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A selective sweep is the result of strong positive selection driving newly occurring or standing genetic variants to fixation, and can dramatically alter the pattern and distribution of allelic diversity in a population. Population-level sequencing data have enabled discoveries of selective sweeps associated with genes involved in recent adaptations in many species. In contrast, much debate but little evidence addresses whether selfish genes are capable of fixation-thereby leaving signatures identical to classical selective sweeps-despite being neutral or deleterious to organismal fitness. We previously described R2d2, a large copy-number variant that causes nonrandom segregation of mouse Chromosome 2 in females due to meiotic drive. Here we show population-genetic data consistent with a selfish sweep driven by alleles of R2d2 with high copy number (R2d2(HC)) in natural populations. We replicate this finding in multiple closed breeding populations from six outbred backgrounds segregating for R2d2 alleles. We find that R2d2(HC) rapidly increases in frequency, and in most cases becomes fixed in significantly fewer generations than can be explained by genetic drift. R2d2(HC) is also associated with significantly reduced litter sizes in heterozygous mothers, making it a true selfish allele. Our data provide direct evidence of populations actively undergoing selfish sweeps, and demonstrate that meiotic drive can rapidly alter the genomic landscape in favor of mutations with neutral or even negative effects on overall Darwinian fitness. Further study will reveal the incidence of selfish sweeps, and will elucidate the relative contributions of selfish genes, adaptation and genetic drift to evolution.

Conservation research and policies tend to be significantly restricted wherever relevant data on biodiversity is sparse, scattered or non-curated. Thus, the usefulness of occurrence data, for the study of biodiversity, depends not only on the availability but also on data quality. Notwithstanding the increase in the global availability of primary biodiversity data, they have numerous shortfalls, from incomplete or partially erroneous documentation to spatial and temporal biases (Hortal et al. 2015, Aubry et al. 2017). Also, many non-digitized specimen collections, scientific publications and grey literature are locked as printed or digital publications. We integrated existing knowledge, from dispersed sources of biodiversity data, namely Global Biodiversity Information Facility (GBIF), natural history collections, wildlife survey reports, species checklist and other scientific literature. This procedure allowed an update of Mozambique's checklist of terrestrial mammals (Neves et al. 2018). Despite the potential from digital data to overcome gaps of knowledge, a relevant constraint on creating or updating species checklist is the dificulty to access spatially-disperse collections and examine every specimens upon which occurrences are based. To partly overcome this impediment, we developed a species selection process for specimen data from GBIF and museums (Fig. 1). The aim was to categorise the species detected in more than one data source as species with the well-supported occurrence. In addition to the number of collectors, we also accounted for the number of records collected and presented in Smithers and Tello (1976), the last checklist produced for Mozambique' mammals. A species-occurrence record was considered well-supported and included into the species checklist when was: 1. independently recorded by different collectors or 2. recorded by a single collector but listed in Smithers and Tello (1976). An additional list was produced which contained species with questionable occurrence in the country. Species entered this "questionable occurrence" list when they were: 1. not listed in Smithers and Tello (1976), and a single record supported its presence in the country; 2. not listed in Smithers and Tello (1976) and multiple records exist, but were all cited by a single author; or 3. registered with a single record in Smithers and Tello (1976). We compiled more than 17000 records, resulting in a total of 217 species (14 orders, 39 families and 133 genera) with supported occurrence in Mozambique and 23 species with questionable reported occurrence (Table 1). The proposed approach for species selection can be adapted and function as a powerful tool to update species checklists of countries facing similar lack of knowledge regarding their biodiversity. The capacity to pinpointing species and specimens in need of occurrence and taxonomic re-evaluation is of great value to optimise collection's study and to boost collaboration between curators and researchers. Lastly, considering that most records integrated are from European and North American institutions, this work would significantly improve with the integration of data from African institutions. Therefore, an effort should be made to make these essential collections accessible online. [ABSTRACT FROM AUTHOR]

