Search Results (71)

Bats, as key ecological players, interact with a diverse array of organisms and perform essential roles in ecosystems, including pollination, pest control, and seed dispersal. However, their populations face significant threats from habitat contamination, particularly from microplastics (MPs). This study introduces a novel, efficient, and cost-effective method for visualizing transparent microplastics using ultraviolet (UV) light. By employing handheld UV flashlights with a wavelength range of 312 to 400 nm, we enhance the detection of MPs that may otherwise go unnoticed due to color overlap with filtration membranes. All necessary precautions were taken during sampling and analysis to minimize the risk of contamination and ensure the reliability of the results. Our findings demonstrate that the application of UV light significantly improves the visualization and identification of MPs, particularly transparent fibers. This innovative approach contributes to our understanding of plastic contamination in bat habitats and underscores the importance of monitoring environmental pollutants to protect bat populations and maintain ecosystem health. Full article

Trogopterus xanthipes (Sciuridae, Rodentia) is a medium-sized flying squirrel species in the monotypic genus Trogopterus, and is endemic to China. It is distinguishable from other squirrels by the long black hairs on the inner and outer sides at the base of the ears and numerous ridges on the crowns of the upper and lower cheek teeth. Mitogenomes have been widely used in phylogenetic studies. We described T. xanthipes morphological features and successfully sequenced its mitogenome for the first time. The T. xanthipes mitogenome was conserved in number and order of genes. We analyzed codon usage patterns, evolutionary mutation rates, K2P distance, and genetic diversity of protein-coding genes. We reconstructed the phylogeny of Sciuridae (94 species and 21 genera in 4 subfamilies). All phylogenetic trees shared the same topologies and consistently supported the monophyly of Sciuridae, and the supported subfamilies relationship as follows: ((Xerinae + Callosciurinae) + Sciurinae) + Ratufinae. The relationship within the Sciurinae clade was ((Glaucomys + Hylopetes) + ((Trogopterus+Pteromys) + Petaurista) + Sciurus). The relationship within the Callosciurinae clade was Exilisciurus + ((Tamiops + Dremomys) + ((Lariscus+Sundasciurus) + Callosciurus)). The relationship within the Xerinae clade was Sciurotamias + (Tamias + (Callospermophilus + (Marmota + (Spermophilus + (Urocitellus + (Ictidomys + Cynomys)))))). The phylogenetic position among different subfamilies of Sciuridae was consistently recovered with high support across different datasets (PCGRNA and PCG12RNA) and supported the monophyletic lineage of each genus of Sciuridae. Trogopterus xanthipes was sister species to Pteromys volans. Species within the genus formed different minor clades, suggesting relatively high interspecific divergences. The tribe Pteromyini was sister taxon of the tribe Sciurini, which was not supported by the traditional division of Sciuridae into subfamilies Pteromyinae and Sciurinae. Hence, our data supported a division of the Sciuridae into five subfamilies. Full article

Antimicrobial resistance (AMR) is a significant global challenge that affects environmental, animal, and human health, with reports of antimicrobial-resistant bacteria and antimicrobial resistance genes becoming increasingly common across these domains. This study aimed to systematically review and compare the occurrence of AMR in bacterial isolates from wild animals in South America, focusing on environments with varying levels of anthropogenic impact. Half of the countries in South America documented AMR in wild animals at least once. Most studies focused on specific animal classes, particularly Aves and Mammalia, with a notable emphasis on the orders Chiroptera and Rodentia, as well as the bacterial species Escherichia coli and Salmonella enterica. Subgroup meta-analyses revealed that, for most antimicrobials, the proportion of AMR was significantly higher in environments with a high anthropogenic impact compared to those with a low anthropogenic impact. However, there were no significant differences between the two types of environments for some antimicrobials. Interestingly, certain beta-lactams showed a higher proportion of AMR in environments with low anthropogenic impact. These findings raise important questions regarding the origins and spread of AMR in wild animals, underscoring the necessity for further research to understand the dynamics of AMR in areas with varying levels of human intervention. Full article

