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1.
PLoS One ; 19(4): e0301841, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626103

RESUMO

The number of people suffering from scrub typhus, which is not of concern, is increasing year by year, especially in Yunnan Province, China. From June 1, 2021 to August 15, 2022, a total of 505 mammalian samples were collected from farm, forest, and residential habitats with high incidence of scrub typhus in Yunnan, China, for nPCR (nested PCR) and qPCR (quantitative real-time PCR) detection of Orientia tsutsugamushi. A total of 4 orders of murine-like animals, Rodentia (87.52%, n = 442), Insectivora (10.29%, n = 52), Lagomorpha (1.79%, n = 9) and Scandentia (0.40%, n = 2) were trapped. Comparing the qPCR infection rates in the three habitats, it was no significant difference that the infection rate of residential habitat (44.44%) and that of the farm habitat (45.05%, P>0.05), which is much larger than that of the forest habitat (3.08%) (P<0.001). Three genotypes (Karp-like, Kato-like and TA763-like) of O. tsutsugamushi were found from Yunnan, China in this study.


Assuntos
Orientia tsutsugamushi , Tifo por Ácaros , Humanos , Animais , Camundongos , Tifo por Ácaros/diagnóstico , Fazendas , China/epidemiologia , Orientia tsutsugamushi/genética , Roedores/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Epidemiológicos , Florestas , Eulipotyphla/genética
2.
PeerJ ; 11: e16098, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37842049

RESUMO

The gradient from natural to urban areas strongly associates with the structure of avian communities over that gradient. Most research on urban birds is from temperate areas and knowledge from tropical Southeast Asia is lacking. We examined bird species diversity, relative abundance, and species composition along an urban to rural gradient in three Myanmar cities, and assessed potential environmental factors responsible for the changes. We counted birds within 40 point-count sites with 50-m fixed-radius in three large cities of Myanmar, namely Mandalay, Mawlamyine, and Myeik. We distinguished four urban habitat types (Downtown-urban, University Campus-suburban, Paddy Field-agriculture, Hill-forest). We classified all species into migrant or resident and into major feeding groups and related with several environmental parameters such as 'impervious surface'. We counted 5,423 individuals of 103 species with roughly equal species diversity between the three cities. Rock Pigeon (Columba livia) was the most frequent species. The species composition differed significantly between the four major habitat types. Omnivores were more abundant in the city center than all other functional groups. Interestingly, insectivores were also predominant in the city center. In addition, more generalist' species occurred towards the city center compared to the periphery, indicating that the periphery has increased relevance for specialized birds. We found some marked differences in species composition between the three cities of Mandalay, Mawlamyine, and Myeik. Additionally to species composition, species diversity and relative abundance differed significantly between each of the four major habitat types in all three cities.


Assuntos
Biodiversidade , Urbanização , Humanos , Animais , Cidades , Columbidae , Ecossistema , Eulipotyphla
3.
PeerJ ; 11: e15888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37719121

RESUMO

Background: Several insectivorous bat species are found in New England, yet research on them is still scarce. Current research shows the ecological importance of bats due to their control of insect populations, but they are endangered by habitat loss and White Nose Syndrome, among other threats. Pine barrens are an uncommon ecosystem found in New England that supports other rare taxa and could be important for these bat species. Methods: With hand-held audio recorders, we surveyed for bats in Montague Plains Wildlife Management Area in Massachusetts and Concord Pine Barrens in New Hampshire in June 2022. Our study objectives were to (1) describe the most common bat species and (2) compare bat activity across different habitat types at two managed pine barrens in New England. In particular, we examined bat activity related to habitat type (scrub oak, mature pitch pine, treated pitch pine, hardwood forest), habitat structure (i.e., canopy closure), time since prescribed fire, and path width. We analyzed our data through generalized linear modeling and logistic regression. Results: Overall, we were able to measure the presence of five out of the nine total species found in the area, including the endangered Myotis lucifugus (little brown bat). We recorded 293 bat calls, with the majority of calls from big brown bats (71%). We found significant differences (p < 0.05) in bat activity in relation to time since prescribed fire and habitat structure. The index of bat activity was greatest in pitch pine and hardwood forests and lowest in scrub oak and treated pitch pine habitats. With preliminary data, we also found that silver-haired bat presence was influenced by habitat type, with more detections at survey points in hardwood forests. Discussion: These findings demonstrate the importance of pine barrens as an ecosystem that supports bats in New England. According to the activity of bats in our study, closed canopy and mature pitch pine habitats may be prioritized in conservation efforts at managed barrens for bat species. Further research is recommended to better understand the relationship between prescribed fires, which are common in managed barrens, and bat activity.