Despite the rise of the global availability of biodiversity data by digitisation, essential regions of the world remain poorly documented (Peterson et al. 2015). Research-neglected regions that lack quality information, are mainly the species-rich and developing nations (Gaikwad and Chavan 2006). Mozambique is an African country without a wide-ranging knowledge regarding its fauna's diversity and distribution (Neves et al. 2018). Undeniably, this country's knowledge gaps constitute a significant impediment for the improvement of effective conservation measures. Primary species occurrence data across dispersed data sources can be a cost-effective resource for boosting knowledge about a country's biodiversity. Aiming to aggregate a comprehensive dataset of Mozambique's terrestrial mammals, we compiled primary species occurrence data from dispersed data sources. The produced dataset not only gathered digitalised accessible knowledge (DAK) from the Global Biodiversity Information Facility (GBIF) and natural history collections, but also retrieved and digitalised species occurrence data enclosed in grey and scientific literature. Particularly for poorly documented countries, filling data gaps are crucial for new and broad insights for biodiversity research and preservation. Thus, quantification of the effects of data digitisation and mobilisation goes beyond the specific goals of organisations, institutions or data-sharing resources. The impact of data digitisation should be disseminated, not only by the number of publications and times data are accessed (Nelson and Ellis 2018), but also by the actual achievements in regions covered by DAK. To highlight the impact of further data digitisation in a poorly documented country, we examine the effective gain of further digitisation and data cleaning on the terrestrial mammals from Mozambique. We demonstrate the increase in the overall knowledge, not merely in terms of number of species, number of records, and country's coverage, but from the production of outputs with potential value for data-driven conservation research and planning. More than 17000 records were compiled. The digitisation of data in literature as well as data cleaning and quality improvements resulted in a substantial increase in the amount of DAK, which acknowledges Mozambique's high species diversity (Fig. 1). The digitisation and data mobilisation hereby described allowed for the update of the country's terrestrial mammals checklist (Neves et al. 2018). The final dataset also expands the knowledge of the most poorly documented provinces, allowing generation of a data-driven proposal of priority areas to survey (in review). Also, an assessment of Mozambique's conservation network effectiveness for mammal protection was performed, and additional relevant areas were suggested (in prep.). The dataset compiled is an important "stepping stone" towards an enhanced knowledge of Mozambique's fauna. Biodiversity conservation and management in developing countries rich in natural resources, which often must deal with a lack of internal capacity for applied research and conservation actions, are challenges. Considering that digitisation and mobilisation of biodiversity data are resourceful processes for improving knowledge collaborative work between institutions of those countries and international data-provider communities could, in the short term, successfully improve the information baseline to support decision-making in future conservation and management actions. [ABSTRACT FROM AUTHOR]

Objective: In this study, the behavioral and physiological changes induced by experimentally varying the risk of predation in male mice fed a high-fat diet were examined. In particular, the study aimed to assess whether the risk of being predated modulates the body weight gain, providing an ecological context for the obesity resistance observed in many species of small mammals.Methods: Body weight, food intake, physical activity, and core body temperature of 35 male C57BL/6 mice were monitored for 20 days, while feeding a high-fat diet. A third of the animals were exposed to elevated risk of predation through exposure to the sounds of nocturnal predatory birds, and these were compared to animals exposed to a neutral noise or silence.Results: Male mice exposed to predation risk had significantly lower weight gain than the neutral or silent groups. Reduced food intake and increased physical activity were the main proximal factors explaining this effect. The risk of predation also induced changes in boldness.Conclusions: This study provides evidence supporting the role of predation risk on body weight gain of small mammals. [ABSTRACT FROM AUTHOR]

This study investigated geno- and cyto-toxic damage in the free-living rodent, Mus spretus after exposure to a simulated spill of crude oil on soil. The results revealed increased mutagenicity and cytotoxicity in bone marrow cells and increased DNA damage in blood cells. Exposure to crude oil increased sperm abnormalities, with lasso-like folds being the most common. These results point to the value of this rodent in serving as a sentinel species for the monitoring and prediction of environmental hazards. [ABSTRACT FROM AUTHOR]

