Search

Endotherms vary widely in their capacity to defend sublethal body temperature (Tb) during acute heat exposure. Interspecific variation in the upper thermal limits of small mammals remains poorly studied, particularly in taxa other than bats. We hypothesised that rupicolous elephant shrews (Macroscelidae), on account of their occupancy of above-ground rock crevices in hot habitats and rapid cursorial locomotion, have evolved pronounced heat tolerance capacities. To test this hypothesis, we quantified relationships between Tb, resting metabolic rate (RMR) and evaporative water loss (EWL) in western rock elephant shrews (Elephantulus rupestris) exposed to air temperature (Tair) approaching or exceeding Tb under conditions of low humidity representative of the study population's arid, winter-rainfall habitat in western South Africa. Our data revealed a pronounced capacity to tolerate Tair > Tb, with E. rupestris tolerating Tair up to 48.0 ± 0.1 °C while defending Tb > 7 °C below Tair (maximum Tb = 41.64 ± 0.16 °C). Three behavioural pathways were employed to dissipate heat: open mouth panting, flattening their body posture, and nose-licking. At the highest experimental Tair values achieved, EWL increased 15.05-fold relative to normothermic levels and heat was dissipated evaporatively at rates equivalent to 174%—240% of metabolic heat production. The heat tolerance limit of Tair = 48 °C in E. rupestris is one of the highest yet recorded in a non-volant small mammal, and our data support the notion that elephant shrews possess a pronounced capacity to avoid lethal hyperthermia during acute heat exposure. [ABSTRACT FROM AUTHOR]

Borna disease virus 1 (BoDV-1) is the causative agent of Borna disease, a fatal neurologic disorder of domestic mammals and humans, resulting from spill-over infection from its natural reservoir host, the bicolored white-toothed shrew (Crocidura leucodon). The known BoDV-1-endemic area is remarkably restricted to parts of Germany, Austria, Switzerland and Liechtenstein. To gain comprehensive data on its occurrence, we analysed diagnostic material from suspected BoDV-1-induced encephalitis cases based on clinical and/or histopathological diagnosis. BoDV-1 infection was confirmed by RT-qPCR in 207 domestic mammals, 28 humans and seven wild shrews. Thereby, this study markedly raises the number of published laboratory-confirmed human BoDV-1 infections and provides a first comprehensive summary. Generation of 136 new BoDV-1 genome sequences from animals and humans facilitated an in-depth phylogeographic analysis, allowing for the definition of risk areas for zoonotic BoDV-1 transmission and facilitating the assessment of geographical infection sources. Consistent with the low mobility of its reservoir host, BoDV-1 sequences showed a remarkable geographic association, with individual phylogenetic clades occupying distinct areas. The closest genetic relatives of most human-derived BoDV-1 sequences were located at distances of less than 40 km, indicating that spill-over transmission from the natural reservoir usually occurs in the patient´s home region. Borna disease virus 1 (BoDV-1) is a zoonotic pathogen endemic in bicoloured white-toothed shrews in Central Europe that can cause fatal encephalitis in humans and other mammals. Here, the authors investigate the molecular epidemiology and phylogeography of BoDV-1 using newly collected and archived samples. [ABSTRACT FROM AUTHOR]

The article discusses the potential of using tree shrews as a preferred animal model for studying nephrolithiasis, a disease characterized by kidney stone formation. Tree shrews share similarities with primates in tissue anatomy, physiology, and immune responses, making them valuable for biomedical research. The study compared the efficacy of inducing kidney stones in tree shrews, rats, and mice, with tree shrews showing promising results. The findings suggest that tree shrews could be a suitable surrogate animal for investigating kidney stone disease due to their model effectiveness and resemblance to primate characteristics. [Extracted from the article]

Humans and other animals readily transition from externally to internally focused attention, and these transitions are accompanied by activation of the default mode network (DMN). The DMN was considered a cortical network, yet recent evidence suggests subcortical structures are also involved. We investigated the role of ventral pallidum (VP) and mediodorsal thalamus (MD) in DMN regulation in tree shrew, a close relative of primates. Electrophysiology and deep learning-based classification of behavioral states revealed gamma oscillations in VP and MD coordinated with gamma in anterior cingulate (AC) cortex during DMN states. Cross-frequency coupling between gamma and delta oscillations was higher during DMN than other behaviors, underscoring the engagement of MD, VP and AC. Our findings highlight the importance of VP and MD in DMN regulation, extend homologies in DMN regulation among mammals, and underline the importance of thalamus and basal forebrain to the regulation of DMN. A study using electrophysiology, behavioral methods and modelling demonstrates the importance of the ventral pallidum and mediodorsal thalamus in DMN regulation in tree shrews. [ABSTRACT FROM AUTHOR]

In 2010–2023, the dynamics of the population abundance and changes in the proportion of species in the community of small mammals (insectivores and rodents) inhabiting a slope larch forest in the vicinity of the city of Magadan (northern coast of the Sea of Okhotsk) was traced. The census of animals was carried out using Gero traps and cone traps (trap-line methods). In total, we analyzed 4700 trap-nights and 15 720 cone-nights. Altogether, 3384 individuals of 9 species belonging to the families of shrews (Soricidae), squirrels (Sciuridae), mice (Muridae), and hamsters (Cricetidae) were trapped. During the considered period, the relative abundance and the amplitude of its interannual fluctuations decreased in the populations of even-toothed shrews (Sorex isodon) and grey red-backed voles (Craseomys rufocanus). The proportion of Laxmann's shrews (S. caecutiens) and Korean field mice (Apodemus peninsulae) in the community increased 2.6 and 2.5 times, respectively, while the proportion of even-toothed shrew and grey red-backed vole decreased 2.8 times and 3 times, respectively. As a result, about 50% of the individuals in the samples were Laxmann's shrews and about 30% were northern red-backed voles (Clethrionomys rutilus). This, in turn, led to an increase in the dominance (the Simpson index increased from 0.21 to 0.34), a decrease in evenness (the Pielou index decreased from 0.87 to 0.61), and a significant decrease in the species diversity of the small mammal community (the Shannon index decreased from 1.7 to 1.3; t = 10.90, p < 0.001). [ABSTRACT FROM AUTHOR]

Nucleotide sequence polymorphism and haplotypic diversity of the cytochrome b gene were studied in samples of the Laxmann's Shrew subspecies-Sorex caecutiens koreni from the populations of the Kolyma River basin and Chukotka Peninsula. Fifty-six cytb haplotypes differing among themselves by 87 mutations in 84 sites were found. The cytb haplotypes of individuals of the subspecies S. c. koreni and S. c. macropygmaeus were shown to belong to the same maternal mtDNA lineage; their monophyletic origin from the same ancestral haplotype Scb1 and the presence of identical cytb haplotypes in both subspecies were revealed. The mutual isolation of the shrew populations in the upper basin of the Kolyma River and Chukotka is shown. The proportion of intrapopulation genetic variability is 95.74%, intergroup variability is 5.74%, and intragroup variability is 1.48%, which reflects a very high level of intrapopulation variability of cytb haplotypes in the studied groups of S. c. koreni, their monophyletic origin, and the genetic unity of the Chukchi samples. The values of molecular diversity indices testify to the stability of populations that have had a high value of effective abundance for a long time. [ABSTRACT FROM AUTHOR]