Hedgehogs are small omnivorous mammals prevalent across Europe, Asia, and Africa. The expanding intrusion of humans into hedgehog habitats and rising popularity of keeping exotic animals like hedgehogs as pets have disrupted the delicate balance of the human–animal–environment interface. Despite their ecological importance, hedgehog-borne flea species have received limited research attention, with most studies focusing on their vectorial role, and except one report, nothing on the species composition and genetic diversity of hedgehog flea specimens. An inventory and phylogenetic investigation, conducted for the first time in Algeria as well as in North Africa, allowed for collecting 45 hedgehogs (15 males and 30 females) and 303 fleas, and analyzing them through morphological and molecular approaches. The hedgehog specimens were subjected to macro- and microscopic examinations based on diagnostic morphological criteria and morphometric measurements, resulting in their identification as Atelerix algirus. This study represents the first report of this species’ prevalence in Djelfa. The ecological and geographical diversity of the studied areas, from arid deserts to humid regions, highlights the adaptability and resilience of A. algirus to diverse habitats. Additionally, 271 and 32 flea specimens were morphologically identified as Archaeopsylla erinacei and Ctenocephalides felis, respectively. Molecular examination targeting ITS1-rDNA further confirmed the morphological identification of fleas species. Phylogenetic analysis of fleas’ ITS1-rDNA sequences revealed heterogeneity, with the specimens clustering into two distinct clades. The first clade comprised two populations of A. erinacei, while the second clade included C. felis specimens of this study, grouped with homologous sequences from various regions worldwide. No correlation between flea species and geographical locations was observed demonstrating the sympatric distribution of flea specimens in the studied regions. In addition, no hybrid or genetic combination notion was observed among the flea specimens processed in this study compared with those coming from other countries. These findings contribute to our understanding of the species composition and distribution of hedgehogs and their flea ectoparasites in Algeria and provide a baseline for future epidemiological and entomological research in the country. Full article

Milk is the principal nutrient of newborn humans and a diagnostic feature of the order Mammalia. Its release is elicited as a reflex by infant sucking under the control of the hormone oxytocin. While it is recognized that breast milk optimally promotes infant longitudinal growth and development, this review explores facts and controversies regarding the extent to which the milks of several dairy animals and infant formula milk (IF) approximate special properties and bioactivities of breast milk. It also provides evidence that early exposure to undernutrition during the very rapid fetal and early infancy growth predominantly and permanently stunts longitudinal growth trajectory in both animals and humans and is often followed in later life by obesity and metabolic dysfunction, and sometimes also by precocious timing of sexual maturation. There is a knowledge gap as to whether there may be additional critical periods of nutritional vulnerability in human development, which is characterized by a relatively prolonged period of slow childhood growth bracketed by the rapid fetal–neonatal and pubertal growth spurts. It is also unclear whether any quantitative differences in caloric intake and supply during neonatal period may influence developmental fatness programming. A further knowledge gap exists regarding the role of infant microbiome composition and development in the possible epigenetic programming of longitudinal growth or fatness in later life. Extending the research of early developmental programming to the entire period of human growth from conception to the end of puberty, examining infant caloric intake and supply as possible factors modulating the epigenetic programming in favor of obesity, and examining the role of infant gut microbiome in developing infant’s capacity to process nutrients may provide a better understanding of the interaction between critical nutritional influences in the control of human longitudinal growth and later-life obesity. Full article