The house mouse, Mus musculus, is one of the most ubiquitous invasive species worldwide and in Australia is particularly common and widespread, but where it originally came from is still unknown. Here we investigated this origin through a phylogeographic analysis of mitochondrial DNA sequences (D-loop) comparing mouse populations from Australia with those from the likely regional source area in Western Europe. Our results agree with human historical associations, showing a strong link between Australia and the British Isles. This outcome is of intrinsic and applied interest and helps to validate the colonization history of mice as a proxy for human settlement history. [ABSTRACT FROM AUTHOR]

Theory predicts that when maladaptive hybridization occurs assortative mating preference should evolve. Moreover, habitat characteristics can influence quality of mates that is an important criterion in mate choice. Here we ask how chromosomal compatibility and differences in habitat quality might shape preference for odors of the opposite sex in the house mouse. Our study model is composed of 2 chromosomal races and their narrow hybrid zone that occur in habitats of different qualities. We performed 2-way choice tests during which opposite sex urine mixtures of each race were presented to mice from the 2 races and the hybrid zone. Differential investigation of the odor sources indicated both preference and that the odors differed. The results show that the 2 races carry distinct odors and, irrespective of the race they belonged to, males preferred odors of females from the race occurring in habitats of lower quality (hereafter, race B), whereas females preferred odors of males from the race occurring in habitats of better quality (hereafter, race A). Further, preference in the hybrid zone was for race B odors, which differed significantly from that displayed by the 2 races (i.e., for race A odors). The relative influences of geography, ecology, and chromosomal compatibility are discussed, thus leading us to propose that habitat differences might play the most important role in shaping signal divergence and preference in this system. [ABSTRACT FROM PUBLISHER]

The Cabrera vole is an endangered species frequently found in the montado, a savannah-like ecosystem well adapted to fire. Although it is assumed that regular burning is not very prejudicial to this vole, the impact of fire is unknown. This research studied, for the first time, recolonisation by the Cabrera vole after wildfire. Colonies were monitored over one year after a wildfire and the most relevant ecological features in their reestablishment were identified. During the first eight months, all the 18 surveyed colonies remained unoccupied. However, after one year, II were recolonised. Vegetation structure and composition in the colonies (vegetation height, plant families diversity, percentage of bare ground and cover of shrubs before the fire), which are important features in offering protection and nutrition, were closely related to reoccupation of the colonies. Surprisingly, fire intensity did not influence recolonisation. Distance from unburned areas proved to be a factor that delayed recolonisation. The importance of the montado for this species was reinforced by the evidence that recolonisation occurred preferentially in colonies surrounded by this habitat type. [ABSTRACT FROM AUTHOR]

The Cabrera vole ( Microtus cabrerae) is a threatened rodent endemic in the Iberian Peninsula with a patchy distribution and specific microhabitat requirements. This aim of this study was to document the composition of plant communities in habitats of Cabrera vole colonies in southern Portugal. Differences observed in plant species composition were also compared with vegetation structure, taxonomic and life form groups, species and group diversity, disturbance, topography and soil properties. Vegetation was sampled between March and July 2004, in 26 colonies occurring in five geographical areas. Grasses were the most abundant, common and diverse family in the colonies, and the perennial grass Agrostis castellana was present in 92% of colonies, with a mean cover of 16% of the site. Other frequently occurring species were Briza maxima (85%), Vulpia myuros (85%), Gaudinia fragilis (81%), Leontodon spp. (81%), Avena barbata (77%), Bromus hordeaceus (77%) and Tolpis barbata (77%). Colonies were classified in eight vegetation groups that included meadows, tall perennial grasslands, manured meadows with tall sedges, annual grasslands and ruderal and nitrophilous grasslands. Main gradients associated with composition differences were grass richness, annual and perennial grass cover, vegetation structure (herbaceous vegetation height), soil properties (texture and moisture), disturbance (ruderal species) and colony dimensions (area). Results suggest that the Cabrera vole is able to exploit a wide variety of grasslands, with a varying degree of ecological disturbance. Meadows and perennial grassland communities seem to be higher-quality microhabitats for voles. [ABSTRACT FROM AUTHOR]

