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Background: The common opossum (Didelphis marsupialis) is a generalist species that hosts several parasites. Nevertheless, no information is available on the specific parasites that this species may host when it inhabits urban areas. Objective: To evaluate the presence and frequency of gastrointestinal parasites of urban opossums in the Aburrá Valley, Antioquia, Colombia. Methods: A total of 70 opossums were captured in six protected urban areas using Tomahawk traps during six months. From these animals we obtained 65 fecal samples which were fixed wit SAF solution and analyzed with direct smear and sedimentation techniques. Results: Sixty-one samples were positive for, at least, one parasite (93.9%) and 60 were positive for two or more parasites, averaging five parasites per animal. We observed nematodes in 58 samples (89.2%), protozoa in 46 samples (70.7%), acanthocephalans in 29 samples (44.6%), and cestodes in eight samples (12.3%). The most frequent parasite was Aspidodera spp. in 80% of the samples. In addition, this is the first study reporting the presence of eggs of Toxocara spp., Hymenolepis spp., an Oxyuridae parasite, and coccidians Eimeria didelphidis, E. caluromydis, and E. marmosopos in D. marsupialis. The latter is also reported in Colombia for the first time. Toxacara spp. is common to dogs and cats, while Hymenolepis and Oxiuridae are common to rodents. We found no association between parasites and sex or life stage of opossums, nor to the urban area of origin. Conclusions: Urban opossums in the Aburrá Valley host a high frequency and diversity of gastrointestinal parasites compared to other areas in Latin America. Some parasites are reported here for the first time. [ABSTRACT FROM AUTHOR]

The type II gonadotropin‐releasing hormone (GnRH‐II) was first discovered in chicken (Gallus gallus) brain and then shown to be present in many vertebrates. Indeed, its structure is conserved unchanged throughout vertebrate evolution from teleost fish through to mammals suggesting a crucial function. Yet the functional significance has been largely unexplored. Studies in comparative endocrinology show that the GnRH‐II system is differentially functional in mammalian species. Intact GnRH‐II neuropeptide and receptor genes (GnRH2 and GnRH receptor 2 GnRHR2) occur in marmoset monkeys (Callithrix jacchus), musk shrews (Suncus murinus) and pigs (Sus scrofa). However, one or other or both of these genes are inactivated in other species, where mutations or remnants affecting GnRH2 neuropeptide and/or type II GnRHR exons are retained in conserved genomic loci. New data from DNA sequencing projects facilitate extensive analysis of species‐specific variation in these genes. Here, we describe GnRH2 and GnRHR2 genes spanning a collection of 21 taxonomic orders, encompassing around 140 species from Primates, Scandentia, Eulipotyphla, Rodentia, Lagomorpha, Artiodactyla, Carnivora, Perissodactyls, Pholidota, Chiroptera, Afrotheria, Xenarthra and Marsupialia. Intact coding exons for both GnRH2 and GnRHR2 occur in monkeys, tree shrews, shrews, moles, hedgehogs, several rodents (degu, kangaroo‐rat, pocket mouse), pig, pecarry and warthog, camels and alpaca, bears, Weddell seal, hyena, elephant, aardvark and marsupials. Inactivating mutations affecting GnRH2 and GnRHR2, some located at conserved sites within exons, occur in species of primates, most rodents, lagomorphs, bovidae, cetaceans, felidae, canidae and other carnivora, pangolins, most bats, armadillo, brushtail and echidna. A functional GnRH‐II system appears retained within several taxonomic families of mammals, but intact retention does not extend to whole taxonomic orders. Defining how endogenous GnRH‐II neuropeptide operates in different mammals may afford functional insight into its actions in the brain, especially as, unlike the type I GnRH system, it is expressed in the mid brain and not the hypothalamus. [ABSTRACT FROM AUTHOR]

Opossums (marsupials of the Didelphidae family) retain a generalized masticatory apparatus and tribosphenic molars, often used as models to understand the evolution of mastication in early therian mammals. Like all marsupials, their growth goes through a stage when pups complete their development while permanently attached to the mother's teats before weaning and starting feeding on their own. Yet, while the masticatory muscles of adults are known, as is the ontogeny of the cranium and mandible, the ontogenetic changes in the masticatory muscles remain unknown. Here we describe for the first time the changes in the masticatory muscles observed in lactating pups, and weaned juveniles, subadults, and adults in the White‐eared opossum, Didelphis albiventris, through dissection of 25 specimens and quantification of relative muscle masses, lines of actions and mechanical advantages whenever possible. We also assessed the scaling patterns of muscle masses and mechanical advantages through ontogeny. The main changes, as expected, were found between suckling and weaned specimens, although some changes still occurred from juveniles to adults. The adult adductor musculature is similar to the other Didelphis species already known, with a dominant m. temporalis that originates on the lateral wall of the skull, up to the sagittal and nuchal crests, and fills the zygomatic arch when inserting into the lateral and medial surfaces of the coronoid process, respectively through the pars superficialis and pars profunda. The m. masseter is also subdivided in superficial and deep bundles which originate posteriorly in the maxilla and zygomatic arch, and insert into the angular process and masseteric fossa in the mandible. The m. pterygoideus medialis originates from the palatine, the pterygoid bone and the alisphenoid, and it inserts on the angular process medially. Suckling pups showed muscles with more restricted attachments, reduced muscle lines of action, and less diversity in the fiber orientation. The absence of the postorbital constriction also resulted in a distinct morphology of the m. temporalis pars profunda, through two bundles, one anterior and one posterior, which insert more inferiorly into the mandible. These major changes can be related to the onset of mastication and to size‐related changes in growing weaned age classes. In general, all adductor muscles grew with positive allometry, and increased their fixation areas through, in part, the development of specific regions of the cranium and mandible. Their lines of action also increase and diversify along ontogeny. These changes can be related to the functional requirements for fixation during lactation, which shift to adduction and mastication movements after weaning. [ABSTRACT FROM AUTHOR]

Simple Summary: Chlamydial infections are a major threat to the health of koalas (Phascolarctos cinereus), an iconic Australian marsupial. Among the different chlamydial species, Chlamydia pecorum (C. pecorum) is the major pathogen infecting koalas, affecting their health and long-term survival, both in the wild and in captivity. Therefore, a deeper understanding of chlamydial infections, including their epidemiology, transmission mode, pathogenesis, host immune response, control, and prevention, is critical for the management of chlamydial infections in koalas. Herein, we discuss the current literature on C. pecorum infection in koalas, including the epidemiology, transmission, pathogenesis, immune response, and control strategies for chlamydial infection, with the aim of improving koala health and achieving effective conservation strategies. Chlamydial infections pose a significant threat to koala populations. Chlamydia pecorum (C. pecorum) remains the major chlamydial species affecting koala health, both in the wild and in captivity, and chlamydial infections are considered important factors affecting the long-term survival of koalas. A clear understanding of chlamydial infections, including the epidemiology, transmission mode, pathogenesis, immune response, control, and prevention thereof, is essential for improving the management of chlamydial infections in koalas. In this study, we discuss the important advances made in our understanding of C. pecorum infection in koalas, focusing on the epidemiology of chlamydial infections, and the transmission, pathogenesis, immune response, and control strategies for chlamydial infection, with the aim of improving koala health and achieving effective conservation strategies. [ABSTRACT FROM AUTHOR]