Assuntos
Quirópteros , Essências Florais , Pinus , Animais , Ecossistema , New England , Florestas , Massachusetts , Eulipotyphla
4.
PeerJ ; 11: e15943, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692121

RESUMO

Arthropods play a crucial role in terrestrial ecosystems, for instance in mediating energy fluxes and in forming the food base for many organisms. To better understand their functional role in such ecosystem processes, monitoring of trends in arthropod biomass is essential. Obtaining direct measurements of the body mass of individual specimens is laborious. Therefore, these data are often indirectly acquired by utilizing allometric length-biomass relationships based on a correlative parameter, such as body length. Previous studies have often used such relationships with a low taxonomic resolution and/or small sample size and/or adopted regressions calibrated in different biomes. Despite the scientific interest in the ecology of arctic arthropods, no site-specific family-level length-biomass relationships have hitherto been published. Here we present 27 family-specific length-biomass relationships from two sites in the High Arctic: Zackenberg in northeast Greenland and Knipovich in north Taimyr, Russia. We show that length-biomass regressions from different sites within the same biome did not affect estimates of phenology but did result in substantially different estimates of arthropod biomass. Estimates of daily biomass at Zackenberg were on average 24% higher when calculated using regressions for Knipovich compared to using regressions for Zackenberg. In addition, calculations of daily arthropod biomass at Zackenberg based on order-level regressions from frequently cited studies in literature revealed overestimations of arthropod biomass ranging from 69.7% to 130% compared to estimates based on regressions for Zackenberg. Our results illustrate that the use of allometric relationships from different sites can significantly alter the biological interpretation of, for instance, the interaction between insectivorous birds and their arthropod prey. We conclude that length-biomass relationships should be locally established rather than being based on global relationships.


Assuntos
Artrópodes , Ecossistema , Humanos , Animais , Biomassa , Estatura , Eulipotyphla
5.
PLoS One ; 18(8): e0288280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37616252

RESUMO

The Hawaiian hoary bat (Lasiurus semotus; Chiroptera: Vespertilionidae), commonly and locally known as 'ope'ape'a, is a solitary, insectivorous, and foliage-roosting species distributed across a wide range of habitats in lowland and montane environments. The species, as with many others in the Hawaiian archipelago, are facing a suite of challenges due to habitat loss and degradation, introduced predators and pests, and climate change. An understanding of the roost requirements of foliage-roosting tree bats is critical to their conservation as these habitats provide several important benefits to survival and reproduction. Because little is known about 'ope'ape'a roost ecology and considerable effort is needed to capture and track bats to roost locations, we examined resource selection at multiple spatial scales-perch location within a roost tree, roost tree, and forest stand. We used a discrete choice modeling approach to investigate day-roost selection and describe attributes of roost trees including those used as maternity roosts. 'Ope'ape'a were found roosting in 19 tree species and in an assortment of landcover types including native and non-native habitats. Our results are largely consistent with findings of other studies of foliage-roosting, insectivorous tree bats where bats selected roost locations that may offer protection and thermoregulatory benefits.


Assuntos
Quirópteros , Animais , Feminino , Humanos , Gravidez , Regulação da Temperatura Corporal , Mudança Climática , Eulipotyphla , Havaí , Poaceae , Árvores
6.
Genes (Basel) ; 14(7)2023 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-37510398