In mammals, the zona pellucida glycoprotein 3 (ZP3) is considered a primary sperm receptor of the oocyte and is hypothesized to be involved in reproductive isolation. We investigated patterns of diversity and selection in the putative sperm-binding region (pSBR) of mouse ZP3 across Cricetidae and Murinae, two hyperdiverse taxonomic groups within muroid rodents. In murines, the pSBR is fairly conserved, in particular the serine-rich stretch containing the glycosylation sites proposed as essential for sperm binding. In contrast, cricetid amino acid sequences of the pSBR were much more variable and the serine-rich motif, typical of murines, was generally substantially modified. Overall, our results suggest a general lack of species specificity of the pSBR across the two muroid families. We document statistical evidence of positive selection acting on exons 6 and 7 of ZP3 and identified several amino acid sites that are likely targets of selection, with most positively selected sites falling within or adjacent to the pSBR. [ABSTRACT FROM AUTHOR]

Heavy metals accumulation in parallel with the evaluation of physiological and biochemical effects resulting from continued metal exposure were considered here using for the first time the great white-toothed shrew Crocidura russula as an in vivo model. Shrews were originated from an abandoned lead/zinc mining area and from a reference area, both in Alentejo, southern Portugal. Hepatic contents of nickel, copper, zinc, cadmium, mercury and lead were quantified by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). Haematological parameters (white blood cells, red blood cells, haemoglobin and haematocrit) were obtained in a Coulter Counter Analyser and biochemical markers of the redox balance (glutathione S-transferase, glutathione peroxidase, and glutathione reductase) activities were measured spectrophotometrically using a Duo-50 spectrophotometer. Compared with control animals, significantly higher concentration of hepatic cadmium (9. 29 vs. 1. 18 μg/g dry weight) and nickel (1. 56 vs. 0. 343 μg/g dry weight) were detected in the shrews collected in the mining area. However, no significant changes were observed on haematological or enzymatic parameters in animals exposed to metal pollution. The obtained results show that shrews are good bioaccumulators of toxic heavy metals, but very tolerant to their effects, revealing an interesting long-term adaptation to polluted environments. In addition, this study provides reference values for haematological parameters and antioxidant enzymes levels in C. Russula, which may be relevant for comparative purposes in further studies. [Copyright &y& Elsevier]

Hepatic and renal concentrations of iron, magnesium, zinc, lead, copper, manganese, mercury, cadmium, molybdenum, chromium, and nickel were quantified in shrews (Crocidura russula) inhabiting a pyrite mine site in Portugal. Several morphological parameters (body weight, residual index, and relative weights) were also examined to clarify the physiological effects of pollution. Shrews from the mine showed increased bioavailability of Fe, Pb, Hg, Cd, Mo, and Ni in comparison with reference specimens. Adult shrews had the highest Cd levels while Cr and Ni concentrations diminished. Intersexual differences were found for Mo and Ni. As a consequence of metal pollution, the relative hepatic weight was higher in shrews from the mine site when compared with reference specimens. These data indicate that C. russula is a good bioindicator of metal pollution. We also evaluated the toxic effects of Pb, Hg, Cd, and Ni, because several shrews from the polluted site showed high concentrations of these metals. To approximate at the real biological impact of abandoned mines, after this first step it is necessary to associate the bioaccumulation levels and morphological effects with other physiological, ecological and genetical biomarkers. [Copyright &y& Elsevier]

Voles of the genus Microtus represent one of the most speciose mammalian genera in the Holarctic. We established a molecular phylogeny for Microtus to resolve contentious issues of systematic relationships and evolutionary history in this genus. A total of 81 specimens representing ten Microtus species endemic to Europe as well as eight Eurasian, six Asian and one Holarctic species were sequenced for the entire cytochrome b gene (1140bp). A further 25 sequences were retrieved from GenBank, providing data on an additional 23, mainly Nearctic, Microtus species. Phylogenetic analysis of these 48 species generated four well-supported monophyletic lineages. The genus Chionomys, snow voles, formed a distinct and well-supported lineage separate from the genus Microtus. The subgenus Microtus formed the strongest supported lineage with two sublineages displaying a close relationship between the arvalis species group (common voles) and the socialis species group (social voles). Monophyly of the Palearctic pitymyid voles, subgenus Terricola, was supported, and this subgenus was also subdivided into two monophyletic species groups. Together, these groupings clarify long-standing taxonomic uncertainties in Microtus. In addition, the “Asian” and the Nearctic lineages reported previously were identified although the latter group was not supported. However, relationships among the main Microtus branches were not resolved, suggesting a rapid and potentially simultaneous radiation of a widespread ancestor early in the history of the genus. This and subsequent radiations discernible in the cytochrome b phylogeny, show the considerable potential of Microtus for analysis of historical and ecological determinants of speciation in small mammals. It is evident that speciation is an ongoing process in the genus and that the molecular data provides a vital insight into current species limits as well as cladogenic events of the past. [Copyright &y& Elsevier]