This study investigated the infection rates of intestinal parasites in captive wild animals from 2000 to 2024 and analyzed the associated risk factors using a meta-analysis. We retrieved 29 studies, with a total of 8421 captive wild mammals, published between 2000 and 2024. We used the DerSimonian-Laird model and calculated infection rate estimates with the variance stabilizing double arcsine transformation. The results revealed that the overall prevalence of gastrointestinal parasitic infections in captive wild mammals in mainland China was found to be 53.9%. The highest infection rate was observed for nematodes at 45.1%. Seasonal subgroup analysis revealed the highest incidence in summer at 61.8% and 61.6% in winter. In the class order Mammalia, the highest infection rate was found in the Primates at 66.5% and similarly high values were determined in several other orders like Artiodactyla (59%), Rodentia (57.1%), Carnivora (53.3%) and extremely low in Proboscidea (19.9%). The highest overall infection rate was recorded in summer. The infection rate of gastrointestinal parasites in captive wild mammals in mainland China is notably high. Additionally, parasitic infection rates in captive animals were found to be lower in economically developed regions of mainland China. Full article

According to the “suid gap” hypothesis, suids (Suidae, Mammalia) would have been absent from Europe between 1.8 and 1.2 Ma. This hypothesis has been influential owing to its putative implications for biochronology and paleoecology—Sus scrofa (the modern wild boar) would appear 1.2 Ma in a period of climatic and environmental changes, coinciding with the beginning of the Epivillafranchian and the Early–Middle Pleistocene Transition, and hominins—the arrival of Homo in western Europe would precede the “return” of pigs. However, the “suid gap” hypothesis is based on the wrong premises that suids are abundantly represented in the European fossil record before and after the “suid gap”, that this purported abundance is linked to the suid reproductive potential, and that the paleontological sites dated within the 1.8–1.2 Ma interval yielded enough remains to exclude the notion that the absence of suid is merely accidental. In a recent paper, it is shown that all these assumptions are erroneous and suid material is described from Peyrolles (France), which is dated at 1.47 ± 0.01 Ma, hence perfectly “filling the suid gap”. Some proposers of the “suid gap” hypothesis have now provided comments to this recent paper, casting doubt on the age of Peyrolles and reiterating the arbitrary statement that suids were commonly recorded and abundantly represented in the Pleistocene of Europe. There is no valid reason to question the homogeneity of the faunal assemblage of Peyrolles, which is indeed a key locality for the mammal biochronology of Europe, being the reference for MNQ 19. Suids of comparable chronology have also been found in Krimni (Greece). Moreover, the “suid gap” proposers are basically advocating the use of an interval biozone based on the temporary absence of Sus strozzii—a species not common in the Pleistocene of Europe—providing no ecological explanation for this gap, apart from speculating it would be due to competition with Homo. The defense of the “suid gap” seems motivated by its use from the “suid gap” proposers as a biochronological argument to contend that the localities of Orce in Spain (Barranco León D, Fuente Nueva 3, and Venta Micena) are older than 1.2 Ma, when they postulated suids would “reappear” in the fossil record. However, since the “suid gap” hypothesis was primarily proposed based on the absence of suids from the Orce sites (and, secondarily, from other sites biochronologically correlated with the localities of Orce, like Pirro Nord in Italy), this represents an evident example of circular reasoning. Full article

We assembled and annotated the complete mitochondrial genomes of Lycalopex vetulus (hoary fox), Cerdocyon thous (bush dog), Tayassu pecari (white-lipped peccary), and Tadarida brasiliensis (Brazilian free-tailed bat). The mitogenomes exhibited typical vertebrate structures, containing 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes, and a D-loop region. Phylogenetic reconstruction using the 13 protein-coding genes revealed robust relationships among species within Carnivora, Chiroptera, and Artiodactyla, corroborating previous studies. Secondary structure analysis of tRNAs and ribosomal genes showed slight variations among species of the same order. This research highlights the importance of mitochondrial genomics in understanding the evolutionary relationships and genetic diversity of Cerrado mammals, contributing to conservation efforts for this unique ecosystem. Full article