Males of the endangered northern quoll (Dasyurus hallucatus) are facultatively semelparous, often dying following their first breeding season. This is often driven by high breeding costs: males travel and mate extensively in breeding season, resulting in reduced body condition. Annual post‐breeding survival rates for male northern quolls have been recorded between 0% and 12.5% across their range in northern Australia. We highlight an observed 50% survival rate of male northern quolls (3 of 6) living into their second year in a Pilbara mining landscape. High male survival here may be attributed to above average rainfall in the landscape and reduced breeding opportunities, due to low female abundance—likely driven by large amounts of unfavourable mining land. This likely led to lower hormonal stress associated with breeding for males, as well as increased resource availability. Given northern quoll population persistence is highly dependent on breeding success, high survival of male northern quolls may inadvertently stabilize populations if they can breed again in a second year, though this is yet to be observed in the Pilbara region. Nevertheless, semelparity of male northern quolls likely varies with environmental and demographic factors, demonstrating that northern quoll populations may be resilient to disturbance in an unpredictable semi‐arid environment. [ABSTRACT FROM AUTHOR]

Bat‐pollinated plants feature open flowers, facilitating easy access to their abundant nectar for various animal groups. The Caatinga, a Brazilian Seasonally Tropical Dry Forest, stands out globally as a hotspot for bat‐pollinated plants. This study presents the first documentation of the opossum Didelphis albiventris (Marsupialia) engaging in the consumption of nectar on flowers of Hymenaea cangaceira (Fabaceae), a bat‐pollinated tree species within the Caatinga. The observation spanned five nights and occurred unexpectedly during an experiment involving bagged flowers to assess nectar dynamics. Initially, torn bags were discovered containing flowers, which nectar had been consumed. Subsequent nights revealed the opossum actively exploring bagged flowers, likely guided by the fragrant nectar of H. cangaceira, and unmanipulated flowers located in the canopy's upper reaches. Given the opossum's contact with reproductive structures during these visits, it emerges as a potential pollinator. Following this observation, a comprehensive literature review on Didelphis interactions with other plants was conducted, leading to the construction of a meta network. This network unequivocally illustrates that the majority of plants visited by Didelphis indeed have bats as their primary pollinators. Owing to the nocturnal, arboreal and stealthy nature of opossums, documenting their interactions with flowers proves highly challenging. Consequently, our record highlights significant knowledge gaps in comprehending the interplay between opossums and chiropterophilous flowers. These gaps include the under‐sampling of this process in the Caatinga, the role of olfactory signalling and the broader consequences of this unique interaction. [ABSTRACT FROM AUTHOR]

The bushy-tailed opossum Glironia venusta is a rare marsupial from Amazonia, with most of the known records obtained through scant visualization/photography events or by few captures/deposit of specimens in scientific collections. This study presents unusual records for the species: the first record of individuals dead due to vehicle collision, and a specimen opportunistically trapped into a mistnet. The data presented herein provide additional morphometrical data and ecological insights about G. venusta. Although this species is considered essentially arboreal, our records indicate that movements on ground are part of its habits. [ABSTRACT FROM AUTHOR]

Trypanosoma evansi, the hemoflagellate pathogen that causes "surra," is a protozoan that infects the widest variety of mammals worldwide, primarily horses, camels, dogs, and wild animals. Cases of canine trypanosomiasis caused by T.evansi have been reported in the Brazilian pantonal region. This study determined the prevalence of T.evansi and investigate risk factors. The study used blood samples from dogs in the municipality of Barão de Melgaço in the pantonal of the state of Mato Grosso, Brazil. The owner was given a structured epidemiological questionnaire containing information about the risk factors. The quantitative polymerase chain reaction technique was used to detect T.evansi DNA using species-specific oligonucleotides TevF and TevR of the gene encoding a 227-bp portion of the glycoprotein of the variant surface (VSG) T.evansi Rode Trypanozoon (RoTat) 1.2. Two (prevalence of 0.5%) genetic materials of T.evansi were reported in the403 samples. Although, no risk factor was associated with infection (P > 0.05), proximity to vegetation and streams, as well as the presence of tabanids, rodents, and marsupials, which are factors in the occurrence of infection, were observed in positive dogs, implying that the municipality of Barão de Melgaço has epidemiological characteristics that allow canine infection by T.evansi. [ABSTRACT FROM AUTHOR]

Simple Summary: A transcriptome landscape of therian mammals is known, but it remains unclear how transcriptomic patterns have evolved in a marsupial- or eutherian-specific way. It is important to understand marsupial- or eutherian-specific transcriptomic patterns since their fitness and sex differentiation are different. This study examines therian testis transcriptomes to elucidate marsupial and eutherian uniqueness in male differentiation. Using the massive transcriptomic data, we show the evolutionary tempo and mode of testis-expressed genes in Theria and identify candidate genes involved in the specificity of marsupial or eutherian testes. Gene expression patterns differ in different tissues, and the expression pattern of genes in the mammalian testis is known to be extremely variable in different species. To clarify how the testis transcriptomic pattern has evolved in particular species, we examined the evolution of the adult testis transcriptome in Theria using 10 species: two marsupials (opossum and Tasmanian devil), six eutherian (placental) mammals (human, chimpanzee, bonobo, gorilla, rhesus macaque, and mouse), and two outgroup species (platypus and chicken). We show that 22 testis-expressed genes are marsupial-specific, suggesting their acquisition in the stem lineage of marsupials after the divergence from eutherians. Despite the time length of the eutherian stem lineage being similar to that of the marsupial lineage, acquisition of testis-expressed genes was not found in the stem lineage of eutherians; rather, their expression patterns differed by species, suggesting rapid gene evolution in the eutherian ancestors. Fifteen testis-expressed genes are therian-specific, and for three of these genes, the evolutionary tempo is markedly faster in eutherians than in marsupials. Our phylogenetic analysis of Rho GTPase-activating protein 28 (ARHGAP28) suggests the adaptive evolution of this gene in the eutherians, probably together with the expression pattern differentiation. [ABSTRACT FROM AUTHOR]

Interleukin-1α is a suggested dual-function cytokine that diverged from interleukin-1β in mammals potentially by acquiring additional biological roles that relate to highly conserved regions in the pro-domain of interleukin-1α, including a nuclear localisation sequence and histone acetyltransferase-binding domains. Why evolution modified pro-interleukin-1α's subcellular location and protein interactome, and how this shaped interleukin-1α's intracellular role, is unknown. Here we show that TurboID proximity labelling with pro-interleukin-1α suggests a nuclear role for pro-interleukin-1α that involves interaction with histone acetyltransferases, including EP300. We also identify and validate inactivating mutations in the pro-interleukin-1α nuclear localisation sequence of multiple mammalian species, including toothed whales, castorimorpha and marsupials. However, histone acetyltransferase-binding domains are conserved in those species that have lost pro-interleukin-1α nuclear localisation. Together, these data suggest that histone acetyltransferase binding and nuclear localisation occurred together, and that while some species lost the nuclear localisation sequence in their pro-interleukin-1α, histone acetyltransferase binding ability was maintained. The nuclear localisation sequence was lost from several distinct species at different evolutionary times, suggesting convergent evolution, and that the loss of the nuclear localisation sequence confers some important biological outcome. Interleukin (IL)-1α is a critical inflammatory cytokine and yet its intracellular role is poorly understood. Here, the authors use proximity labelling of pro-IL-1α and assess its interactome, and dissect the presence and impact on a conserved nuclear interaction and its impact on the immunobiology and evolutionary convergence/divergence between species. [ABSTRACT FROM AUTHOR]