Semi-fossorial Sorex unguiculatus is a common shrew species in the central part of Northeast Asia, and this paper is devoted to elucidating its status in shrew taxocenes within the entire specified range. The configuration of the modern range of the long-clawed shrew differs from the generally accepted one, and its formation occurred through distribution from two Late Pleistocene refugiums—mainland and island. According to the status of the long-clawed shrew in the taxocenes, three areas were distinguished: this species is a dominant in low-species insular taxocenes, a subdominant in multispecies taxocenes of coniferous–broad-leaved forests of the Ussuri Territory, and a minor one in the zone of interpenetration of nemoral and taiga vegetation of the left-bank part of the Lower Amur Region. The further northwestern expansion of the long-clawed shrew is unlikely due to the specific requirements of this species for the type and structure of soils, which change significantly under the conditions of the appearance of permafrost, and coexistence with an ecologically similar species—the flat-skulled shrew. [ABSTRACT FROM AUTHOR]

An analysis of the community of rodents and insectivores in five biotopes of the southern forest steppe of Northern Kulunda has been carried out. High biodiversity is typical for the coastal strip with dense herbage near the lake, and low biodiversity is typical for the feather grass–forb steppe. At the beginning of the 21st century, there was a change in dominants of the community of small mammals, and the species richness increased. Of the five shrew species, only the common, tundra, and Eurasian pygmy shrews inhabit all biotopes. Their total proportion in each biotope varied between 16 to 38%. Among the 11 rodent species, the narrow-headed vole is the dominant species. Its total proportion in the community of small mammals was 38.3%. This species is characterized by a peculiar cycle of abundance. The reduction of steppe habitats has led to a decrease in the number of steppe lemming and a change in its population cycle. The proportion of other rodent species in the community of small mammals is low. [ABSTRACT FROM AUTHOR]

Despite its biogeographical uniqueness, where two vast savanna regions are separated by the Afromontane mosaic vegetation, there is a significant lack of small mammal sampling in the Tigray region of Ethiopia. Leveraging all our available data on rodents and shrews in the region, we tested the hypothesis that the Afromontane mosaic vegetation in the highlands acts as a barrier to gene flow between taxa found in the Somali-Masai and Sudanian savanna in the southeast and western lowland parts of the region, respectively. Morphological and DNA sequence analysis confirmed the presence of 23 species of small rodents and shrews in the region. We recorded 18 of these species in the Afromontane mosaic vegetation, seven species in the Sudanian savanna, and four species in the Somali-Masai savanna. Notably, the fauna of the Sudanian savanna was strikingly different from that of the Somali-Masai savanna at both intraspecific and interspecific levels, suggesting the northern Ethiopian highlands as a very strong biogeographic barrier for taxa adapted to arid lowlands. However, the reported species diversity remains provisional, and additional sampling from unexplored areas is needed. Furthermore, some of the reported taxa, in this study, such as Mus cf. tenellus, Crocidura cf. fuscomurina, Dendromus sp. indet. 2, and Otomys cf. cheesmani, require detailed taxonomic investigation and may represent new species. A robust understanding of the taxonomic diversity and distribution of the small mammals in the region is crucial for effective conservation planning as well as for addressing practical questions related to rodents, such as in public health and pest management. [ABSTRACT FROM AUTHOR]

Small mammals are potential bio-indicators of various ecosystems and their populations are often studied. However, many small mammal species are difficult to detect due to their small size and elusive behaviour. Camera trapping and live trapping are commonly employed survey techniques, but they both have their limitations. Recently developed techniques such as adjusted short-focal camera trapping and environmental DNA (eDNA) are promising new approaches, but their relative performance remains poorly quantified. We compared the effectiveness of three survey protocols for detecting a semi-aquatic and elusive small mammal, the Eurasian water shrew (Neomys fodiens), by (1) short-focal camera trapping, (2) live trapping, and (3) soil eDNA. During September and October 2022, we surveyed 20 transects of each 100 m in length alongside the Kleine Dommel, a lowland brook in the Netherlands. The effectiveness of the three survey protocols was compared based on detection probabilities. Short-focal camera trapping yielded a significantly higher detection probability than the eDNA protocol. Detection probabilities between short-focal camera trapping and live trapping and, between the eDNA protocol and live trapping, were not significantly different. Short-focal camera trapping is an effective technique to survey Eurasian water shrews. Furthermore, this method detected additional species compared to live trapping and is non-invasive and less labour-intensive. Short-focal camera trapping showed a promising method for small mammal surveys in general and we recommend further evaluation of its applicability for other small mammal species. [ABSTRACT FROM AUTHOR]

The materials of our studies on the taiga shrew (Sorex isodon Turov, 1924) in the northeastern part of European Russia are summarized. Its distribution is shown to coincide generally with the northern border of the taiga zone. The optimal biotopes are grass spruce forests (only for them are the values of the biotope fidelity coefficient positive). The numbers of taiga shrews in lowland localities are 0–2.4 individuals, while in foothill habitats it increases up to 4.4–8.6 individuals and reaches maximum values on the western slope of the northern Urals (28 individuals per 100 cone-nights). The formation of the numbers of the species is much influenced by the landscape conditions of the territory: the ratio of habitat types and their areas. An increase in the area of grass forests leads to an increase in the abundance of taiga shrews. [ABSTRACT FROM AUTHOR]

Abstract—In an intermontane kettle in the southwestern spurs of the Bureinskii Mountain Range, in the Bureya River basin, the Ussuri white-toothed shrew has been recorded for the first time. This locality lies north of the previously supposed species distribution range in the southern part of the Russian Far East. Study of the female karyotype has allowed us to describe the morphology of the chromosomes of Crocidura lasiura (2n = 40, NF = 54). The karyotype differs from the earlier published information (2n = 40, NF = 56) in the number of subtelocentric autosomes. The data obtained expand the northern range limit of the Ussuri white-toothed shrew and show variability in the number of chromosome arms (NFa = 50, 52). [ABSTRACT FROM AUTHOR]

The Seimchan–Buyunda Depression in the basin of the upper reaches of Kolyma River is distinguished by a number of natural and climatic features: the presence of an extensive ground-filtration talik, rich vegetation of the valley forest complex, and relatively high summer temperatures. The structure of shrew community in the Seimchan–Buyunda Depression also differs significantly from that of the adjacent territories. With an obvious dominance of Sorex caecutiens, S. isodon stably occupies a subdominant position there. Within the Okhotsk–Kolyma region, such a high proportion of S. isodon in the shrew community is more typical of northern Cisokhotia. Thus, the Seimchan–Buyunda Depression is a kind of "oasis" for the species that must have entered the Upper Kolyma River from the Sea of Okhotsk coast. [ABSTRACT FROM AUTHOR]

