentiation. Regarding RGB-derived VIs, we did not detect obvious temporal patterns which differed among populations. However, we observed greener canopies in June than in May, which are indicative of the pace of current-year needle development. We also deduced an earlier phenology (i.e., earlier current-year needle unfolding) in the dry-continental trial. Ecotypic differentiation was found for some vegetation indexes related to needle unfolding (i.e., TCARI/OSAVI) and old needle senescence (i.e., PRSI). These differences were generally consistent across trials and time, and fundamentally indicated that sub-humid ecotypes typical of the eastern Mediterranean showed earlier needle unfolding and old needle senescence than semiarid ecotypes thriving in western continental Mediterranean areas. The intraspecific divergence observed in early season phenology is potentially related to the existence of contrasting life-history strategies present at the intraspecific level for the species. In particular, some semi-arid ecotypes, which are known to optimize the trade-off between carbon gain and water loss, exhibited an early old needle senescence (high likelihood of crown fire development) coupled with a late needle unfolding (conservative water use). These results indicate a possible trade-off between drought and fire resistance for the species, which suggest the importance of considering the intraspecific characteristics of Aleppo pine in forest management actions. [ABSTRACT FROM AUTHOR]

This survey reports the mitochondrial data of two Spanish populations living in the Vera and Bejar valleys, on the opposite slopes of the Sierra de Gredos (Central Spain), which crosses Spain east to west. The aim of the study was to characterise the mitochondrial genetic pool of the Vera and Bejar populations to investigate a putative mitogenetic differentiation between them, evidence that would support the role of the Sierra de Gredos as a genetic barrier in their micro-evolutionary histories. Blood samples of 137 people (66 from Vera and 71 from Bejar) were collected and mtDNA hypervariable regions I and II (HVR-I and HVR-II) were dissected along with several mtDNA-coding region SNPs. The main European mitochondrial lineages have been found both in Vera and in Bejar, together with the typical African haplogroups L (in Vera) and U6 (in Bejar). FST value and the 95% credible regions calculated for haplogroup frequencies do not reveal genetic differentiation among the populations. Vera and Bejar contain an expected mitochondrial variability within them, but they do not seem to be genetically different from each other, leading us to conclude that the Sierra de Gredos is not a significant genetic barrier in their maternal genetic history. [ABSTRACT FROM AUTHOR]

We have used PCR-RFLP analysis to screen ancestral and modern genetic variation of the mitochondrial ND1 region at eight Atlantic salmon rivers in northern Spain. Using old scales, we show that genetic variation in NW Spanish salmon populations has not changed significantly during the past 50 years. Comparing our data with that from the literature we can conclude that, in general, modern salmon populations from NW Spain are distinct from putative northern European donor populations. Taken together, these observations suggest that, despite the nonnative introductions carried out during 1970-1993, introgression of northern European mitochondrial genomes in NW Spanish salmon populations has been generally low. Different results were obtained for populations in NE Spain and southern France, where rivers Nansa, Asón, Bidasoa and Nive presented a high frequency of haplotypes characteristic of northern European rivers that reflect introgression. We show that the levels of introgression are correlated with the foreign stocking intensity. Thus, the rivers that were more intensely stocked are more similar to northern European salmon rivers. We also observed an East-West cline in the levels of foreign introductions and introgression. In addition, we provide the first description of the overall genetic structure of Atlantic salmon populations in southern Europe. We have observed evidences of genetic differentiation among populations and isolation by distance as a consequence of salmon homing behaviour. The results obtained do not call for changes in introduction policies in Spain, currently based on the use of native stocks. [ABSTRACT FROM AUTHOR]