Didelphid marsupials are considered a morphologically unspecialized group with a generalist diet that includes vertebrates, invertebrates, and plant matter. While cranium and scapula variation has already been examined within Didelphidae, variation in mandible shape, usually associated with diet or phylogeny in other mammalian groups, has not yet been properly assessed in the family. We evaluated the variation in mandible shape and size of didelphids (2470 specimens belonging to 94 species) using 2D geometric morphometrics. We classified the diet of the didelphids into four broad categories to assess whether morphospace ordination relates to dietary habits. We also provided the most comprehensive phylogeny for the family (123 out of the 126 living species) using 10 nuclear and mitochondrial genes. We then mapped mandible size and shape onto that phylogeny for 93 selected taxa and ancestral size and shapes were reconstructed by parsimony. We found phylogenetically structured variation in mandible morphology between didelphid groups, and our results indicate that they have a significant phylogenetic signal. The main axis of shape variation is poorly related to size, but the second is strongly allometric, indicating that allometry is not the main factor in shaping morphological diversity on their mandibles. Our results indicate that the shape and size of the ancestral mandible of didelphids would be similar to that of the current species of the genus Marmosa. [ABSTRACT FROM AUTHOR]

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions. We tested hypotheses on the relationships between individuals' positions within networks (specialization and centrality) of 4 populations of the mouse opossum Gracilinanus agilis and their traits (i.e. body length, body condition, tail length relative to body length, sex, reproductive condition, and botfly parasitism) and also seasonal effects in the Brazilian savanna. Individuals with lower body length, better body condition, and relatively shorter tail were more specialized (i.e. less connected within the network). Individuals were also more specialized and less connected during the warm-wet season. The relationship between individuals' position in the network and body traits, however, was independent of season. We propose that specialization may arise not only as a result of preferred feeding strategies by more capable individuals (i.e. those with better body condition and potentially prone to defend and access high-quality food resources) but also because of morphological constraints. Smaller/younger individuals (consequently with less experience in foraging) and short-tailed individuals (less skilled to explore the vertical strata of the vegetation) would feed only on a subset of the available food resources and consequently become more specialized. Moreover, individuals are more specialized during the warm-wet season because of high competition (population-dense period) and higher ecological opportunities (resource-rich period). Therefore, our study reveals the relevance of individual traits in shaping interaction patterns and specialization in populations. [ABSTRACT FROM AUTHOR]

The distribution pattern of a taxon is a consequence of historical and contemporary processes—specifically ecological and evolutionary processes—which tend to result in distributional congruence among species that respond similarly to the same processes. This congruence leads to the establishment of areas of endemism that are important for delimiting biogeographic regions. In the Neotropical region, different definitions of area of endemism have been proposed based on the distributional patterns of mammal species, each according to different methods and assumptions. In this study, we aimed to identify areas of endemism of Neotropical mammals, represented by 361 species of Placentalia (Xenarthra, Chiroptera, and Carnivora) and Marsupialia (Didelphimorphia and Paucituberculata), using an endemicity analysis implemented by the software NDM (eNDeMism software) and a hierarchical cluster analysis based on Simpson's beta dissimilarity metric (βsim). The results suggest alternative spatial configurations within northern and southern parts of the Neotropics along transition zones. Additionally, there are indications of more restricted areas of endemism throughout the Neotropical region and with more species supporting the areas, such 1 area located in the region corresponding to the Atlantic forest and 2 areas corresponding to Mexican transition zone. The study enhances our understanding of Neotropical mammal biogeography and underscores the importance of using primary distribution data. Previous studies found 82 endemic species based on range maps, whereas our analyses identified 172 endemic species, including 125 that are newly proposed as such, and also confirmed the existence of 47 previously reported endemic species. [ABSTRACT FROM AUTHOR]

The genus Caenolestes is the most species-rich of the marsupial order Paucituberculata. Two species inhabit Colombia (and also occur in Ecuador) with a discontinuous distribution that has not been accounted for in previous studies— Caenolestes fuliginosus known from the Central and Eastern Andes, and C. convelatus restricted to the Western Andes. Here, we present new and noteworthy records of Caenolestes from the Western Andes at the distributional gap of C. convelatus , and outside the known range of C. fuliginosus. We present detailed comparisons using discrete and continuous diagnostic morphological characters, with type material and additional specimens collected nearby, to assess the identity of the new specimens. We performed statistical analyses at species and subspecies levels, and used a principal components analysis to explore the ordination of the new specimens in morphological space. We found that although these specimens are from the Western Andes, they present traits similar to C. fuliginosus and show great overlap with the morphospace of that species. The new records did not differ statistically with C. fuliginosus or any of its subspecies, but they differed in 20 craniodental measurements from C. convelatus. We also report differences at subspecies level within and between species. Based on these observations, we identified these records as C. fuliginosus , expanding its known distribution to the midportion of the Western Andes, across de Cauca valley. We discuss the biogeography of these 2 species in light of the new data and the context of high Andean habitats, especially regarding the contrasting biogeographical patterns found in other taxa in the Northern Andes. Finally, we discuss the need for a new and exhaustive review of the systematics and biogeography of the genus. [ABSTRACT FROM AUTHOR]

Background: Marsupials and rodents are the most important wild and synanthropic hosts of Trypanosoma cruzi due to the high frequency of infection, maintenance of diverse genetic populations of the parasite, and their close proximity to interact with both transmission cycles, sylvatic and peridomestic. Our aim was to identify the discrete typing units (DTU) of T. cruzi from different wild and synanthropic hosts in two regions of Mexico and to carry out a review of historical data focusing on current knowledge on the diversity and T. cruzi DTUs of host species. Materials and Methods: One hundred fifteen samples were obtained from two areas in Tabasco and Nayarit state. The presence of T. cruzi was evaluated by PCR. Results: The 12.6% (12/95) of samples from Tabasco and 65% (13/20) from Nayarit were found to be positive for parasite DNA. All the sequences analyzed were grouped in T. cruzi DTU I; low nucleotide diversity was observed in Tabasco (π = 0.00566, and ϴ = 0.00632), while high genetic diversity was observed in Nayarit sequences, up to 8.63 (π) to 11.10 (ϴ) times greater than Tabasco sequences. Genetic flow and migration between Tabasco, and Nayarit were scarce (FST = 0.37329 and Nm = 0.42), and genetic exchange was observed only between nearby areas. The bibliographic review of hosts in Mexico, together with our data, shows a heterogeneous T. cruzi prevalence in Chiroptera and domestic animals. For Atelidae and Canids, prevalence is generally below 25%. However, a high prevalence, greater than 25% and up to 100%, was recorded in Didelphimorphia, and Rodentia. Few studies in regions of Mexico have been described as infected with the parasite; in these, the genetic group with the highest prevalence is the DTU I. Conclusion: Marsupials and rodents are important reservoirs of T. cruzi; DTU I was frequently reported; however, recent genetic and reservoir studies have demonstrated the presence of greater diversity of genetic groups. [ABSTRACT FROM AUTHOR]

Understanding how animals respond to fire is crucial for conservation efforts in fire‐prone regions across the world. How fire affects animal movement is of particular interest, as it determines access to resources, exposure to risks, and connectivity of populations. We report on observations of the movement patterns and habitat selection of two northern quolls (Dasyurus hallucatus, an endangered marsupial predator), one male and one female, in the Pilbara region of Western Australia. We employed GPS tracking and integrated step selection functions to analyse habitat preferences in relation to fire, and used accelerometry data to assess the energetic costs of using burnt areas. The male northern quoll avoided recently burnt areas, likely due to increased energetic demands and predation risks during the breeding season. In contrast, the female northern quoll neither avoided nor preferred burnt areas, but showed a preference for rocky areas. The female appeared to move through burnt areas to access suitable breeding habitat. The movement patterns observed in the two individuals might reflect a broader pattern of sex‐specific responses to fire, but further research is required to confirm how general the pattern is. Our observations indicate that fire can influence northern quoll movement, with female dependence on rocky areas increasing use of suboptimal habitats, and male avoidance of burnt areas raising potential implications for breeding dispersal and population dynamics. Given the expected increases in fire size and frequency, further research on northern quoll responses to fire in the Pilbara is needed to determine if the pattern we observed is consistent across the broader population. [ABSTRACT FROM AUTHOR]