This study employs Principal Component Analysis to examine cranial measurements from both extant and fossil specimens spanning 38 species and comprising over 300 individuals within the subfamily Cervinae. Our findings elucidate craniometric distinctions among cervids characterized by varying body sizes and certain evolutionary adaptations. While our results generally corroborate previous assertions regarding the limited craniometric variability among plesiometacarpal deer, they also unveil specific cranial adaptations within certain genera and species. The Principal Component Analysis of craniometric data revealed that giant and large-sized deer display significantly broader ecomorphological diversity in cranial shape compared to small-sized deer. Secondly, small-sized deer exhibit greater uniformity in their cranial shape, appearing densely clustered on the factorial map. Thus, we conclude that body size imposes ecological constraints, limiting the available niches due to eco-physiological factors. This study demonstrates that endemic insular deer do not evolve consistent craniometric features attributable to insular isolation, while the cranial proportions of medium-to-small-sized deer delineate a ubiquitous morphological archetype characteristic of numerous cervid taxa spanning diverse phylogenetic lineages and sharing comparable body sizes. This group of “Dama-like” deer, characterized by similar body size, metabolic rates, ecological needs, and cranial morphometry, is referred to here as the fundamental eco-physiological type, typical of warm regions within the Palearctic and Oriental biogeographic realms. Full article

The grey-shanked douc langur (Pygathrix cinerea) is a recently described, critically endangered primate, endemic to Vietnam. In this study, we describe the Central Highland species’ complete mitochondrial genome (mitogenome—mtDNA). It is a circular molecule with a length of 16,541 base pairs (bp). The genome consists of 37 genes, consistent with those found in most other vertebrates, including 13 protein coding genes, 22 transfer RNAs, and two ribosomal RNAs. A comparison with the mitogenomes of more than 50 primates showed that the mitogenome of Vietnamese Central Highland Pygathrix cinerea has a conservative gene order. We identified 43 nucleotide differences when comparing this genome with a previously published mitogenome of Pygathrix cinerea. It is evident that there are distinct differences between the Pygathrix cinerea we are currently studying and other Pygathrix cinerea specimens. These differences are unlikely to be solely the result of sequencing errors, as the mitogenomes were generated using high-quality methods. The genetic divergence observed between the two Pygathrix cinerea mitogenomes implies the potential existence of at least two distinct lineages or forms of this primate species within its native range in Vietnam. Full article

Coronodon includes species of basal toothed mysticetes that were initially interpreted as engaging in raptorial feeding and dental filtration. Here, the feeding of this extinct genus is revisited based on recently described specimens and species. Associations between tooth position and types of dental wear were tested, and evidence for feeding behaviors was tabulated using scores from 14 craniodental characters, each mapped onto five alternate phylogenetic hypotheses. Individual character states were interpreted as being supportive, neutral, or contradictory evidence to raptorial feeding, suction feeding, baleen filtration, or dental filtration. Wear in Coronodon was found to be significantly more concentrated on mesial teeth, mesial cusps, higher cusps, and upper teeth. Upper teeth also had mesial cusps more worn than distal cusps, inconsistent with predictions of the dental filtration hypothesis. Wear in notches was correlated with wear on neighboring cusps, and side wear was concentrated on occlusal sides, suggesting both were caused by raptorial feeding. These observations raise the possibility that raptorial feeding was the primary, and maybe even the only, mode of feeding for Coronodon. The feeding scores of reconstructed ancestors leading to crown mysticetes typically display a stepwise decrease in raptorial feeding, a stepwise increase in baleen filtration, and, occasionally, an intermediate but weakly supported stage of dental filtration. For most toothed mysticetes, there is little evidence for or against suction feeding. The method we have developed for studying the origin of baleen can be expanded and allows for multiple hypotheses to be tested without undue emphasis on any particular taxon or set of characters. Full article