RESUMO

The Indian highland shrew, Suncus niger (Horsfield, 1851), is the least studied soricid species from its original range distribution in Southern India, with several systematics conundrums. Following its discovery in 1851, the species was synonymized with Suncus montanus (Kelaart, 1850) (endemic to Sri Lanka) and subsequently identified as a separate Indian population. However, the systematic status of S. niger from topotype specimens in Southern India has yet to be determined through an integrated approach. Both taxonomy and mitochondrial genetic data (Cytochrome b and 16S ribosomal RNA) were used to re-examine the systematics of S. niger. The mtCytb gene clearly distinguished topotypic S. niger from other Suncus species, with high genetic divergences varying from 8.49% to 26.29%. Further, the Bayesian and maximum likelihood topologies clearly segregated S. niger from other congeners and corroborated the sister relationship with S. stoliczkanus with expected divergence in the late Pliocene (2.62 MYA). The TimeTree analysis also exhibits a strong matrilineal affinity of S. dayi (endemic to India) toward the African species. The current study hypothesizes that the ancestor of the soricids evolved in Africa and that genetic lineages were subsequently shifted by plate tectonic events that subsequently colonized different continents as distinct species during the late Miocene (Tortonian) to the Holocene era. In addition to the new range expansion and elevation records of S. niger in the Central Western Ghats, we propose that additional sampling across its distribution, as well as the use of multiple genetic markers, may be useful in determining the genetic diversity and population structure of this endemic species. The present study also recommends that more molecular data on the Soricomorphs lineages, and estimates of their divergence times, will shed light on the evolution of these small mammals on Earth.


Assuntos
Eulipotyphla , Musaranhos , Animais , Musaranhos/genética , Filogenia , Níger , Teorema de Bayes , Biodiversidade , Índia
7.
Zootaxa ; 5263(1): 61-78, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37044999

RESUMO

The Himalayan shrew, Soriculus nigrescens Gray, 1842, belongs to the monotypic genus Soriculus, which is distributed mainly in the Himalayan region. Previous authors have studied its classification based on morphological and molecular data. However, no comprehensive study of the diversity and phylogeny of this species has been performed. In this study, we investigated the molecular phylogeny, genetic diversity, and species divergence of S. nigrescens based on one mitochondrial gene and three nuclear genes. A total of 124 samples from 27 sites in Southwest China were analyzed. Our molecular phylogenetic analyses and species divergence reveal non-monophyly of Soriculus, potentially representing two genera and three clades. Populations from Yunnan (Clade YN) represent the subspecies S. n. minors and should recover the full species status. Populations from Himalayas (Clade A) represent the species S. nigrescens, while populations from southeastern Nyenchen Tanglha Mountains and southern Himalayas (Clade B) represent a new cryptic and unnamed species. Species delimitation analyses and deep genetic distance analysis clearly support the species status of these three evolving clades. The putative new genus and cryptic species should be studied and identified in the future using a more extensive sampling combined with a comprehensive morphological and phylogenetic analysis.


Assuntos
Eulipotyphla , Musaranhos , Animais , Filogenia , Musaranhos/genética , Eulipotyphla/genética , China , DNA Mitocondrial/genética , Teorema de Bayes
8.
J Parasitol ; 109(1): 21-26, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36808923

RESUMO

The eastern mole, Scalopus aquaticus (L.), is a common inhabitant of loamy soils in Canada, the eastern United States, and Mexico. Seven coccidian parasites have been previously reported from S. aquaticus, including 3 cyclosporans and 4 eimerians from hosts taken in Arkansas and Texas. A single S. aquaticus, collected in February 2022 in central Arkansas, was found to be passing oocysts of 2 coccidians, a new species of Eimeria, and Cyclospora yatesiMcAllister, Motriuk-Smith, and Kerr, 2018. Oocysts of Eimeria brotheri n. sp. are ellipsoidal (sometimes ovoidal) with a smooth bilayered wall, measure 14.0 × 9.9 µm, and have a length/width (L/W) ratio of 1.5; both micropyle and oocyst residua are absent, but a single polar granule is present. Sporocysts are ellipsoidal and measure 8.1 × 4.6 µm, L/W 1.8; a flattened to knoblike Stieda body as well as a rounded sub-Stieda body are present. The sporocyst residuum is composed of an irregular mass of large granules. Additional metrical and morphological information is provided on oocysts of C. yatesi. This study demonstrates that although several coccidians were previously documented from this host, additional S. aquaticus should be examined for coccidians from Arkansas as well as other parts of its range.