Retroviruses are an ancient viral family that have globally coevolved with vertebrates and impacted their evolution. In Australia, a continent that has been geographically isolated for millions of years, little is known about retroviruses in wildlife, despite the devastating impacts of a retrovirus on endangered koala populations. We therefore sought to identify and characterize Australian retroviruses through reconstruction of endogenous retroviruses from marsupial genomes, in particular the Tasmanian devil due to its high cancer incidence. We screened 19 marsupial genomes and identified over 80,000 endogenous retrovirus fragments which we classified into eight retrovirus clades. The retroviruses were similar to either Betaretrovirus (5/8) or Gammaretrovirus (3/8) retroviruses, but formed distinct phylogenetic clades compared to extant retroviruses. One of the clades (MEBrv 3) lost an envelope but retained retrotranspositional activity, subsequently amplifying throughout all Dasyuridae genomes. Overall, we provide insights into Australian retrovirus evolution and identify a highly active endogenous retrovirus within Dasyuridae genomes. [ABSTRACT FROM AUTHOR]

The Eastern Quoll Dasyurus viverrinus was an abundant, widespread and visible marsupial in the late 19th and early 20th Centuries, well known as a 'native cat' to people living in regional south-eastern Australia. In searches of newspapers on the Trove database, we found numerous historical reports in which horses were described as having 'native cat back' or similar descriptions. Most reports were from Victoria, with fewer from New South Wales, South Australia and Western Australia. The first report was from 1830 (Sydney, NSW) and the last in 1947 (Preston, Vic.), with most between 1860 and 1910. These reports provide a fascinating example of how familiarity with a widespread, abundant native species led to appropriation of its appearance for use in daily life. The decline and cessation of such descriptive terms for horses (1930s-1940s) followed the dramatic decline of the Eastern Quoll on mainland Australia in the early 20th century. [ABSTRACT FROM AUTHOR]

Wildlife harbour a diverse range of microorganisms that affect their health and development. Marsupials are born immunologically naïve and physiologically underdeveloped, with primary development occurring inside a pouch. Secretion of immunological compounds and antimicrobial peptides in the epithelial lining of the female's pouch, pouch young skin, and through the milk, are thought to boost the neonate's immune system and potentially alter the pouch skin microbiome. Here, using 16S rRNA amplicon sequencing, we characterised the Tasmanian devil pouch skin microbiome from 25 lactating and 30 non-lactating wild females to describe and compare across these reproductive stages. We found that the lactating pouch skin microbiome had significantly lower amplicon sequence variant richness and diversity than non-lactating pouches, however there was no overall dissimilarity in community structure between lactating and non-lactating pouches. The top five phyla were found to be consistent between both reproductive stages, with over 85% of the microbiome being comprised of Firmicutes, Proteobacteria, Fusobacteriota, Actinobacteriota, and Bacteroidota. The most abundant taxa remained consistent across all taxonomic ranks between lactating and non-lactating pouch types. This suggests that any potential immunological compounds or antimicrobial peptide secretions did not significantly influence the main community members. Of the more than 16,000 total identified amplicon sequence variants, 25 were recognised as differentially abundant between lactating and non-lactating pouches. It is proposed that the secretion of antimicrobial peptides in the pouch act to modulate these microbial communities. This study identifies candidate bacterial clades on which to test the activity of Tasmanian devil antimicrobial peptides and their role in pouch young protection, which in turn may lead to future therapeutic development for human diseases. [ABSTRACT FROM AUTHOR]

The Andean white ear opossum (Didelphis pernigra, Allen 1900) is one of the three species of the genus Didelphis reported in Colombia. Here we present a systematic review of D. pernigra in Colombia, with a geographical and altitudinal distribution hypothesis from the country. We reported geographic records and scientific available information of D. pernigra in 40 studies, 55.26 % of the available literature corresponded to local and regional inventories; 23.68 % of other documents were studies about mammal assemblages, while 21.05 % were specific studies about the species and the genus Didelphis in Colombia. We classified literature according to the following subcategories: natural history, diet, inventories, threats, reproduction, uses and perceptions. Most of the literature corresponded to detection in inventories (55.26 %), followed by natural history information (21.05 %) and threats (7.89 %). Research about diet, uses, perception and reproduction, had the lowest proportion with 5.26 %. Regarding distribution, geographic records ranged between 1060 and 3740 m across the three Andean ranges of Colombia. In general, little is known about the ecology or natural history of the species, efforts should be focused on filling the information gaps about natural history, and surveys should fill the distribution gaps along the Western and Central ranges of Colombia. [ABSTRACT FROM AUTHOR]

Landscape productivity and resource dispersion are key drivers of the movement patterns of many species. In less productive environments, home ranges are generally larger as individuals travel further to access resources. The greater bilby (Macrotis lagotis) has been reintroduced to several feral predator exclosures to reduce their extinction risk. Understanding how landscape productivity and resource dispersion influence bilby space use is critical to enable effective management of populations in exclosures. At two exclosures, we tested three hypotheses: 1. Bilbies would preferentially utilize habitats with sandy substrates (<20% clay content), as they are suitable for digging burrows and foraging pits; 2. Home ranges would be larger at the arid site compared to the semi‐arid site due to lower productivity and patchier distribution of preferred habitats; and 3. Bilbies would travel further each night at the arid site to access preferred habitats. Rainfall was used as an indicator of productivity, and dispersion of preferred habitats as an indicator of resource dispersion. The study was undertaken during average rainfall conditions and under similar bilby population densities at both sites. GPS loggers recorded home ranges and movements of 10 bilbies at the arid site, and 11 bilbies at the semi‐arid site. Seventeen of the 21 bilbies preferentially utilized habitats with sandy substrates, which were less abundant at the arid site. There were no significant differences in home range size or nightly movements between the sites for either sex. We suggest the average rainfall conditions at both sites, and the dietary flexibility of bilbies, supported the maintenance of relatively small and stable home ranges (particularly for females). The effects of landscape productivity and resource dispersion on bilby space use are more likely to be evident during extended periods of below average rainfall. Bilby home range studies during low rainfall conditions (e.g. drought) are required for the effective, long‐term management of exclosure populations. [ABSTRACT FROM AUTHOR]

A 7-y-old, castrated male, leucistic sugar glider (Petaurus breviceps) was presented because of a progressive history of lethargy, ataxia, diarrhea, and anorexia. Abdominal ultrasound revealed fluid in the abdomen and an infiltrative mass in the liver. Due to a poor prognosis, euthanasia was performed. Postmortem examination revealed a focally extensive, infiltrative, off-white, firm mass in the liver with adhesion to the omentum, mesentery, gastric serosa, and diaphragm. The remaining hepatic parenchyma was diffusely yellow. Histologically, the hepatic mass was consistent with metastatic cholangiocarcinoma (cholangiocellular carcinoma) with proliferation of neoplastic epithelial cells surrounded by marked desmoplasia. Neoplastic cells expanded and infiltrated the adjacent omentum, mesentery, and the serosal surfaces of the stomach, kidney, and small and large intestines. To our knowledge, cholangiocarcinoma has not been reported previously in a sugar glider. [ABSTRACT FROM AUTHOR]