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications., (© 2022 The Authors. Ecology © 2022 The Ecological Society of America.)

Heavy metal mining is one of the largest sources of environmental pollution. The analysis of different types of biomarkers in sentinel species living in contaminated areas provides a measure of the degree of the ecological impact of pollution and is thus a valuable tool for human and environmental risk assessments. In previous studies we found that specimens from two populations of the Algerian mice (Mus spretus) living in two abandoned heavy metal mines (Aljustrel and Preguiça, Portugal) had higher body burdens of heavy metals, which led to alterations in enzymatic activities and in haematological, histological and genotoxic parameters, than mice from a nearby reference population. We have now analysed individuals from the same sites at the biometric and genetic levels to get a broader portrayal of the impact of heavy metal pollution on biodiversity, from molecules to populations. Size and shape variations of the mouse mandible were searched by implementing the geometric morphometric method. Population genetic differentiation and diversity parameters (φST estimates; nucleotide and haplotype diversities) were studied using the mitochondrial cytochrome b gene (Cytb) and the control region (CR). The morphometric analyses revealed that animals from the three sites differed significantly in the shape of the mandible, but mandibular shape varied in a more resembling way within individuals of both mine sites, which is highly suggestive for an effect of environmental quality on normal development pathways in Algerian mice. Also, antisymmetry in mandible size and shape was detected in all populations, making these traits not reliable indicators of developmental instability. Overall little genetic differentiation was found among the three populations, although pairwise φST comparisons revealed that the Aljustrel and the Preguiça populations were each differentiated from the other two populations in Cytb and in CR, respectively. Genetic diversity parameters revealed higher genetic diversity for Cytb in the population from Aljustrel, while in the population from Preguiça diversity of the two markers changed in opposite directions, higher genetic diversity in CR and lower in Cytb, compared to the reference population. Demographic changes and increased mutation rates may explain these findings. We show that developmental patterns and genetic composition of wild populations of a small mammal can be affected by chronic heavy metal exposure within a relatively short time. Anthropogenic stress may thus influence the evolutionary path of natural populations, with largely unpredictable ecological costs., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The potential use of metallothioneins (MTs) as biomarkers of trace metal contamination was evaluated for the first time in the Algerian mouse (Mus spretus). Mice were collected seasonally in an abandoned mining area (Aljustrel) and in a reference area, both located in southern Portugal. MT levels were quantified in liver and kidney by differential pulse polarography and hepatic elemental concentrations (Mn, Fe, Cu, Zn, Se) were determined by particle-induced X-ray emission. Hepatic iron and selenium concentrations were elevated in mice from Aljustrel mine when compared to reference animals. MTs levels were averagely higher in mice from Aljustrel than those originated from the reference area. A season-dependent significant effect was found on the hepatic and renal MT concentrations, characterized by higher levels in winter and lower in autumn. In contaminated mice positive relationship between liver elemental contents (Cu in autumn and Fe in winter) and MTs were found. The seasonal variation of MT suggests that probably physiological and environmental factors could influence hepatic and renal MT induction. Results seem to imply that some environmental disturbance occur in the vicinity of the Aljustrel mine. Therefore, for the management purposes MT levels should be followed in liver of M. spretus, especially in winter. Furthermore, other physiological factors that could influence MT expression and turnover in Algerian mouse should also be monitored.