Assuntos
Coccidiose , Cyclospora , Eimeria , Animais , Eulipotyphla , Arkansas , Oocistos , Coccidiose/parasitologia , Fezes/parasitologia
9.
J Exp Biol ; 226(3)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688286

RESUMO

The star-nosed mole (Condylura cristata) is renowned for its densely innervated 22 appendage star-like rostrum ('star') specialized for tactile sensation. As a northerly distributed insectivorous mammal exploiting aquatic and terrestrial habitats, these vascularized nasal rays are regularly exposed to cold water and thermally conductive soil, leading us to ask whether the star surface temperature, a proxy for blood flow, conforms to the local ambient temperature to conserve body heat. Alternatively, given the exquisite sensory nature of the star, we posited that the uninsulated rays may be kept warm when foraging to maintain high mechanosensory function. To test these hypotheses, we remotely monitored surface temperatures in wild-caught star-nosed moles. Although the tail acted as a thermal window exhibiting clear vasoconstriction/vasodilation, the star varied passively in surface temperature, with little evidence for thermoregulatory vasomotion. This thermoconforming response may have evolved to minimize conductive heat loss to the water or wet soils when foraging.


Assuntos
Toupeiras , Animais , Toupeiras/fisiologia , Eulipotyphla , Nariz , Tato/fisiologia , Regulação da Temperatura Corporal/fisiologia , Solo
10.
Integr Zool ; 18(3): 469-492, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36054534

RESUMO

The spatial genetic structure is a topical issue in the studies of various aspects of ecology and evolution. Using the multilocus autocorrelation method with hypervariable microsatellite genetic markers, we investigated a fine-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300-1000 m (the Moscow chromosomal race). Spatial genetic autocorrelation analysis based on 5 microsatellite loci (expected heterozygosity >0.79) with 90 alleles revealed a consistent pattern of significant positive genetic structure. By testing the autocorrelation at multiple scales from 25 to 500 m, we found that positive spatial genetic structure is detectable in distance classes of <500 m. The weaker spatial genetic structure positively correlated with a higher ratio of nonresident individuals to residents' activity (number of captures). In contrast to nonresident animals, the residents demonstrated prominent genetic structure. Genetic difference (FST ) between the populations was significant (0.016-0.051) and comparable with that between populations of different races analyzed previously (0.016-0.038). FST was not associated with geographic distance. These demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic profiles from а common pool where the alleles are mixed. The scheme predicts fluctuating genetic structure and random similar differences among local populations.


Assuntos
Eulipotyphla , Musaranhos , Animais , Musaranhos/genética , Eulipotyphla/genética , Repetições de Microssatélites/genética , Variação Genética
11.
Zootaxa ; 5339(1): 59-78, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-38221066

RESUMO

A new medium-sized shrew mole species of the genus Uropsilus from Mount Fansipan, Hoang Lien National Park, Lao Cai Province, northwestern Vietnam is described based on morphological and molecular differences. Uropsilus fansipanensis sp. nov. is distinguished from the other Uropsilus species by the combination of the following features: the dorsum is lightly reddish-brown and venter is dark gray; the dark gray tail is long and slender, with a scattered white base and short bristle hairs; orbital process is oriented upwards posteriorly; lacrimal foramen is well developed and much larger than infraorbital foramen; the lower first premolar is approximately the same size as the lower third premolar. Genetic distances in terms of mitochondrial cytochrome b from other Uropsilus species presented pairwise divergences from 8.63 to 20.70%. To date, the new species is known to exist only in the type locality of Mt. Fansipan, a wet and cold temperate climate area with an upper montane forest at an elevation of approximately 2900 m, forming the southernmost distribution of the genus Uropsilus.