Myosorex varius is a South African generalist shrew, which has been found to consist of several genetic clades across its range. A northern clade inhabits the more mesic, summer-rainfall areas of grassland and savannah in the east of South Africa. A southern clade occupies areas of fynbos in the south, and can be further divided into a western subclade occupying winter-rainfall areas and an eastern subclade occupying areas with aseasonal rainfall. Non-South-African members of the African genus Myosorex primarily are limited to isolated montane habitats along the East African Rift System. Here, we used palaeoclimatic niche modelling to examine the effects of Pliocene and Pleistocene climate change on the distributions of M. varius, its clades and the genus as a whole. Results indicate that repeated cycles of range expansion during glacial periods and fragmentation during interglacials are responsible for current phylogeographic patterns within M. varius. Based on their close alignment with rainfall zones and lack of genetic mixing despite areas of contact, it is likely that these (sub)clades are locally adapted to their respective areas. Earlier climatic fluctuations allowed the genus to 'island hop' south from East Africa along the East African Rift System, expanding in range during cooler periods and retreating to montane refugia during warmer periods. Areas currently occupied by Myosorex species largely correspond with predicted montane refugia that have allowed them to survive previous warm periods. [ABSTRACT FROM AUTHOR]

Environmental conditions can influence the individual development of organisms and their morphological variability at the population level. The dimensions and proportions of the skull and lower jaw of immature shrews (Sorex araneus, S. caecutiens, and S. minutus), which were captured in August in regenerating clearings in the middle taiga of northeastern Europe, depended on the stage of abundance dynamics ("peaks" or "depressions"). For all three species from the same taxocenosis, a statistically significant reduction in the skull and jaw was observed against the background of the high abundance in captures and the multidimensional morphological niches corresponding to different abundance stages were significantly separated. The parameters of morphological diversity (entropy and self-organization index) depended on the amplitude of fluctuations in species occurrence; however, they varied within the limits characteristic of mammals. Along with Dehnel's phenomenon, natural population fluctuations may be one of the main factors determining the pattern of dynamics of the individual development and spatiotemporal variability of the morphological diversity of shrews. [ABSTRACT FROM AUTHOR]

The temporal variation of the degree of fluctuating asymmetry of the characters of skull morphology, as a measure of the developmental stability, is evaluated in the common shrew (Sorexaraneus L., 1758) in Central Siberia. Four-year cycles in this population under conditions of climatic stability in the past century were accompanied by significant changes in the level of developmental stability, suggesting a negative impact under a high density. Population fluctuations under the conditions of climatic instability in this century commonly occur without essential changes in the developmental stability, which can be related to both the impact of oscillations in the environmental conditions and an increase in the carrying capacity of the habitat due to the increase in temperature. Deterioration of developmental stability takes place occasionally in the case of an adverse overpopulation impact in the year of peak population abundance that is beyond the certain threshold level, which has increased due to climate change. The results indicate the importance of simultaneous monitoring of population abundance and developmental stability to provide information on possible mechanisms of changes in the population dynamics that occur due to climate change. [ABSTRACT FROM AUTHOR]

The population dynamics of shrews (Soricidae) are not well known even though they form an important part of forest ecosystems and represent suitable bioindicators of ecosystem quality. The aim of this study was to evaluate the population dynamics of shrews in mountain and upland forest clearings in four study areas within the Czech Republic and to reveal how climatic factors influenced fluctuations in their abundance for a decade (2007–2017). In total, we trapped 7,538 individuals of 18 small mammal species. From 760 individuals of seven shrew species, the common shrew (Sorex araneus) was significantly dominated in all study areas. We did not observe any significant, regular multi-annual cycles of the common shrew. However, a cross-correlation in density fluctuation of this species was detected in all mountain areas indicating the influence of environmental factors acting on a larger geographical scale. The autumn abundance of shrews was dependent on the subset of climatic variables, together explaining 56% of the variance in the linear regression model. Except for the length of the snow cover of ≥ 5 cm, all other significant variables were associated with North Atlantic Oscillation (NAO). Longer duration of snow cover during the winter before trapping, higher average NAO value during months before trapping, and NAO value in September influenced negatively the autumn abundance of shrews, contrary, higher value of NAO in May and October increased the abundance. Our results demonstrate the sensitivity of shrews to winters with a longer period of snow cover and to climatic oscillations associated with the NAO, whose effect is monthly dependent and probably indirectly influencing shrews through their prey. [ABSTRACT FROM AUTHOR]

The Eurasian shrew and vole tick Ixodes trianguliceps Birula lives in the nests and burrows of its small mammalian hosts and is—along with larvae and nymphs of Ixodes ricinus or Ixodes persulcatus—one of the most commonly collected tick species from these hosts in its Eurasian range. Ixodes trianguliceps is a proven vector of Babesia microti. In this study, up-to-date maps depicting the geographical distribution and the climate preference of I. trianguliceps are presented. A dataset was compiled, resulting in 1161 georeferenced locations in Eurasia. This data set covers the entire range of I. trianguliceps for the first time. The distribution area between 8 ∘ W–105 ∘ E and 40–69 ∘ N extends from Northern Spain to Western Siberia. To investigate the climate adaptation of I. trianguliceps, the georeferenced locations were superimposed on a high-resolution map of the Köppen–Geiger climate classification. The Köppen profile for I. trianguliceps, i.e., a frequency distribution of the tick occurrence under different climates, shows two peaks related to the following climates: warm temperate with precipitation all year round (Cfb), and boreal with warm or cold summers and precipitation all year round (Dfb, Dfc). Almost 97% of all known I. trianguliceps locations are related to these climates. Thus, I. trianguliceps prefers climates with warm or cold summers without dry periods. Cold winters do not limit the distribution of this nidicolous tick species, which has been recorded in the European Alps and the Caucasus Mountains up to altitudes of 2400 m. Conversely, I. trianguliceps does not occur in the Mediterranean area with its hot and dry summers. [ABSTRACT FROM AUTHOR]

Albinism is a hypopigmentation disorder which occurs as a consequence of mutations in genes involved in melanin biosynthesis. It is recorded in many mammalian species but is generally considered to be rare in natural populations. Here, we describe a fully albino individual of the common shrew Sorex araneus found in south-western Poland. We also present previous findings of albino specimens of this species in Europe. Since the 1960s, there have only been three confirmed records of wholly albino individuals of common shrews in mainland Europe; however, albinism has been recorded more frequently in this species from Britain. In other shrew species, wholly albino individuals are also recorded very rarely. [ABSTRACT FROM AUTHOR]

Understanding the processes that affect the dispersal distance is essential from perspective of ecology and evolution. It is essential to understand processes that affect dispersal distances. Dispersal distances can may depend on environmental and demographic factors and on the motivation of an individual. Effective dispersal results in the distribution of related genotypes in space. The distribution of pairwise distances between related common shrews (sibs and half-sibs) is characterized by a nonrandom increase in the number of relatives at distances up to 200 m. Aggregations of relatives are formed in a part of individuals dispersed in a random direction to the nearest available home rang ("stright-line search"). The distribution of all distances between relatives (up to 1200 m) is satisfactorily approximated by the straight-line search model and is not consistent with the "spiral search" model as it is; however, the best match can be achieved by combining these two search types. The latter model variant ("mixed search") assumes that the population includes animals with different personal traits: "superficial" and "thorough" explorers. Thorough explorers search for a vacant territory employing the spiral search strategy and correspond to "dreamers" in the model describing the movement and habitat selection strategy (MHSS). If vacant territories are in deficit and the environment is favorable, dreamers move over long distances and become randomly distributed in space: a random dispersion of related genotypes was recorded at distances from 200 to 1200 m. Therefore, searches for a dream territory in combination with a shortage of vacant territories (an accident) result in a random dispersal of related genotypes within a radius of at least 1200 m. The combination of temporal aggregations of relatives and the dispersal of related genotypes over a vast area explain well the previously discovered combination of an excess of homozygous alleles and a high allelic diversity. [ABSTRACT FROM AUTHOR]