Man’s natural inclination to classify and hierarchize the living world has prompted neurophysiologists to explore possible differences in brain organisation between mammals, with the aim of understanding the diversity of their behavioural repertoires. But what really distinguishes the human brain from that of a platypus, an opossum or a rodent? In this review, we compare the structural and electrical properties of neocortical neurons in the main mammalian radiations and examine their impact on the functioning of the networks they form. We discuss variations in overall brain size, number of neurons, length of their dendritic trees and density of spines, acknowledging their increase in humans as in most large-brained species. Our comparative analysis also highlights a remarkable consistency, particularly pronounced in marsupial and placental mammals, in the cell typology, intrinsic and synaptic electrical properties of pyramidal neuron subtypes, and in their organisation into functional circuits. These shared cellular and network characteristics contribute to the emergence of strikingly similar large-scale physiological and pathological brain dynamics across a wide range of species. These findings support the existence of a core set of neural principles and processes conserved throughout mammalian evolution, from which a number of species-specific adaptations appear, likely allowing distinct functional needs to be met in a variety of environmental contexts. [ABSTRACT FROM AUTHOR]

The Paucituberculata are a group of marsupials endemic to South America, recorded from the Early Eocene to the present. In terms of taxonomy and qualitative morphology, paucituberculatans are a quite diverse and disparate group, especially considering their extinct representatives. This study aimed to investigate the variability in the quantitative morphology of paucituberculatans in the context of the largest morphometric study of the group performed to date. Due to the fragmentary fossil record, this work focused on lower dental morphology which allowed us to compare around 95% of paucituberculatan species through the measurement and analysis of almost 1500 specimens. Dental measurements of 27 variables were analysed by Principal Component Analysis and Partial Least Squares correlation as exploratory methods. As a result, it is shown that the continuous variability is expressed not only in size differences among species but also in morphological variability of individual teeth, and differences in size and proportions along the molar row. We conclude that paucituberculatans are a group of important morphological diversity regarding quantitative morphology. Many of the quantitative taxonomic features discussed in the literature were corroborated in this study. In addition, we discussed potential evolutionary and palaeoecological implications of this study, highlighting prospects for future studies. [ABSTRACT FROM AUTHOR]

Brazil has earned the moniker "arbovirus hotspot", providing an ideal breeding ground for a multitude of arboviruses thriving in various zoonotic and urban cycles. As the planet warms and vectors expand their habitat range, a nuanced understanding of lesser-known arboviruses and the factors that could drive their emergence becomes imperative. Among these viruses is the Iguape virus (IGUV), a member of the Orthoflavivirus aroaense species, which was first isolated in 1979 from a sentinel mouse in the municipality of Iguape, within the Vale do Ribeira region of São Paulo State. While evidence suggests that IGUV circulates among birds, wild rodents, marsupials, bats, and domestic birds, there is no information available on its pathogenesis in both humans and animals. The existing literature on IGUV spans decades, is outdated, and is often challenging to access. In this review, we have curated information from the known literature, clarifying its elusive nature and investigating the factors that may influence its emergence. As an orthoflavivirus, IGUV poses a potential threat, which demands our attention and vigilance, considering the serious outbreaks that the Zika virus, another neglected orthoflavivirus, has unleashed in the recent past. [ABSTRACT FROM AUTHOR]

The studies of the small mammal fossil and recent assemblages from the Limay river basin (Northwestern Patagonia) have strongly increased during the last decade. Taxonomic, taphonomic, and paleoecological information about small rodents and marsupials recovered from fossil sites offers the opportunity to discuss the periods of change and stability in the conformation of their communities through the Anthropocene. Here, we used two large data matrix of fossil and recent small mammal samples. As starting point, we considered the small mammal record of Epullán Grande cave (LL thereafter), which covers the Early Holocene/Post-hispanic Period, in order to assess the impact of anthropic activities on the small mammal communities during the Anthropocene. The taphonomic analysis performed on the newest samples from LL confirms the predatory activity of Tyto furcata on sigmodontines and human consumption on caviomorphs (mostly for the last ca. 1000 years). The analysis of manganese oxide staining suggested higher levels of moisture during the earliest formation of the LL sequence. The taxonomic results indicate a major diversity in the small mammal fossil assemblages to the later periods of LL and other fossil sequences of the Limay basin of the Anthropocene. Conversely, opportunistic sigmodontines (Abrothrix olivacea, Calomys musculinus, Eligmodontia spp. and Oligoryzomys longicaudatus) experienced a growth in the recent samples. Some stenoic and specialist species (Euneomys spp., Lestodelphys halli, Loxodontomys micropus and Reithrodon auritus) were abundant in the temporal units associated with the Anthropocene, but now are in retraction. Additionally, the drop in the diversity of recent assemblages supports a restructuration of small mammal communities from Limay river basin occurred in the 20th century. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: In northern Australia, large native herbivorous mammals (weighing over 1000 kg) disappeared about 46 kya, and they have been replaced in the last 200 years by a range of introduced mammalian herbivores up to 1000 kg in bodyweight. Only one native herbivore has an adult bodyweight approaching 100 kg, and for the past 200 years, the total biomass of introduced domestic and wild vertebrate herbivores has massively exceeded that of native herbivorous species. Following a comprehensive review, we conclude that the current guild of native and introduced mammalian herbivores differentially utilises the landscape ecologically. However, climate- and anthropogenically related changes due to fire, drought, flooding, predation and introduced weeds are likely to have significant impacts on the trajectory of their relative ecological roles and populations. Given their differing ecological and dietary characteristics, against this backdrop, it is unclear what the potential impact of the dispersal of deer species could have in northern Australia. There is a dearth of supporting evidence to inform appropriate sustainable management should deer range expansion occur. We identify suitable research required to fill the identified knowledge gaps. We explored the ecological and historical factors that led to formation of the unique guild of native and introduced mammalian herbivores between 5 and 1000 kg in northern Australia. Following the disappearance of large native herbivores about 46 kya, and until the arrival of Europeans and their livestock, the only herbivorous mammals were mid-sized endemic marsupial macropods, which continued to utilise the same vegetation as their much larger former neighbours. Only one species of contemporary native herbivore has an adult bodyweight approaching 100 kg, and for the past 150–200 years, the total biomass of introduced domestic and wild vertebrate herbivores has massively exceeded that of native herbivorous species. We conclude that the current guild of native and introduced mammalian herbivores differentially utilises the landscape ecologically. However, climate- and anthropogenically related changes due to fire, drought, flooding, predation and introduced weeds are likely to have significant impacts on the trajectory of their relative ecological roles and populations. Given their differing ecological and dietary characteristics, against this backdrop, it is unclear what the potential impact of the dispersal of deer species could have in northern Australia. We hence focus on whether sufficient knowledge exists against which the potential impacts of the range expansion of three deer species can be adequately assessed and have found a dearth of supporting evidence to inform appropriate sustainable management. We identify suitable research required to fill the identified knowledge gaps. [ABSTRACT FROM AUTHOR]

While resource selection varies according to the scale and context of study, gathering data representative of multiple scales and contexts can be challenging especially when a species is small, elusive and threatened. We explored resource selection in a small, nocturnal, threatened species, the greater bilby, Macrotis lagotis , to test (1) which resources best predict bilby occupancy, and (2) whether responses are sex specific and/or vary over time. We tracked 20 bilbies and examined within home range resource selection over multiple seasons in a large (110 ha) fenced sanctuary in temperate Australia. We tested a set of plausible models for bilby resource selection, and found that food biomass (terrestrial and subterranean invertebrates and subterranean plants) and soil textures (% sand, clay and silt) best predicted bilby resource selection for all sampling periods. Selection was also sex specific: female resource use, relative to males, was more closely linked to the location of high-quality resources (invertebrate biomass). Bilby selection for roads was independent of season but varied over time with males selecting for areas closer to roads when plants increased in density off roads. Our findings demonstrate the importance of considering resource selection over multiple contexts and highlight a method to collect such data on a difficult to study, threatened species. Collecting such data is critical to understanding the habitat required by species. • We studied multiyear habitat selection by a small nocturnal marsupial. • Resource selection was sex specific and varied over time. • Females were more selective of high-quality resources. • A snapshot habitat selection study is often inadequate for conserving species. • Reintroductions can fill key knowledge gaps for data-deficient threatened species. [ABSTRACT FROM AUTHOR]