Assuntos
Eulipotyphla , Toupeiras , Animais , Filogenia , Musaranhos , Vietnã , Toupeiras/genética
12.
PLoS One ; 17(9): e0274637, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36149843

RESUMO

Edge effects, abiotic and biotic changes associated with habitat boundaries, are key drivers of community change in fragmented landscapes. Their influence is heavily modulated by matrix composition. With over half of the world's tropical forests predicted to become forest edge by the end of the century, it is paramount that conservationists gain a better understanding of how tropical biota is impacted by edge gradients. Bats comprise a large fraction of tropical mammalian fauna and are demonstrably sensitive to habitat modification. Yet, knowledge about how bat assemblages are affected by edge effects remains scarce. Capitalizing on a whole-ecosystem manipulation in the Central Amazon, the aims of this study were to i) assess the consequences of edge effects for twelve aerial insectivorous bat species across the interface of primary and secondary forest, and ii) investigate if the activity levels of these species differed between the understory and canopy and if they were modulated by distance from the edge. Acoustic surveys were conducted along four 2-km transects, each traversing equal parts of primary and ca. 30-year-old secondary forest. Five models were used to assess the changes in the relative activity of forest specialists (three species), flexible forest foragers (three species), and edge foragers (six species). Modelling results revealed limited evidence of edge effects, except for forest specialists in the understory. No significant differences in activity were found between the secondary or primary forest but almost all species exhibited pronounced vertical stratification. Previously defined bat guilds appear to hold here as our study highlights that forest bats are more edge-sensitive than edge foraging bats. The absence of pronounced edge effects and the comparable activity levels between primary and old secondary forests indicates that old secondary forest can help ameliorate the consequences of fragmentation on tropical aerial insectivorous bats.


Assuntos
Quirópteros , Floresta Úmida , Animais , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Eulipotyphla , Florestas , Árvores
13.
J Hum Evol ; 170: 103238, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35988384

RESUMO

Small mammals (insectivores, rodents, and lagomorphs) from Dmanisi are here reviewed for the first time and used as a tool for paleoenvironmental proxies. The small mammal faunal list is composed of shrews (Beremendia fissidens, cf. Beremendia minor, Crocidura kornfeldi), hamsters (Cricetulus sp., Allocricetus bursae), gerbils (Parameriones aff. obeidiyensis), murids (Apodemus cf. atavus), arvicolids (Mimomys pliocaenicus, Mimomys aff. pusillus), and pikas (Ochotona sp.). A paleoenvironmental reconstruction based on the habitat weighting method has been applied to the rodent assemblage. According to this method, the most common elements indicate an open-dry habitat (36.5%), followed by water edge (25.7%) and rocky (21.0%) elements. Open-wet (15.5%) and woodland elements (1.3%) are rare. Therefore, the habitat occupied by the hominids of Dmanisi was characterized by the prevalence of arid conditions, from steppe or semi-desert to open Mediterranean forest, with stony or rocky substrate and bushy areas. The presence of permanent aquatic environments is also documented. From a biogeographic point of view, the small mammal community from Dmanisi is composed mainly by Western or Central Asian elements, with a poor representation of European elements (Mimomys, Apodemus). It is concluded that Dmanisi hominins most possibly had ecological requirements which were different from those of the Early Pleistocene hominins from Western Europe, which settled on wetter habitats. It could be also possible that Dmanisi hominins entered Southern Caucasus at an interglacial phase before the deposition of the Dmanisi site.


Assuntos
Hominidae , Lagomorpha , Animais , Eulipotyphla , Fósseis , República da Geórgia , Murinae , Roedores
14.
Proc Natl Acad Sci U S A ; 119(33): e2203663119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35939677

RESUMO

Animals that depend on ephemeral, patchily distributed prey often use public information to locate resource patches. The use of public information can lead to the aggregation of foragers at prey patches, a mechanism known as local enhancement. However, when ephemeral resources are distributed over large areas, foragers may also need to increase search efficiency, and thus apply social strategies when sampling the landscape. While sensory networks of visually oriented animals have already been confirmed, we lack an understanding of how acoustic eavesdropping adds to the formation of sensory networks. Here we radio-tracked a total of 81 aerial-hawking bats at very high spatiotemporal resolution during five sessions over 3 y, recording up to 19 individuals simultaneously. Analyses of interactive flight behavior provide conclusive evidence that bats form temporary mobile sensory networks by adjusting their movements to neighboring conspecifics while probing the airspace for prey. Complementary agent-based simulations confirmed that the observed movement patterns can lead to the formation of mobile sensory networks, and that bats located prey faster when networking than when relying only on local enhancement or searching solitarily. However, the benefit of networking diminished with decreasing group size. The combination of empirical analyses and simulations elucidates how animal groups use acoustic information to efficiently locate unpredictable and ephemeral food patches. Our results highlight that declining local populations of social foragers may thus suffer from Allee effects that increase the risk of collapses under global change scenarios, like insect decline and habitat degradation.