• Flowering phenology in S. ciliata is genetically differentiated among populations. • Environmentally contrasted populations showed strong phenological differentiation. • Environmental differences were strong enough to generate past diversifying selection. • Populations plastically respond to temperature increase flowering earlier. • Early flowering may be an adaptive advantage to respond to ongoing climate change. Flowering phenology is an important life-history trait strongly influenced by the environment that directly affects plant fitness. Climate change is bringing about shifts in flowering time caused by adaptive evolution and phenotypic plasticity, but their relative contributions and effects are poorly understood. This is especially critical in Mediterranean alpine species, which experience steep environmental gradients at short distances characteristic of alpine environments and an intense summer drought period derived from the Mediterranean climate. Moreover, tracking climate change through migration to higher elevations is not always possible for alpine species since many already find their optimal niche at mountain summits. In this study, we aimed to determine if flowering phenology is genetically differentiated among populations inhabiting contrasting environmental conditions and ascertain if it has been subjected to past selection. This knowledge is crucial to understanding adaptation of alpine plants to current environmental gradients and to provide insight about what adaptations may be necessary to cope with future and ongoing climate warming. We used a common garden experiment to analyze genetic differentiation in phenological traits of nine populations of Silene ciliata Pourret (Caryophyllaceae) distributed at two environmentally differentiated areas (optimal and marginal habitat suitability) in three mountain ranges of Central Spain. Environmentally optimal areas for this species are close to the mountain tops, whereas marginal areas are found at the lower distribution edge. We also studied the relation between neutral genetic differentiation (F ST) and quantitative trait differentiation (P ST) to infer past selection on characters under contrasting environmental conditions. We found genetic differentiation for the onset, peak and end of flowering between populations in optimal and marginal areas in the presence of substantial gene flow. This finding highlights the strong diverging selection pressures between the different Mediterranean alpine environments. We also found evidence of past diversifying selection for flowering peak and end of flowering. This evidence of past adaptation in addition to adaptive phenotypic plasticity to advance flowering dates under warmer temperatures suggest that adaptation of flowering phenology to current and future warming should be feasible, especially for populations inhabiting optimal areas. [ABSTRACT FROM AUTHOR]

Information about the incidence and magnitude of local adaptation can help to predict the response of natural populations to a changing environment, and should be of particular interest in arctic and alpine environments where the effects of climate change are expected to be severe. To quantify adaptive differentiation in the arctic-alpine perennial herb Arabis alpina, we conducted reciprocal transplant experiments for 3 yr between Spanish and Scandinavian populations. At the sites of one Spanish and one Scandinavian population, we planted seedlings representing two Spanish and four Scandinavian populations, and recorded survival, flowering propensity and fecundity. The experiment was replicated in two subsequent years. The results demonstrate strong adaptive differentiation between A. alpina populations from the two regions. At the field site in Spain, survival and fruit production of Spanish populations were higher than those of Scandinavian populations, while the opposite was true at the site in Scandinavia, and these differences were consistent across years. By comparison, fitness varied little among populations from the same region. The results suggest that the magnitude and geographical scale of local adaptation need to be considered in predictions of the effects of global change on the dynamics of arctic and alpine plant populations., (© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.)

Dispersal and local patterns of adaptation play a major role on the ecological and evolutionary trajectory of natural populations. In this study, we employ a combination of genetic (25 microsatellite markers) and field-based information (seven study years) to analyse the impact of immigration and local patterns of adaptation in two nearby (<7 km) blue tit (Cyanistes caeruleus) populations. We used genetic assignment analyses to identify immigrant individuals and found that dispersal rate is female-biased (72%). Data on lifetime reproductive success indicated that immigrant females produced fewer local recruits than their philopatric counterparts whereas immigrant males recruited more offspring than those that remained in their natal location. In spite of the considerably higher immigration rates of females, our results indicate that, in absolute terms, their demographic and genetic impact in the receiving populations is lower than that in immigrant males. Immigrants often brought novel alleles into the studied populations and a high proportion of them were transmitted to their recruits, indicating that the genetic impact of immigrants is not ephemeral. Although only a few kilometres apart, the two study populations were genetically differentiated and showed strong divergence in different phenotypic and life-history traits. An almost absent inter-population dispersal, together with the fact that both populations receive immigrants from different source populations, is probably the main cause of the observed pattern of genetic differentiation. However, phenotypic differentiation (PST) for all the studied traits greatly exceeded neutral genetic differentiation (FST), indicating that divergent natural selection is the prevailing factor determining the evolutionary trajectory of these populations. Our study highlights the importance of integrating individual- and population-based approaches to obtain a comprehensive view about the role of dispersal and natural selection on structuring the genotypic and phenotypic characteristics of natural populations., (© 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.)