With the advancement of globalization, the spread of non-domesticated animal species which are becoming increasingly popular human companions, is observed. One of the species gaining popularity is the sugar glider, Petaurus breviceps. It is a small, omnivorous, arboreal, and nocturnal gliding possum. Many of the health problems recognized in sugar gliders kept in artificial conditions, stem from their specific anatomy, physiology, and behavior. Among the most commonly diagnosed health issues in sugar gliders are those associated with nutrition and stress, with neoplastic diseases, respiratory disorders including dyspnea, dental problems, inflammatory bowel disease, constipation and also diarrhea of various origin, lower urinary tract diseases, then mastitis and pouch infections, eye injuries, cataracts and moreover toxoplasmosis. This article provides a comprehensive review of these and other prevalent health disorders recognized in sugar gliders, supported by significant literature references. [ABSTRACT FROM AUTHOR]

Abstract The two species of the microbiotheriid marsupial genus Dromiciops (Dromiciops bozinovici: “Panchos's monito del monte” and Dromiciops gliroides: “monito del monte”) exhibit a marked latitudinal genetic differentiation. Nevertheless, it is unclear whether this differentiation results from neutral processes or can be explained, to some extent, by local adaptation to different environmental conditions. Here, we used an SNP panel gathered by Rad‐seq and searched for footprints of local adaptation (putative loci under selection) by exploring genetic associations with environmental variables in the two species of Dromiciops in Chilean and Argentinean populations. We applied three methods for detecting outlier SNPs and two genotype–environment associations approaches to quantify associations between allelic frequencies and environmental variables. Both species display strong genetic structure. D. bozinovici exhibited three distinct genetic groups, marking the first report of such structuring in this species using SNPs. In contrast, D. gliroides displayed four genetic clusters, consistent with previous studies. Both species exhibited an association of their genetic structure with environmental variables. D. bozinovici exhibited significant associations of allelic frequencies with elevation, precipitation during the warmest periods, and seasonality in the thermal regime. For D. gliroides, genetic variation appeared to be associated with more variables than D. bozinovici, including precipitation and temperature‐related variables, isothermality, and elevation. All the outlier SNPs were mapped to the D. gliroides reference genome to explore if they fell within functionally known genes. These results represent a necessary first step toward identifying the genome regions that harbor genes associated with climate adaptations in Dromiciops. Notably, we identified genes involved in various functions, including carbohydrate synthesis (ALG8), muscle and neuronal regulation (MEF2D), and stress responses (PTGES3). Ultimately, this study contributes valuable insights that can inform targeted conservation strategies aimed at preserving the genetic diversity of Dromiciops in the face of environmental challenges.

An adult female black-eared opossum (Didelphis aurita) was found in the city of Guarulhos, Brazil, and was sent to veterinary care for clinical examination and future rehabilitation. In the physical exam, it was possible to verify mobility between the hemimandibles. The animal was submitted to the anesthetic procedure for a complete oral exam, intraoral radiography, and possible surgical intervention. The opossum was diagnosed with mandibular symphysis disjunction, needing surgery. The technique chosen was the labial locking system with buttons and cerclages. After the procedure, the animal was sent to the environmental organs for rehabilitation. After 40 days, the locking system was removed showing a complete healing of the mandibular symphysis. The animal was reintroduced to nature within 45 days of the procedure.

Abstract We record and analyze the movement patterns of the marsupial Didelphis aurita at different temporal scales. Animals trajectories are collected at a daily scale by using spool-and-line techniques and, with the help of radio-tracking devices, animals traveled distances are estimated at intervals of weeks. Small-scale movements are well described by truncated Lévy flight, while large-scale movements produce a distribution of distances which is compatible with a Brownian motion. A model of the movement behavior of these animals, based on a truncated Lévy flight calibrated on the small scale data, converges towards a Brownian behavior after a short time interval of the order of 1 week. These results show that whether Lévy flight or Brownian motion behaviors apply, will depend on the scale of aggregation of the animals paths. In this specific case, as the effect of the rude truncation present in the daily data generates a fast convergence towards Brownian behaviors, Lévy flights become of scarce interest for describing the local dispersion properties of these animals, which result well approximated by a normal diffusion process and not a fast, anomalous one. Interestingly, we are able to describe two movement phases as the consequence of a statistical effect generated by aggregation, without the necessity of introducing ecological constraints or mechanisms operating at different spatio-temporal scales. This result is of general interest, as it can be a key element for describing movement phenomenology at distinct spatio-temporal scales across different taxa and in a variety of systems.

Recent experiments have demonstrated that carnivores and ungulates in Africa, Asia, Europe and North America fear the human 'super predator' far more than other predators. Australian mammals have been a focus of research on predator naiveté because it is suspected they show atypical antipredator responses. To experimentally test if mammals in Australia also most fear humans, we quantified the responses of four native marsupials (eastern grey kangaroo, Bennett's wallaby, Tasmanian pademelon, common brushtail possum) and introduced fallow deer to playbacks of predator (human, dog, Tasmanian devil, wolf) or non-predator control (sheep) vocalizations. Native marsupials most feared the human 'super predator', fleeing humans 2.4 times more often than the next most frightening predator (dogs), and being most, and significantly, vigilant to humans. These results demonstrate that native marsupials are not naïve to the peril humans pose, substantially expanding the taxonomic and geographic scope of the growing experimental evidence that wildlife worldwide generally perceive humans as the planet's most frightening predator. Introduced fallow deer fled humans, but not more than other predators, which we suggest may result from their being introduced. Our results point to both challenges concerning marsupial conservation and opportunities for exploiting fear of humans as a wildlife management tool. [ABSTRACT FROM AUTHOR]

The eastern quoll (Dasyurus viverrinus) is an endangered marsupial native to Australia. Since the extirpation of its mainland populations in the 20th century, wild eastern quolls have been restricted to two islands at the southern end of their historical range. Eastern quolls are the subject of captive breeding programs and attempts have been made to re-establish a population in mainland Australia. However, few resources currently exist to guide the genetic management of this species. Here, we generated a reference genome for the eastern quoll with gene annotations supported by multi-tissue transcriptomes. Our assembly is among the most complete marsupial genomes currently available. Using this assembly, we infer the species' demographic history, identifying potential evidence of a long-term decline beginning in the late Pleistocene. Finally, we identify a deletion at the ASIP locus that likely underpins pelage color differences between the eastern quoll and the closely related Tasmanian devil (Sarcophilus harrisii). Genome sequencing of the eastern quoll, an endangered marsupial, describes historical population declines and identifies the likely basis of its colour differences with the closely related Tasmanian devil. [ABSTRACT FROM AUTHOR]