Assuntos
Quirópteros , Eulipotyphla , Comportamento Predatório , Animais , Quirópteros/fisiologia , Ecolocação , Ecossistema , Eulipotyphla/fisiologia , Voo Animal , Comportamento Predatório/fisiologia
15.
Mol Phylogenet Evol ; 177: 107619, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36007821

RESUMO

The striped-back shrew group demonstrates remarkable variation in skull and body size, tail length, and brightness of the dorsal stripe; and karyotypic and DNA variation has been reported in recent years. In this study, we investigated the phylogenetic structure of the group, as well as speciation patterns and demographic history in Mountains of Southwestern China and adjacent mountains, including the southern Himalayas, Mts. Bashan, Wushan, and Qinling. We sequenced a total of 462 specimens from 126 localities in the known range of the group, which were sequenced and analyzed based on 6.2 kb of sequence data from two mitochondrial, six nuclear, and two Y chromosome markers. Phylogenetic analyses of the concatenated mtDNA data revealed 14 sympatric and independently evolving lineages within the striped-back shrew group, including Sorex bedfordiae, S. cylindricauda, S. excelsus, S. sinalis and several cryptic species. All concatenated data (ten genes) showed a consistent genetic structure compared to the mtDNA lineages for the group, whereas the nuclear and the Y chromosome data showed a discordant genetic structure compared to the mtDNA lineages for the striped-back shrew group. Species delimitation analyses and deep genetic distance clearly support the species status of the 14 evolving lineages. The divergence time estimation suggested that the striped-back shrew group began to diversify from the middle Pleistocene (2.34 Ma), then flourished at approximately 2.14 Ma, followed by a series of rapid diversifications through the Pleistocene. Our results also revealed multiple mechanisms of speciation in the Mountains of Southwestern China and Adjacent Mountains with complex landscapes and climate. The uplifting of the Qinghai-Tibetan Plateau, Quaternary climate oscillations, riverine barriers, ecological elevation gradients, topographical diversity, and their own low dispersal capacity may have driven the speciation, genetic structure, and phylogeographic patterns of the striped-back shrew group.


Assuntos
Eulipotyphla , Musaranhos , Animais , DNA Mitocondrial/genética , Marcadores Genéticos , Variação Genética , Filogenia , Musaranhos/genética
16.
Sci Rep ; 12(1): 4964, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322145

RESUMO

During their annual migration, avian migrants alternate stopover periods, for refuelling, with migratory flight bouts. We hypothesise that European Nightjars (Caprimulgus europaeus) adapt their daily migration tactics in association with biomes. We tracked the autumn migration of 24 European Nightjars, from breeding populations in Mongolia, Belgium and UK, using GPS-loggers and multi-sensor data loggers. We quantified crepuscular and nocturnal migration and foraging probabilities, as well as daily travel speed and flight altitude during active migration in response to biomes. Nightjars adopt a rush tactic, reflected in high daily travel speed, flight altitude and high migration probabilities at dusk and at night, when travelling through ecological barriers. Migration is slower in semi-open, hospitable biomes. This is reflected in high foraging probabilities at dusk, lower daily travel speed and lower migration probabilities at dusk. Our study shows how nightjars switch migration tactics during autumn migration, and suggest nightjars alternate between feeding and short migratory flight bouts within the same night when travelling through suitable habitats. How this may affect individuals' fuel stores and whether different biomes provide refuelling opportunities en route remains to be investigated, to understand how future land-use change may affect migration patterns and survival probabilities.


Assuntos
Migração Animal , Estrigiformes , Altitude , Migração Animal/fisiologia , Animais , Ecossistema , Eulipotyphla , Humanos , Estações do Ano
17.
Sci Rep ; 11(1): 24496, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34969948

RESUMO

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.