Sustainable (no trend in the abundance of interacting species) coexistence of species can be maintained due to fluctuations in their abundance and distribution over habitats in a heterogeneous environment. The water shrew and common shrew, coexist in near-water areas and occasionally in "dry" habitats, where the water shrew periodically invades. Given the well-known overlapping of food niches of these species, one would expect the discovery of mechanisms that reduce competition; however, in "dry" habitats, we did not find such mechanisms. The use of space is characterized by a random overlapping of the home ranges of animals. In the preference test (a container with an animal versus an empty container), individual repeatability of sociability was found in tests with a conspecific stimulant, but was absent in tests with a stimulant of another species. The presence of the water shrew (as a stimulant) in the behavioral test did not increase the anxiety of common shrews, but only increased the thoroughness of exploration. No reaction of the water shrew to the common shrew was found in interspecific tests. In the absence of specific adaptations aimed at the spatial segregation of animals, the coexistence of the water shrew and the common shrew is quite well explained by "fluctuation-dependent" models of coexistence. [ABSTRACT FROM AUTHOR]

Crocidura, white-toothed shrews, is the most species rich genus among mammals. Phylogeny at the species-level is still unresolved, especially for Turkey and its adjacent regions. To understand phylogenetic relationships and mitogenomic features of Turkey's Crocidura, we aimed to (i) sequence whole mitogenomes of Turkish shrews, (ii) determine phylogenetic relationships among/within the Crocidura suaveolens group and C. leucodon from Turkey by using mitogenomes minus D-loop; (iii) contribute to resolving the phylogenetic position of populations within the C. suaveolens group in a phylogeographical context by using mitochondrial CYTB gene alone, and (iv) discuss the role of possible glacial refugia that may have driven the diversification of some taxa within Crocidura. Based on two data sets, all analyses revealed that the Turkish shrews were divided into three major lineages: C. mimula, C. gueldenstaedtii, and C. leucodon. This was in agreement with results of previous studies, suggesting (i) that the taxa within the C. suaveolens group such as C. caspica, C. cypria, C. gueldenstaedtii, C. iculisma, C. mimula, and C. shantungensis were separate species. However, the existence of C. sibirica could not be confirmed. We also proposed (i) Carpathian and Caucasian refugia for C. mimula and C. gueldenstaedtii, respectively, and (ii) the existence of a new refugium for C. leucodon that covers Uludağ-Bursa and its adjacent surroundings in the southern Marmara region. Moreover, the Turkish samples of C. leucodon were clustered into two sublineages, and mimula shrews from Lesvos-Greece and Western Anatolia-Turkey might represent an undetermined or undescribed taxon. [ABSTRACT FROM AUTHOR]

The article discusses the potential of using tree shrews as a preferred animal model for studying nephrolithiasis, a disease characterized by kidney stone formation. Tree shrews share similarities with primates in terms of tissue anatomy, physiology, biochemistry, and immune responses. Compared to rodents commonly used in research, tree shrews offer distinct advantages such as small size, short reproductive cycle, ease of experimental manipulation, and low feeding expenses. The study found that tree shrews were able to develop kidney stones more effectively than mice and rats, making them a promising surrogate animal for investigating kidney calculus. [Extracted from the article]

We investigated the prevalence of Bartonella in 123 northern bats (Eptesicus nilssonii) and their ectoparasites from Hokkaido, Japan. A total of 174 bat fleas (Ischnopsyllus needhami) and two bat bugs (Cimex japonicus) were collected from the bats. Bartonella bacteria were isolated from 32 (26.0%) of 123 bats. Though Bartonella DNA was detected in 79 (45.4%) of the bat fleas, the bacterium was isolated from only one bat flea (0.6%). The gltA sequences of the isolates were categorized into genotypes I, II, and III, which were found in both bats and their fleas. The gltA sequences of genotypes I and II showed 97.6% similarity with Bartonella strains from a Finnish E. nilssonii and a bat flea from a E. serotinus in the Netherlands. The rpoB sequences of the genotypes showed 98.9% similarity with Bartonella strain 44722 from E. serotinus in Republic of Georgia. The gltA and rpoB sequences of genotype III showed 95.9% and 96.7% similarity with Bartonella strains detected in shrews in Kenya and France, respectively. Phylogenetic analysis revealed that Bartonella isolates of genotypes I and II clustered with Bartonella strains from Eptesicus bats in Republic of Georgia and Finland, Myotis bats in Romania and the UK, and a bat flea from an Eptesicus bat in Finland. In contrast, genotype III formed a clade with B. florencae, B. acomydis, and B. birtlesii. These data suggest that northern bats in Japan harbor two Bartonella species and the bat flea serves as a potential vector of Bartonella transmission among the bats. [ABSTRACT FROM AUTHOR]

Whether environmental DNA (eDNA) testing methods are effective for semi-aquatic organisms that spend time both in rivers and on land remains unclear. We designed a species-specific primer–probe set for the semi-aquatic Japanese water shrew, Chimarrogale platycephala, an endangered top predator species for which limited ecological information is available. The designed primer–probe set was used to determine the effective sampling time for detecting eDNA from this species in running water. Hourly water sampling was conducted for 25 h in the autumn of 2020. Water sampling and camera trapping were conducted in the two streams in which feces had been observed on stream rocks. No C. platycephala activity was captured by the camera traps at any sampling point during the investigation. However, eDNA was mainly detected at night in both streams and twice during the daytime in one stream; the eDNA detection periods differed between streams (21:00–23:00 vs. 1:00–8:00 and daytime). These results demonstrate that eDNA testing methods are effective for detecting small semi-aquatic mammals. However, the sampling time affected the results, and eDNA was mostly detected at night, possibly because of the nocturnal activity of the species. Therefore, the sampling time should be adjusted to match the activity period of a species to improve the efficiency of eDNA testing for semi-aquatic organisms. [ABSTRACT FROM AUTHOR]

The first data on the cestode fauna of shrews in the North Caucasus, in particular, its western and central parts, are presented. In total 27 cestode species from 17 genera and two families (Hymenolepididae and Dilepididae) have been revealed. Most of the fauna is composed of taxa with transpalaearctic distributions, these amounting to 55.6% of the species diversity. European and Caucasian (endemic) elements account for 18.5 and 25.9% of all species, respectively. The cestodes Pseudobothriolepis mathevossianae and Coronocanthus sp. are recorded from the Caucasus for the first time. The genera Coronocanthus, Monocercus, Neoskrjabinolepis, Spasskylepis, and Soricinia contain species morphologically different from the known congeners, all probably new and thus likely to increase the number of species endemic to the region. The tapeworms species diversity of the mesophilous host species (Sorex and Neomys) is higher compared to xerophilous ones (Crocidura), amounting to 23 and four species, respectively. The infestation rate of the North Caucasian shrews by different cestode species is analyzed. [ABSTRACT FROM AUTHOR]