In this contribution, we investigate two sparassodonts from the Sarmiento Formation (Colhuehuapian Age; Early Miocene) recovered at the Patagonian locality of Sacanana, Chubut Province, Argentina. The first specimen (MACN-Pv CH1911), identified as Sipalocyon externus, is an almost complete cranium with upper dentition. The second specimen (MACN-Pv CH40), referred to Borhyaena macrodonta, consists of a fragmentary rostral portion of the face with associated m3–m4. The cranium of S. externus was studied through µCT-scanning to investigate its internal anatomy and infer paleoecological aspects of olfaction and hearing. In general, the endocranial anatomy and encephalization quotient are like those of other metatherians. We report the presence of an accessory transverse diploic sinus that has not previously been described in marsupials. Elements of the nasal cavity (e.g., turbinals, ossified nasal septum, cribriform plate) of S. externus exhibit features that are widespread among marsupials. Sense of olfaction, as evaluated from the cribriform plate and the 3D models of the olfactory bulbs, appears to have grossly resembled that of the domestic cat, a well-researched therian proxy. The dimensions of the tympanic membrane, as estimated from the preserved ectotympanic, suggest that the optimal hearing frequency of S. externus would have been similar to that of extant carnivorous marsupials. In sum, our study suggests that S. externus was a typical small-bodied (2–3 kg) hypercarnivorous metatherian that primarily relied on vision to hunt its prey, complemented by other sensory capabilities (olfaction and hearing), in a similar manner to small felids. [ABSTRACT FROM AUTHOR]

During periods of torpor, hibernators can reduce metabolic rate (MR) and body temperature (T b) substantially. However, to avoid physiological dysfunction at low temperatures, they defend T b at a critical minimum, often between ~0°C and 10°C via an increase in MR. Because thermoregulation during torpor requires extra energy, individuals with lower T b's and thus minimal MR during torpor should be selected in colder climates. Such inter- and intraspecific variations occur in some placental mammals, but for the evolutionary separate marsupials, available information is scarce. Marsupial eastern pygmy possums (Cercartetus nanus ; ~22 g body mass), widely distributed along the Australian southeastern coast including subtropical to alpine areas, were used to test the hypothesis that the defended T b of torpid individuals is related to the climate of their habitat. Possums were captured from five regions, 1,515 km apart, with midwinter (July) minimum environmental temperatures (min T env's) ranging from −3.9°C to 6.6°C. Captive possums in deep torpor were slowly cooled with ambient temperature (T a), while their MR was measured to determine the minimum torpor metabolic rate (TMR), the T a at which their MR increased for thermoregulation (min T a), and the corresponding minimum T b (min T b). Partial least squares regression analysis revealed that T a and T env were the strongest explanatory variables for the min T b. The min T b and T a were also correlated with latitude but not elevation of the capture sites. However, the best correlations were observed between the min T env and the min T b and T a for individuals experiencing min T env > 0 ° C ; these individuals thermoconformed to min T a's between −0.8°C and 3.7°C, and their min T b ranged from 0.5°C to 6.0°C and was 0.5°C–2.6°C below the min T env at the capture site. In contrast, individuals experiencing a min T env of −3.9°C regulated T b at 0.6 ° C ± 0.2 ° C or 4.5°C above the T env. The minimum TMR of all possums did not differ with T a and thus did not differ among populations and was 2.6% of the basal MR. These data provide new evidence that thermal variables of marsupials are subject to regional intraspecific variation. It suggests that min T b is a function of the min T env but only above 0°C, perhaps because the T b − T a differential for torpid possums in the wild, at a min T env of −3.9°C, remains small enough to be compensated by a small increase in MR and does not require the physiological capability for a reduction of T b below 0°C. [ABSTRACT FROM AUTHOR]

Introduced predators have been implicated in the extinction or range reduction of many Australian species, potentially due to native wildlife exhibiting prey naivety. We used traps with predator faeces present, monitored by camera traps, to determine if Australian mammals responded to native and introduced predator faeces. The presence of either faeces did not influence the trap or camera captures of any species. Some Australian mammals may exhibit prey naivety and not react to introduced predators. Using camera traps, we assessed how native mammals reacted to predator faeces placed in front of the traps. Presence of predator faeces did not influence trap or camera captures. Photograph by Meg Edwards. [ABSTRACT FROM AUTHOR]

The carnivorous marsupial genus Antechinus is well known for exhibiting semelparity – every year, all males die after the 1–3 week breeding period. Death of males potentially presents an opportunity for cheap energy gain via cannibalism for still-living male and female antechinuses. Cannibalistic behaviour has been reported in some dasyurids, but direct observations in the wild are rare. Here, we document observations of a mainland dusky antechinus (Antechinus mimetes mimetes) eating a recently deceased conspecific during the breeding period at Point Lookout, New England National Park, New South Wales. This provides rare field-based evidence of opportunistic cannibalism in a semelparous mammal. The carnivorous marsupial genus Antechinus is well known for exhibiting suicidal reproduction – every year, all males die after the 1–3 week breeding period. The death of males presents an opportunity for cheap energy gain via cannibalism for still-living male and female antechinuses. Here, we report cannibalism in the mainland dusky antechinus (Antechinus mimetes mimetes) – an individual was observed eating a dead member of its own species during the breeding period. This is rare field-based evidence of opportunistic cannibalism in a mammal. [ABSTRACT FROM AUTHOR]

Camera trap model and setup choice can significantly affect data collection. This study investigated standard-angle Reconyx and wide-angle Swift camera traps in different setups and how the choice of equipment influenced detection and individual identification of the chuditch (Dasyurus geoffroii). Camera models were placed side-by-side in four setups: (i) single and (ii) paired camera traps 30 cm above ground; and single cameras (iii) 1 m and (iv) 2 m above ground, with a lure (tuna oil) in the centre of all setups. Swifts had a higher Detection probability than Reconyx, although the number of detections with identified individuals did not significantly differ between camera models. The 30 cm paired camera setups had the highest Detection and Identification probabilities for both camera models, with both probabilities decreasing as cameras were positioned higher. Camera model and setup choice are important in obtaining detection and identification data, and should be considered when planning studies and interpreting results. Many wildlife studies using camera traps require a high probability of animal detection and, depending on study aim, the ability to identify individuals. For a cryptic species this can be difficult, but testing different setups for camera traps improves both detection and individual identification. In the case of the chuditch, a medium-sized marsupial carnivore, paired cameras at 30 cm height had the best Detection and Identification probability. This setup can be used in a variety of chuditch studies to gather more useable data and would increase the reliability of results such as population density estimates. Photograph by Melissa Taylor. [ABSTRACT FROM AUTHOR]

There are no detailed descriptions of deaths in species of marsupials in the scientific literature, nor of their responses to dead conspecifics. A camera trap captured the death of a southern hairy-nosed wombat (Lasiorhinus latifrons) and the responses of other wombats to its body. The emaciated wombat lay down and died over 2–3 h near a burrow. In the following months, its body was inspected 22 times by at least four wombats. It is unclear whether the wombats purposefully visited the dead wombat. Inspecting the body was likely to be related to encountering the dead wombat and being stimulated to investigate it. Wombats are interested in their dead. We found that Southern hairy-nosed wombats of a warren often inspected the body of a wombat that died there. Such interest may help wombats understand death as something different from life. [ABSTRACT FROM AUTHOR]

Canine leishmaniasis is a widespread disease on the American continent, with cases reported from Uruguay to the USA and Canada. While numerous Leishmania spp. have been reported in dogs in this region, Leishmania infantum and Leishmania braziliensis are the most common etiological agents of canine leishmaniasis from a continental perspective. Nonetheless, other species may predominate locally in some countries. The participation of dogs in the transmission cycle of various Leishmania spp. has long been speculated, but evidence indicates that their role as reservoirs of species other than L. infantum is negligible. Various native wildlife (e.g., small rodents, marsupials, sloths, and monkeys) are, in fact, the primary hosts of Leishmania spp. in the Americas. In this review, an updated list of Leishmania spp. infecting dogs in the Americas is presented, along with their distribution and clinical and zoonotic importance [ABSTRACT FROM AUTHOR]