Assuntos
Eulipotyphla/genética , Animais , China , Feminino , Variação Genética , Cariótipo , Masculino , Filogenia , Tibet
18.
J Exp Biol ; 224(19)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34533564

RESUMO

Star-nosed moles (Condylura cristata) have an impressive diving performance and burrowing lifestyle, yet no ventilatory data are available for this or any other talpid mole species. We predicted that, like many other semi-aquatic and fossorial small mammals, star-nosed moles would exhibit: (i) a blunted (i.e. delayed or reduced) hypoxic ventilatory response, (ii) a reduced metabolic rate and (iii) a lowered body temperature (Tb) in hypoxia. We thus non-invasively measured these variables from wild-caught star-nosed moles exposed to normoxia (21% O2) or acute graded hypoxia (21-6% O2). Surprisingly, star-nosed moles did not exhibit a blunted HVR or decreased Tb in hypoxia, and only manifested a significant, albeit small (<8%), depression of metabolic rate at 6% O2 relative to normoxic controls. Unlike small rodents inhabiting similar niches, star-nosed moles are thus intolerant to hypoxia, which may reflect an evolutionary trade-off favouring the extreme sensory biology of this unusual insectivore.


Assuntos
Mergulho , Toupeiras , Animais , Temperatura Corporal , Eulipotyphla , Hipóxia
19.
Am J Physiol Regul Integr Comp Physiol ; 321(4): R614-R624, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34431404

RESUMO

Many mammals use adaptive heterothermy (e.g., torpor, hibernation) to reduce metabolic demands of maintaining high body temperature (Tb). Torpor is typically characterized by coordinated declines in Tb and metabolic rate (MR) followed by active rewarming. Most hibernators experience periods of euthermy between bouts of torpor during which homeostatic processes are restored. In contrast, the common tenrec, a basoendothermic Afrotherian mammal, hibernates without interbout arousals and displays extreme flexibility in Tb and MR. We investigated the molecular basis of this plasticity in tenrecs by profiling the liver proteome of animals that were active or torpid with high and more stable Tb (∼32°C) or lower Tb (∼14°C). We identified 768 tenrec liver proteins, of which 50.9% were differentially abundant between torpid and active animals. Protein abundance was significantly more variable in active cold and torpid compared with active warm animals, suggesting poor control of proteostasis. Our data suggest that torpor in tenrecs may lead to mismatches in protein pools due to poor coordination of anabolic and catabolic processes. We propose that the evolution of endothermy leading to a more realized homeothermy of boreoeutherians likely led to greater coordination of homeostatic processes and reduced mismatches in thermal sensitivities of metabolic pathways.


Assuntos
Evolução Biológica , Metabolismo Energético , Eulipotyphla/metabolismo , Fígado/metabolismo , Proteoma , Termogênese , Torpor , Animais , Cromatografia de Fase Reversa , Feminino , Hibernação , Masculino , Proteômica , Proteostase , Espectrometria de Massas em Tandem
20.
J Zoo Wildl Med ; 52(2): 858-862, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130437

RESUMO

A 1-y-old female southern tamandua (Tamandua tetradactyla) presented with vomiting, hyporexia, and neurologic signs. Magnetic resonance imaging revealed contrast-enhancing material within the lateral and fourth ventricles and a T2 hyperintense cerebellar lesion, consistent with meningoencephalitis. The tamandua rapidly declined and was euthanatized. On gross postmortem exam, the tamandua had diffusely injected leptomeninges, opaque fluid in the fourth ventricle, and subdural brainstem and spinal cord hemorrhage. Histologically, there was regionally hemorrhagic and multifocal fibrinosuppurative meningoencephalomyelitis, ventriculitis, choroid plexitis, cerebellar folia necrosis, ependymitis, radiculoneuritis, and abundant intralesional gram-positive cocci. Streptococcus equi ssp. zooepidemicus was cultured from brain, cardiac blood clot, and multiple samples of horsemeat collected from the animal's diet. This is the first report of streptococcal meningoencephalomyelitis in a southern tamandua. The route of infection was likely gastrointestinal inoculation, which may have implications for the routine practice of feeding diets containing raw meat to insectivores.


Assuntos
Ração Animal/microbiologia , Encefalomielite/veterinária , Eulipotyphla , Carne/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus equi/isolamento & purificação , Animais , Dieta/veterinária , Encefalomielite/microbiologia , Encefalomielite/patologia , Evolução Fatal , Feminino , Microbiologia de Alimentos , Cavalos , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
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