A quantitative assessment of nonresidency (movements outside the home range) in the common shrew was carried out. A feature of shrews, i.e., the predominant falling of nonresident animals into traps of the "trap" type (pitfall), was used. Based on a comparison of the abundance of animals in the same area over five years, comparative data were obtained on the daily value of the flow of nonresidents detected on the line of live-traps and in fences with dug buckets. The synchronism of the long-term dynamics of the abundance of nonresidents accounted for in different ways is found. Based on the number of animals caught per linear meter of fences, the daily density of nonresidents was calculated. It was found that in some years the daily density of nonresidents can exceed the density of the settled population many times over. The coefficient that the author proposes to use in the marking technique makes it possible to bring the number of nonresidents detected on the line of live-traps with the number of nonresidents detected in fences. [ABSTRACT FROM AUTHOR]

The main features of the ecology and behavior of the slender-tailed tree shrew based on observations in southern Vietnam at Cat Tien National Park (11°25′ N, 107°25′ E) are described. Slender-tailed tree shrews inhabit parts of forests where bamboo or rattan grows, abandoned gardens, and fields overgrown with tall grasses and bamboo. They consume insects and spiders found on the ground surface and in leaf piles and seek invertebrates inside rotten trunks. Tree shrews trace birds and catch disturbed prey; sometimes, they try to steal food caught by birds. Usually, these shrews build individual nests with dry leaves for night rest in open places without any shelters. During the period of observations (November–June), tree shrews were found in pairs on small (~0.5 ha) territories. The animals in pairs maintained visual or acoustic contacts with each other. They designated territories by cries and odor marks that were left on bamboo stems or rattan lianas. Several territorial conflicts were observed. Copulation took place in February–March, and the young appeared in March–April. In spite of the active use of the ground surface, the slender-tailed tree shrew has locomotion typical for an arboreal animal, in contrast to the majority of representatives of the Tupaiidae family. [ABSTRACT FROM AUTHOR]

Of the eleven species of shrews described in Iran, the Etruscan shrew (Suncus etruscus), the smallest known extant mammal by mass, is recorded in northern and southern provinces. During rodent control programs, a female S. etruscus was trapped and found naturally infected with a trematode which was morphologically identified as Brachylaima sp. This finding represents the first report of trematodiasis in this host species. [ABSTRACT FROM AUTHOR]

Genetically engineered chymosin from the tree shrew (Tupaia belangeri chinensis) has been obtained and partially characterized for the first time. The target enzyme was produced in Escherichia coli, strain BL21(DE3). It was shown that tree shrew recombinant chymosin coagulates cow milk (Bos taurus). The total and specific milk-clotting activity of the obtained enzyme was 0.7–5.3 IMCU/mL and 8.8–16.6 IMCU/mg. The nonspecific proteolytic activity of tree shrew recombinant chymosin in relation to total bovine casein was 30 and 117% higher than that of recombinant chymosin of cow and of single-humped camel respectively. It was found that in comparison with most of the known genetically engineered chymosins, the tree shrew enzyme showed exceptionally low thermal stability. After heating at 45°C, the coagulation ability of tree shrew recombinant chymosin decreased by more than 40%, and at 50°C the enzyme lost more than 90% of the initial milk-clotting activity. The Michaelis constant (Km), enzyme turnover number (kcat), and catalytic efficiency (kcat/Km) for genetically engineered chymosin from the tree shrew were 6.3 ± 0.1 µM, 11 927 ± 3169 s–1 and 1968 ± 620 µM–1 s–1, respectively. Comparative analysis showed that the primary structure of the chymosin-sensitive site of cow kappa-casein and the supposed similar sequence of tree shrew kappa-casein differed by 75%. The ability of tree shrew recombinant chymosin to coagulate cow's milk, along with a low thermal stability and high catalytic efficiency with respect to the substrate, imitating the chymosin-sensitive site of cow kappa-casein, suggests that this enzyme is of potential interest for cheese making. [ABSTRACT FROM AUTHOR]

The long-term changes in the contents of heavy metals (Cu, Zn, Cd, Рb) in the food and liver of four shrew species of the g. Sorex, in the vicinity of the the Middle Ural Copper Smelter (MUCS) during periods of its high (1990–1997), reduced (1998–2009), and almost ceased (2010–2019) emissions. The minimum concentrations of all elements in the animal organism were noted in unpolluted areas (background zone), the maximum concentrations of Cu, Zn, and Cd were in the immediate vicinity of the plant (impact zone), Cd—at moderate pollution (buffer zone). The species specificity of the accumulation of the considered elements in the liver was determined by the composition of diets and was expressed in increased accumulation of Cu and Cd in the liver of S. araneus and increased accumulation of Pb in the liver of S. caecutiens. A multiple reduction in industrial emissions did not lead to an equivalent decrease in the content of heavy metals (HMs) either in the feed or in the body of shrews. Over 30 years, directed changes in HM concentrations in the liver were noted only in S. caecutiens: in the impact zone (1–3 km from the plant), the content of Zn did not change, the concentrations of Cd and Pb decreased by 1.2–1.5 times, while the concentration of Cu, on the contrary, increased by 1.5 times. In the buffer zone (4–10 km) Cu, Zn, and Pb concentrations remain unchanged, while the concentrations of Cd decreased by 1.5 times; in the background area (20–34 km), the content of essential elements (Cu, Zn) was maintained at the same level, while the concentration of toxic elements (Cd and Pb) decreased by 4–5 times. [ABSTRACT FROM AUTHOR]

The rodents and shrews are important reservoirs for a large number of zoonotic pathogens. Here by performing a literature review, we determined the occurrence and distribution of rodents and shrews in China at three scales including province, city, and county levels. The peer-reviewed papers published in English and Chinese were collected, standard procedures were applied in reference books, field surveys and websites to remove duplicates, and information on recorded locations of rodents and shrews was extracted. The dataset contains 13,911 records of geo-referenced occurrences for 364 rodents and shrews distributed over 1,663 locations distinguished. As pathogens continue to emerge from rodents and shrews, this dataset could assist efforts to put preliminary bounds around a variety of spatial analyses of rodents and shrews, facilitate a better understanding of the transmission risk of the pathogens they carry, and be helpful for assessing the risk of future emergence of rodent-borne zoonoses. Measurement(s) diversity and distribution of rodents and shrews Technology Type(s) literature review Factor Type(s) diversity and distribution Sample Characteristic - Organism rodents • shrews Sample Characteristic - Environment diversity • distribution Sample Characteristic - Location China [ABSTRACT FROM AUTHOR]