The young of toothed mammals must have teeth to reach feeding independence. How tooth eruption integrates with gestation, birth and weaning is examined in a life-history perspective for 71 species of placental mammals. Questions developed from high-quality primate data are then addressed in the total sample. Rather than correlation, comparisons focus on equivalence, sequence, the relation to absolutes (six months, one year), the distribution of error and adaptive extremes. These mammals differ widely at birth, from no teeth to all deciduous teeth emerging, but commonalities appear when infants transit to independent feeding. Weaning follows completion of the deciduous dentition, closest in time to emergence of the first permanent molars and well before second molars emerge. Another layer of meaning appears when developmental age is counted from conception because the total time to produce young feeding independently comes up against seasonal boundaries that are costly to cross for reproductive fitness. Mammals of a vast range of sizes and taxa, from squirrel monkey to moose, hold conception-to-first molars in just under one year. Integrating tooth emergence into life history gives insight into living mammals and builds a framework for interpreting the fossil record. Full article

Insectivores (Eulypotiphla) are a substantial component of Russian forest ecosystems. The parasites of these animals also form an important part of natural biocenoses and act as one of the factors in the formation of biodiversity. The Mordovia Nature Reserve and National Park “Smolny” are large, forested areas located in the center of European Russia. We studied the helminth fauna of insectivores in these protected areas in 2018–2022. In total, using the method of complete helminthological necropsy, we examined 478 individuals of shrews, moles, and hedgehogs and recorded 34 species of parasitic worms, i.e., 8 trematode, 7 cestode, 1 acanthocephalan, and 18 nematode species. The most diverse helminth fauna was found in Sorex araneus (22 species). The composition of helminths in S. isodon (12), Neomys fodiens (9), Sorex minutus, and Erinaceus roumanicus (8 species each) turned out to be less diverse. The lowest species diversity of helminths was observed in Neomys milleri (3) and Talpae europaea (2 species). Taking into account the newly obtained data, we conducted a review of the helminth diversity in shrews, hedgehogs, and moles in the Middle Volga region. According to our literature data, the helminth fauna of insectivores in this region consists of 52 species, including 14 cestodes, 13 trematodes, 22 nematodes, and 3 acanthocephalans. Most of them belong to the Palearctic faunal complex (36 species). The helminth fauna of insectivores in the studied protected areas was compared with the helminth fauna of micromammals in other areas of the Middle Volga region. Our comparative analysis showed a high and average degree of similarity in the helminth fauna within individual species and genera of Eulipotyphla. Full article

The causative agent of Chagas disease is Trypanosoma cruzi, which is widely distributed throughout the South American continent and extends into North America. Its occurrence in bats is poorly described and may impact the disease’s maintenance and epidemiology. The aim of this study was to detect the agent by PCR assays targeting kDNA and nuclear DNA in the organs of 203 urban bats and rural vampire bats from the Brazilian Atlantic Forest, São Paulo state, during the pandemic period from 2020 to 2022. In total, 6 of the 203 bats (2.97%) were positive for T. cruzi. Infection was detected in 2% (2/101) of Desmodus rotundus, 33% (1/3) of Nyctinomops laticaudatus, 25% (1/4) of Artibeus lituratus, 4% (1/24) of Eumops glaucinus and in 2% (1/41) of Molossus molossus. The gene sequences obtained were assessed for quality and deposited in a public repository. Fruit bats were statistically associated with positivity for T. cruzi. To our knowledge, this study detected T. cruzi for the first time in bats from São Paulo state and in N. laticaudatus and E. glaucinus species. Full article

Here, we document the stranding of a striped dolphin Stenella coeruleoalba (Meyen, 1833) (Mammalia: Delphinidae), which was found dead in Maltese waters in July 2020. The stranded dolphin exhibited a severe infestation of the mesoparasitic copepod, Pennella balaenoptera Koren and Danielssen, 1877 (Copepoda: Pennelidae). Parasites of this genus represent the largest known mesoparasites to infest cetaceans. Under normal circumstances, cetaceans may have a few P. balaenoptera individuals attached to them, but cetaceans with compromised health are more prone to heavy infestations. The identification of the parasite was accomplished through morphological and genetic analyses. This incident highlights the significance of monitoring mesoparasitic infestations, offering valuable insights into the health of cetacean populations and emphasizing the potential implications for conservation efforts in the region. Full article