Tropical forests and savannahs worldwide are yielding to agribusiness, impacting biodiversity. In the southern Amazon deforestation arc, deforestation progress and limited study of extensive areas result in knowledge gaps on the impacts on biodiversity. We examined patterns of small-bodied mammal species diversity along a gradient ranging from closed-canopy to open-area savannahs, in the Guaporé river basin, Brazil. During one temporal replica—between December 2011 and October 2012—we sampled small mammals using live-traps in seven sites along three 1 km transects each. We assessed and predicted species alpha-diversity (within site), beta-diversity (unshared between sites), and zeta-diversity (shared) across the gradient, relating each biodiversity facets to the sites habitat structure, including vegetation height and above-ground biomass. From 202 individuals recorded, we uncovered 18 species in the region, whereas alpha-diversity was similar between sites, the species composition discretely shifted from non-floodable terra firme to open-areas of the transition zone southwards. Sites located at the intermediary zones of the north–south axis had lower beta-diversity contributions in comparison with northern- and southernmost sites, suggesting mixed biome influences. Zeta-diversity declined rapidly from closer sites to the more distant ones. Along the middle Guaporé basin, small mammal distribution correspondingly reflected the influence of the Cerrado and Amazon. Species presence—and cryptic diversity in terms of species not recorded yet—highlights conserving extensive habitats to accommodate diverse regional-local diversity needs, whereas both beta- and zeta-diversity patterns reveal that sites distinctiveness and multiple assemblages are required to safeguard the regional-scale diversity. [ABSTRACT FROM AUTHOR]

Understanding animal behavioural patterns can provide insight into how populations and communities are adapting to broader environmental shifts. The northern quoll (Dasyurus hallucatus), an endangered marsupial predator, has traditionally been classified as nocturnal. However, evidence is emerging that such simple classifications belie the complexity of animal activity patterns. Using time‐stamped camera trap imagery and fine‐scale accelerometer data, our study explores the diel activity patterns of northern quolls across their range in northern Australia. Contrary to the conventional nocturnal classification, we found that the northern quoll used bimodal activity patterns in four of the five populations examined in this study. Activity and accelerometer data showed two nightly movement peaks, with a distinctive lull around midnight, a pattern similar to one displayed by other marsupial predators. We found no consistent effect of season or lunar phase on temporal activity. Instead, its possible temporal activity patterns are primarily influenced by factors not accounted for here, such as prey availability, climate, predator avoidance, or energy expenditure related to digestion. We suggest further research incorporating these factors will improve our understanding of northern quoll behaviour. [ABSTRACT FROM AUTHOR]

In Mexico opossums are difficult to find, and much of their natural history, ecology, and behavior are unknown. Through photographic and visual records, we obtained data on the presence of two species of marsupials in southern Mexico. We report new municipal records of Derby's woolly opossum, Caluromys derbianus in Veracruz, and new municipal records of the Gray four-eyed opossumPhilander opossum for Oaxaca, Veracruz, and Chiapas. Local mammal records are crucial for understanding the biology and ecology of species, as well as identifying its threats. [ABSTRACT FROM AUTHOR]

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Deforestation remains the most pervasive driver of biodiversity erosion across tropical forests. Understanding how species can cope with such habitat changes is particularly important along the rapidly expanding agricultural frontiers. To do so, we used a functional perspective examining small mammal responses to habitat loss, fragmentation, and degradation across the 'Arc of Deforestation' in the Southern Brazilian Amazon. Small mammals were surveyed using a combination of conventional and pitfall traps across 20 forest fragments—ranging from 42 to 4743 ha—in addition to two relatively continuous forest sites (> 7000 ha). These fragments lie isolated by a cattle pasture matrix of varying grazing intensity. We then analysed taxonomic and functional diversity patterns—represented by Simpson Diversity and Rao Quadratic entropy indices—in Generalised Linear Models containing local- to landscape-scale predictors of variation. Further, we used a functional trait composition approach based on community-weighted mean trait values to depict and predict small mammal functional variations across this degradation gradient. From a total of 847 individuals recorded belonging to 24 taxa, functional responses tended to follow the taxonomic diversity, both increasing with fragment area. The functional dimension further was promoted by low fire-related disturbance. Functional trait composition was mainly driven by habitat quality, represented by tree density, arthropod biomass, and fire-related disturbance. Our results reinforce that small forest fragments sustain depauperate small mammal assemblages both taxonomically and functionally. Accounting for habitat quality further allows for boosting the persistence across functional groups. Our findings can be used to improve the efficiency of management practices thereby maximising the multiple dimensions of small mammal diversity and their associated ecosystem services across tropical deforestation frontiers. [ABSTRACT FROM AUTHOR]

We record and analyze the movement patterns of the marsupial Didelphis aurita at different temporal scales. Animals trajectories are collected at a daily scale by using spool-and-line techniques and, with the help of radio-tracking devices, animals traveled distances are estimated at intervals of weeks. Small-scale movements are well described by truncated Lévy flight, while large-scale movements produce a distribution of distances which is compatible with a Brownian motion. A model of the movement behavior of these animals, based on a truncated Lévy flight calibrated on the small scale data, converges towards a Brownian behavior after a short time interval of the order of 1 week. These results show that whether Lévy flight or Brownian motion behaviors apply, will depend on the scale of aggregation of the animals paths. In this specific case, as the effect of the rude truncation present in the daily data generates a fast convergence towards Brownian behaviors, Lévy flights become of scarce interest for describing the local dispersion properties of these animals, which result well approximated by a normal diffusion process and not a fast, anomalous one. Interestingly, we are able to describe two movement phases as the consequence of a statistical effect generated by aggregation, without the necessity of introducing ecological constraints or mechanisms operating at different spatio-temporal scales. This result is of general interest, as it can be a key element for describing movement phenomenology at distinct spatio-temporal scales across different taxa and in a variety of systems. [ABSTRACT FROM AUTHOR]

A new study presents evidence of sex-related sleep reduction in males of two marsupial mice species but not in females. The growing experimental data suggest that seasonal sleep reduction, linked to migrations and reproductive periods, is common among animals. [ABSTRACT FROM AUTHOR]

Tree-kangaroos (genus Dendrolagus) are a morphologically distinctive genus of specialized, arboreal macropodids confined to the wet forests of New Guinea and northeast Australia. A distinct Goodfellow’s group, containing up to four species, has long been recognized. Resolving the relationships of taxa within the group has been hampered by limited samples of most taxa. Here we supplement published genetic data from high quality tissue samples with molecular data generated from museum specimens to improve taxon and geographic coverage. This includes specimens of the previously unsampled D. g. goodfellowi, the holotype and paratype of D. deltae, and additional specimens of D. matschiei, D. spadix and D. g. buergersi. DNA sequence data were generated from three mitochondrial loci. Phylogenetic analysis improved the resolution of relationships within the Goodfellow’s group, with the morphologically similar D. g. goodfellowi and D. g. buergersi being recovered as sister taxa, while D. pulcherrimus was the sister to the closely related, but morphologically and ecologically distinct, D. spadix and D. matschiei. Despite being sister to D. g. buergersi, D. g. goodfellowi was highly divergent. However, the two are morphologically very similar and we recommend retaining the taxonomic status quo (recognizing them as two subspecies of a single species) until improved sampling and a more thorough analysis is possible. The problematic D. deltae was confirmed as a junior synonym of D. matschiei. [ABSTRACT FROM AUTHOR]