Most neurons in the primary visual cortex (V1) of mammals show sharp orientation selectivity and band-pass spatial frequency tuning. Here, we examine whether sharpening of the broad tuning that exists subcortically, namely in the retina and the lateral geniculate nucleus (LGN), underlie the sharper tuning seen for both the above features in tree shrew V1. Since the transition from poor feature selectivity to sharp tuning occurs entirely within V1 in tree shrews, we examined the orientation selectivity and spatial frequency tuning of neurons within individual electrode penetrations. We found that most layer 4 and layer 2/3 neurons in the same cortical column preferred the same stimulus orientation. However, a subset of layer 3c neurons close to the layer 4 border preferred near orthogonal orientations, suggesting that layer 2/3 neurons may inherit the orientation preferences of their layer 4 input neurons and also receive cross-orientation inhibition from layer 3c neurons. We also found that layer 4 neurons showed sharper orientation selectivity at higher spatial frequencies, suggesting that attenuation of low spatial frequency responses by spatially broad inhibition acting on layer 4 inputs to layer 2/3 neurons can enhance both orientation and spatial frequency selectivities. However, in a proportion of layer 2/3 neurons, the sharper tuning of layer 2/3 neurons appeared to arise also or even mainly from inhibition specific to high spatial frequencies acting on the layer 4 inputs to layer 2/3. Overall, our results are consistent with the suggestion that in tree shrews, sharp feature selectivity in layer 2/3 can be established by intracortical mechanisms that sharpen biases observed in layer 4, which are in turn inherited presumably from thalamic afferents. [ABSTRACT FROM AUTHOR]

Malagasy shrew tenrecs (Microgale) have increasingly been used to study speciation genetics over the last years. A previous study recently uncovered gene flow between the Shrew-toothed shrew tenrec (M. soricoides) and sympatric southern population of the Pale shrew tenrec (M. fotsifotsy). This gene flow has been suggested to be accompanied by complete mitochondrial replacement in M. fotsifotsy. To explore the temporal framework of this replacement, we assembled mitogenomes from publicly available sequencing data of ultra-conserved elements. We were able to assemble complete and partial mitogenomes for 19 specimens from five species of shrew tenrecs, which represents a multifold increase in mitogenomic resources available for all tenrecs. Phylogenetic inferences and sequence simulations support the close relationship between the mitochondrial lineages of M. soricoides and the southern population of M. fotsifotsy. Based on the nuclear divergence of northern and southern populations of M. fotsifotsy and the mitochondrial divergence between the latter and M. soricoides, there was a mean time window for replacement of ~ 350,000 years. This timeframe implies that the effective size of the ancestral M. fotsifotsy southern population was less 70,000. [ABSTRACT FROM AUTHOR]

The dependence among the content of energy reserves in Sorex caecutiens, the abundance of food objects, and the number of shrews in the summer periods of 2012–2019 was estimated. The glycogen content in the liver of S. caecutiens did not show a significant relationship to the number of animals. The mass of fat depots and the relative biomass of invertebrates (according to the counting data obtained with the pitfall traps) in August were inversely related to the total number of all species of shrews inhabiting the territory. The mass of the adipose tissue of S. caecutiens positively correlated with the biomass of insect larvae (primarily of caterpillar-like ones, which constituted the bulk of larvae in the samples). The revealed features indicate an increase in intra- and interspecific food competition during the years of high numbers of shrews. [ABSTRACT FROM AUTHOR]

In a 7-year capture-recapture analysis, we estimated effects of population density and weather conditions on the mortality rate in five neighbouring populations located in different habitats in Central Russia. Non-resident shrews had little chance of surviving to reproduction. The average lifespan of resident young shrews first seen in June, July and August was 4.7, 4.5 and 3.2 months, respectively, and the longest one was 15 months. In spring, the number of males that overwintered exceeded that of females; subsequently, the former diminished faster leading to a female-biased sex ratio in late summer. Young common shrews survived the winter usually close to their summer home ranges, although several > 100 m shifts were recorded. The number of newly discovered overwintering shrews positively correlated (r = 0.93, P < 0.008) with the expansion of home ranges after wintering. The pattern of the resident population had formed by the end of July; later, only a few new residents were detected, although the dispersal rate remained high. The major contribution of the shrews that overwintered locally to the genetic pattern explains the previously observed deficit of heterozygotes at three of the studied sites. Although the interannual dynamics of mortality varied among the habitats, overall mortality was high in the 2 years with the thinnest late-autumn snow cover. An association of the mortality rate with population abundance was found only in the most favourable habitat. The occasional high mortality and asynchronous survival give immigrants an opportunity from time to time enhance the genetic diversity of local populations. [ABSTRACT FROM AUTHOR]

Rationale: The fatty acid amide oleoyl glycine (OlGly) and its more stable methylated form oleoyl alanine (OlAla) reduce naloxone-precipitated morphine withdrawal (MWD)-induced conditioned gaping (nausea) responses in rats. In addition, OlGly has been shown to reduce lithium chloride (LiCl)–induced conditioned gaping in rats and vomiting in Suncus murinus (house musk shrews). Objectives: Here, we compared the potential of these fatty acid amides to maintain their anti-nausea/anti-emetic effect over a delay. The following experiments examined the potential of a wider dose range of OlGly and OlAla to interfere with (1) LiCl-induced conditioned gaping in rats and (2) LiCl-induced vomiting in shrews, when administered 20 or 70 min prior to illness. Results: OlAla (1, 5, 20 mg/kg) reduced LiCl-induced conditioned gaping, with OlGly only effective at the high dose (20 mg/kg), with no effect of pretreatment delay time. At the high dose of 20 mg/kg, OlGly increased passive drips during conditioning suggesting a sedative effect. In shrews, both OlGly and OlAla (1, 5 mg/kg) suppressed LiCl-induced vomiting, with no effect of pretreatment delay. OlAla more effectively suppressed vomiting, with OlAla (5 mg/kg) also increasing the latency to the first vomiting reaction. Conclusions: OlAla was more effective than OlGly in reducing both LiCl-induced gaping in rats and LiCl-induced vomiting in shrews. These findings provide further evidence that these fatty acid amides may be useful treatments for nausea and vomiting, with OlAla demonstrating superior efficacy. [ABSTRACT FROM AUTHOR]

We studied the polymorphism of the cytb gene in two forms of the Lesser White-toothed Shrew species complex: Crocidura suaveolens s. stricto and C. sibirica. The haplotypes of C. sibirica are found to be very similar to those of Crocidura suaveolens. They do not belong to a distinct haplogroup. The molecular diversity of the populations in the Asian part of the range is higher than in Eastern Europe. For the combined sample from Asia and Europe together, we revealed a significant signal of population expansion. Analysis of the expansion time showed that the Asian territory was colonized earlier (before the last glacial maximum) than the Eastern Europe (at the very end of the Late Pleistocene and in the early Holocene). The results of the ancestral area reconstruction are consistent with the hypothesis of a Middle Asian origin of the C. suaveolens/C. sibirica group, recent colonization of Inner Asia and later penetration into Eastern Europe. [ABSTRACT FROM AUTHOR]

The Accra Plain of Ghana is experiencing rapid urbanization, but there is scant information on its impact on local biodiversity. We assessed the changes in land use/land cover of the Accra Plain since 1991 and evaluated how the observed changes have influenced local small mammals in forest fragments. We applied supervised classification and intensity analysis time-series Landsat imagery data to assess land use/land cover changes between 1991 and 2017. Small mammals were surveyed in two forest fragments, the Pinkwae and Adumanya forests from June 2019 to January 2020, using capture-mark-recapture technique. We compared our data with baseline data gathered in 1991–1992, when large areas of the city remained mostly undeveloped. Our data revealed that the urban area has increased by 832%, while the forest area declined by 85% between 1991 and 2017. The Pinkwae and Adumanya forests, which covered 120 and 1.5 ha, respectively, in 1991 have each been reduced to < 1 ha. We found changes in the small mammal species composition in the forest fragments, but not species richness due to species turnover. Grammomys poensis and Dephomys defua are first records for the Accra Plain. Our data suggested that small forest fragments within the urbanizing landscape are important for maintaining the local small mammal species. For the conservation of local small mammals in urbanizing landscapes, it is important to maintain the greatest possible number of small forest fragments and establish policies that prevent forest remnants from being further depleted. [ABSTRACT FROM AUTHOR]

The first finds of the fossil remains of the members of the genus Chodsigoa outside China are described from the Pleistocene of northern Vietnam. They are assigned to C. caovansunga Lunde, Musser et Son, 2003 (a maxillary fragment with A3–M3, an isolated M1, and a dentary with I1 and P4–M2) from the Middle Pleistocene of the Tham Hai cave (Lang Son Province) and C. hoffmanni Chen et al., 2017 (a maxillary fragment with P4–M2) from the Upper Pleistocene of the Lang Trang cave (Thanh Hoa Province). The described specimens are the first fossil finds of these species. They indicate that representatives of the genus Chodsigoa in Vietnam spread to the south much further in the Pleistocene than today. [ABSTRACT FROM AUTHOR]

We studied the distribution of chigger mite species over mammal hosts, attachment sites on the host body, habitats, and seasons in Iran. The study was based on 2155 specimens of 36 chigger species collected from 10 species of Muridae, Cricetidae, and Soricidae across six provinces of northern Iran. A high level of mixed infestation by chiggers was recorded—76% of hosts parasitized by chiggers were infested by more than one (2–8) species. Statistically significant differences in the preference for anterior and posterior parts of the host body were found. Three species—Neotrombicula lubrica, N. delijani, and Cheladonta firdousii—preferred the posterior part of the host body; 12 species were characterized by the occurrence in the anterior part and differed from one another by the frequency of presence in the posterior part. One species, Hirsutiella alpina, was found only in the anterior part of the host body (inside the ears of rodents). The most diverse chigger fauna was on the fringe of Golestan National Park (species richness = 21, Shannon–Wiener index = 2.823). The chigger fauna of the high-mountain localities on the Alborz Range was the least diverse (species richness = 16, Shannon–Wiener index = 2.439). The seasonal aspect of activity was evident for Neotrombicula elegans, which exposed the autumn–winter period of the occurrence on hosts, and N. vernalis, with the winter-spring peak of abundance. [ABSTRACT FROM AUTHOR]

Among seven species of the order Eulipotyphla (from southern Gansu and northern Sichuan Provinces, Central China) studied cytogenetically, karyotypes of one talpid species, Uropsilus aff. soricipes (2n = 36, NFa = 54), and three soricid species, Chodsigoa hypsibia (2n = 65, NFa = 66), Sorex cansulus (2n = 42, NFa = 64) and Sorex thibetanus (2n = 42, NFa = 60), are described cytogenetically for the first time. All four species are endemic to China with distribution ranges restricted to the Qinghai–Tibet Plateau and adjacent mountain ranges. The Ch. hypsibia karyotype consists of mostly acrocentric autosomes and one metacentric pair of autosomes; besides, a B chromosome was identified. No polymorphism was detected among karyotypes of other species, including shrews Sorex bedfordiae (2n = 26, NFa = 44), Anourosorex squamipes (2n = 48, NFa = 92) and Crocidura suaveolens (2n = 40, NFa = 44). The Chinese shrew mole U. aff. soricipes and three shrew species (S. bedfordiae, Ch. hypsibia and A. squamipes) represent autochthonous fauna of Central/Western China, whereas S. thibetanus, S. cansulus and C. suaveolens belong to phylogenetic groups occurring mostly to the north and west from China; therefore, they should be considered relatively recent colonisers. Thus, considering the relationships of the species within phylogenetic groups, our results on karyotypes are in good agreement with molecular genetic data. [ABSTRACT FROM AUTHOR]

Powassan virus lineage 2 (deer tick virus) is an emergent threat to American public health, causing severe neurologic disease. Its life cycle in nature remains poorly understood. We use a host-specific retrotransposon-targeted real time PCR assay to test the hypothesis that white-footed mice, considered the main eastern U.S. reservoir of the coinfecting agent of Lyme disease, is the reservoir for deer tick virus. Of 20 virus-infected host-seeking nymphal black-legged ticks 65% fed on shrews and none on mice. The proportion of ticks feeding on shrews at a site is positively associated with prevalence of viral infection, but not the Lyme disease agent. Viral RNA is detected in the brain of one shrew. We conclude that shrews are a likely reservoir host for deer tick virus and that host bloodmeal analysis can provide direct evidence to incriminate reservoir hosts, thereby promoting our understanding of the ecology of tick-borne infections. Goethert and colleagues use a host-specific retrotransposon targeted real time PCR assay on questing nymphal ticks to identify a reservoir for Powassan virus lineage 2 (or deer tick virus). Infected ticks were found to have preferentially fed on shrews, as opposed to white-footed mice as was expected, suggesting that they may be a reservoir host for this virus. [ABSTRACT FROM AUTHOR]

The long-term dynamics of β-diversity of small mammal (SM) communities in the vicinity of a large copper smelter has been analyzed during the periods of high (1990–1997), reduced (1998–2009), and almost terminated emissions (2010–2020). The results show that the β-diversity of communities increases as the smelter is approached, with the level of pollution playing a key role in the formation of community structure (up to 25%). Throughout the 30-year observation period, the background communities have been less variable than the buffer and impact communities; i.e., the more unstable the environment, the higher the community variability. Structural rearrangements in the impact and buffer communities in the period of emission reduction have resulted in the progressive divergence between the communities of background and polluted areas. [ABSTRACT FROM AUTHOR]

The remains of the white-toothed shrew Crocidura kornfeldi Kormos, 1934 (one skull fragment with almost complete dentition, the fragmental rostral part of a skull with the left upper incisor, a maxillary fragment, five mandibular fragments and an isolated upper incisor) from the Lower Pleistocene deposits of the Taurida cave in the central Crimea (Belogorsk district, Zuya village) are described. This earliest European species of the genus Crocidura was quite common in the Early Pleistocene of Central Europe and the Mediterranean; for the first time, it is described from Crimea and the entire Eastern Europe. [ABSTRACT FROM AUTHOR]

Rodent predators are implicated in declines of seabird populations, and removing introduced rats, often, but not always, results in the expected conservation gains. Here we investigated the relationship between small mammal (Norway rat, wood mouse and pygmy shrew) abundance and Manx shearwater breeding success on the island of Rum, Scotland, and tested whether localised rodenticide treatments (to control introduced Norway rats) increased Manx shearwater breeding success. We found that Manx shearwater breeding success was negatively correlated with late summer indices of abundance for rats and mice, but not shrews. On its own, rat activity was a poor predictor of Manx shearwater breeding success. Rat activity increased during the shearwater breeding season in untreated areas but was supressed in areas treated with rodenticides. Levels of mouse (and shrew) activity increased in areas treated with rodenticides (likely in response to lower levels of rat activity) and Manx shearwater breeding success was unchanged in treated areas (p < 0.1). The results suggest that, unexpectedly, negative effects from wood mice can substitute those of Norway rats and that both species contributed to negative impacts on Manx shearwaters. Impacts were intermittent however, and further research is needed to characterise rodent population trends and assess the long-term risks to this seabird colony. The results have implications for conservation practitioners planning rat control programmes on islands where multiple rodent species are present. [ABSTRACT FROM AUTHOR]

Social thermoregulation is the huddling of two or more individuals that share endogenous warmth to reduce thermoregulation costs. Strategies vary widely depending on the species' social behavior and the ambient ecological conditions. In greater white-toothed shrews (Crocidura russula), huddling is employed in communal nests only in the colder months, which suggests that temperature is an important factor in the species' social thermoregulation strategy. To test this hypothesis, we analyzed the behavior and physiology of five groups of shrews from winter, acclimated to 14 °C, and four groups from summer, acclimated to 24 °C. Each group consisted of six captive males that were first housed singly for 2 days and later allowed to interact with other shrews of the same group. Our analysis revealed all group mates were frequently found huddling in the same shelter, regardless of acclimation temperature. However, mass-adjusted resting metabolic rate decreased in winter shrews with larger huddle sizes and remained constant in summer shrews in huddles with three or more individuals. Body temperature was also significantly lower and more varied in winter shrews. After being group-housed, winter shrews used less torpor and significantly increased their body mass and food intake in the first days. Our results suggest that temperature had a small influence in huddling behavior but a large one in physiological factors, such as metabolism, body temperature, and food intake, after shrews started interacting socially. Therefore, social thermoregulation provides benefits to C. russula besides energy savings. Significance statement: Small mammals often huddle to reduce thermoregulation costs during cold. Previous studies in wild greater white-toothed shrews suggested that this species only employs social thermoregulation in the colder months of the year. We captured wild shrews and assessed the energetic advantages of this social thermoregulation strategy under controlled conditions. We confirmed that social thermoregulation indeed has more energetic benefits to shrews in winter than in summer. However, huddling between individuals still occurs at warm temperatures, when energetic benefits are no longer significant. Such observations suggest that huddling is advantageous to shrews in multiple ways beyond thermoregulation. Furthermore, social interaction between individuals influenced daily torpor, body mass, and feeding, further supporting the hypothesis that sociality in greater white-toothed shrews has direct and indirect effects on their energy budget. [ABSTRACT FROM AUTHOR]

The development of urban areas imposes challenges that wildlife must adapt to in order to persist in these new habitats. One of the greatest changes brought by urbanization has been an increase in anthropogenic noise, with negative consequences for the natural behavior of animals. Small mammals are particularly vulnerable to urbanization and noise, despite some species having successfully occupied urban environments. To understand some of the traits that have enabled small mammals to deal with the consequences of urbanization, we compared the behavioral responses of urban and rural greater white-toothed shrews, Crocidura russula, to different sound stimuli. A total of 32 shrews, 16 from each habitat, were exposed in captivity to four sound treatments: silence, tawny owl calls, traffic noise, and white noise. Urban and rural shrews showed different behaviors, with urban animals being more active, feeding more frequently, and using less torpor than rural individuals. However, responses to sound treatments were similar in both populations: urban and rural shrews exhibited a slight decrease in activity and feeding behavior, as well as more fleeing responses, when exposed to traffic noise or white noise, but not to owl calls. These results suggest urbanization induces long-term changes in the general activity of C. russula, but the short-term behavioral response to sound disturbance remains similar in rural and urban populations. [ABSTRACT FROM AUTHOR]

Purpose: The African continent has 452 chiggers (Trombidiformes: Trombiculidae) in 61 genera. One of these, Elianella Vercammen-Grandjean, 1956, has only two species known for Africa. The objective of the present study is to describe a new species for Equatorial Guinea, with the aim of increasing knowledge so scarce for Africa. Methods: In this study, we provide drawings, measurements and microscopy images on a Microscope Zeiss for the new species described below. Also, this type of the new species is deposited in the USNM. Results: We describe a new species of Elianella collected parasitizing the Bioko Forest Shrew, Sylvisorex isabellae Heim de Balsac (Eulipotyphla: Soricidae) from the insular Equatorial Guinea. Also, we are providing a key for the three species of Elianella. Conclusion: Finally, we are contributing to the knowledge of African species, due the fact this new species is the first chigger recorded to the Equatorial Guinea, on the west coast of Central Africa. [ABSTRACT FROM AUTHOR]

The rickettsial pathogen Orientia tsutsugamushi, causing scrub typhus, has been implicated as a major cause of acute encephalitis syndrome (AES) in many places in India including Gorakhpur district of Uttar Pradesh. Seasonal abundance of the principal vector mite of the pathogen, Leptotrombidium deliense, its animal hosts, and prevalence of infection on them are important attributes in the assessment of outbreaks of the disease. Hence, these aspects were investigated, seasonally, in rural villages of Gorakhpur district, where peak incidence of AES cases were reported. A total of 903 animals (rodents/shrews) was collected using 6484 Sherman traps in eight study villages (14% overall trap rate). A sum of 5526 trombiculid mites comprising 12 species was collected from 676 live rodents/shrews screened. Suncus murinus, the Asian house shrew was the predominant species (67%). Among trombiculids, the principal vector mite, L. deliense, was predominant (64.7%) and its infestation index (i.e., average number of chiggers per host animal) was 5.3. The L. deliense infestation index was higher during July to November with a peak in October. Out of 401 animal sera samples screened, 68% were positive for antibodies against O. tsutsugamushi. Of 465 blood samples tested by nested PCR, seven were positive for the 56 kDa gene of O. tsutsugamushi. In conventional PCR, 41 out of 265 samples were positive for the 60 kDa groEL gene of O. tsutsugamushi. Among the 5526 mite samples, tested as 352 pools through nested PCR, four pools were positive for 56 kDa gene. Phylogenetic analysis of 56 and 60 kDa genes confirmed circulation of Karp and TA678 (rodents) and TA678 (mite) serotypes of O. tsutsugamushi in Gorakhpur. Peak incidence of AES in Gorakhpur district occurs during the rainy season (July–October), coinciding with the peak abundance of L. deliense. These results indicate involvement of L. deliense as the vector mite transmitting the scrub typhus pathogen O. tsutsugamushi to humans in the rural areas of Gorakhpur district, India. [ABSTRACT FROM AUTHOR]