Although antibiotic resistance is a major issue for both human and animal health, very few studies have investigated the role of the bacterial host spectrum in its dissemination within natural ecosystems. Here, we assessed the prevalence of methicillin resistance among Staphylococcus aureus (MRSA) isolates from humans, non-human primates (NHPs), micromammals and bats in a primatology center located in southeast Gabon, and evaluated the plausibility of four main predictions regarding the acquisition of antibiotic resistance in this ecosystem. MRSA strain prevalence was much higher in exposed species (i.e., humans and NHPs which receive antibiotic treatment) than in unexposed species (micromammals and bats), and in NHP species living in enclosures than those in captivity-supporting the assumption that antibiotic pressure is a risk factor in the acquisition of MRSA that is reinforced by the irregularity of drug treatment. In the two unexposed groups of species, resistance prevalence was high in the generalist strains that infect humans or NHPs, supporting the hypothesis that MRSA strains diffuse to wild species through interspecific transmission of a generalist strain. Strikingly, the generalist strains that were not found in humans showed a higher proportion of MRSA strains than specialist strains, suggesting that generalist strains present a greater potential for the acquisition of antibiotic resistance than specialist strains. The host spectrum is thus a major component of the issue of antibiotic resistance in ecosystems where humans apply strong antibiotic pressure.

Coxiella burnetii, the causal agent of human Q fever and animal Coxiellosis, is a zoonotic infectious bacterium with a complex ecology that results from its ability to replicate in multiple (in)vertebrate host species. Spain notifies the highest number of Q fever cases to the ECDC annually and wildlife plays a relevant role in C. burnetii ecology in the country. However, the whole picture of C. burnetii hosts is incomplete, so this study seeks to better understand the role of micromammals in C. burnetii ecology in the country. Spleen samples from 816 micromammals of 10 species and 130 vaginal swabs from Microtus arvalis were analysed by qPCR to detect C. burnetii infection and shedding, respectively. The 9.7% of the spleen samples were qPCR positive. The highest infection prevalence (10.8%) was found in Microtus arvalis, in which C. burnetii DNA was also detected in 1 of the 130 vaginal swabs (0.8%) analysed. Positive samples were also found in Apodemus sylvaticus (8.7%), Crocidura russula (7.7%) and Rattus rattus (6.4%). Positive samples were genotyped by coupling PCR with reverse line blotting and a genotype II+ strain was identified for the first time in one of the positive samples from M. arvalis, whereas only partial results could be obtained for the rest of the samples. Acute Q fever was diagnosed in one of the researchers that participated in the study, and it was presumably linked to M. arvalis handling. The results of the study are consistent with previous findings suggesting that micromammals can be infected by C. burnetii. Our findings additionally suggest that micromammals may be potential sources to trace back the origin of human Q fever and animal Coxiellosis cases in Europe.

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For organisms to survive and prosper in a harsh environment, particularly under rapid climate change, poses tremendous challenges. Recent studies have highlighted the continued loss of megafauna in terrestrial ecosystems and the subsequent surge of small mammals, such as rodents, bats, lagomorphs, and insectivores. However, the ecological partitioning of these animals will likely lead to large variation in their responses to environmental change. In the present study, we investigated the evolutionary history and genetic adaptations of white-bellied rats (Niviventer Marshall, 1976), which are widespread in the natural terrestrial ecosystems in Asia but also known as important zoonotic pathogen vectors and transmitters. The southeastern Qinghai-Tibet Plateau was inferred as the origin center of this genus, with parallel diversification in temperate and tropical niches. Demographic history analyses from mitochondrial and nuclear sequences of Niviventer demonstrated population size increases and range expansion for species in Southeast Asia, and habitat generalists elsewhere. Unexpectedly, population increases were seen in N. eha, which inhabits the highest elevation among Niviventer species. Genome scans of nuclear exons revealed that among the congeneric species, N. eha has the largest number of positively selected genes. Protein functions of these genes are mainly related to olfaction, taste, and tumor suppression. Extensive genetic modification presents a major strategy in response to global changes in these alpine species.

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In this study, we provide the first taphonomic and taxonomic descriptions of the micromammals from Misliya Cave, where recently a Homo sapiens hemimaxilla has been reported. This finding significantly extends the time frame for the out-of-Africa presence of anatomically modern humans. It also provides an opportunity to reassess variation in early modern human population responses to climate change in the Levantine sequence. Information on species ranking and diversity estimations (Shannon functions) is obtained from quantitative data across 31 Levantine assemblages and investigated in a broad comparative frame using multivariate analyses. Recent models of human-climate interactions in the late Early-Middle Paleolithic of the southern Levant have drawn heavily on on-site associations of human fossils with remains of micromammals. However, there has been little, if any, attempt to examine the long-term picture of how paleocommunities of micromammals responded qualitatively and quantitatively to climatic oscillations of the region by altering their compositional complexity. Consequently, our understanding is vastly limited in regard to the paleoecosystem functions that linked past precipitation shifts to changes in primary producers and consumers or as to the background climatic conditions that allowed for the development of highly nonanalog ancient communities in the region. Although previous studies argued for a correspondence between alternations in H. sapiens and Neanderthal occupations of the Levant and faunal shifts in key biostratigraphic indicator taxa (such as Euro-Siberian Ellobius versus Saharo-Arabian Mastomys and Arvicanthis), our data indicate the likelihood that early H. sapiens populations (Misliya and Qafzeh hominins) persisted through high amplitudes of paleoecological and climatic oscillations. It is unlikely, given these results, that climate functioned as a significant filter of early modern human persistence and genetic interactions with Neanderthals in the Levant.

The spectrum of glacial-interglacial environmental shifts in the southern Levant Mediterranean zone is evaluated based upon carbon isotopic records of speleothems from several caves, faunal records of Middle Paleolithic and Upper Paleolithic layers in caves, together with additional evidence from the base levels of the region. The studied evidence suggests that food resources were commonly abundant, but some water scarcity and increase in summer rains occurred during MIS 5e, when soils and C3 vegetation were eliminated, causing soil erosion. This was followed by penetration of summer rainfall and lightning storms from the south, and associated C4 vegetation and fires. Faunal resources remained abundant, and humans using the southern Levant corridor enjoyed also a favorable passage through the greening Sahara Desert during MIS 5e, which was crucial for human and faunal dispersion. Qafzeh and Rantis caves\' environmental records indicate xeric grassland-type ecosystem with Afro-Arabian elements that can be attributed to MIS 5e. As the environmental conditions of MIS 5e were unique, faunal and isotopic records within this region can be used in the future as chronologic markers for MIS 5e. During the last glacial period, conditions became gradually cooler and wetter, and C3 vegetation dominated the Mediterranean zone. Lower temperatures promoted the entry of Palearctic mammals. Fluctuations of speleothem δ13C increased during the latest Pleistocene - early Holocene, indicating environmental instability through the deglaciation. Significantly, the δ13C records indicate that vegetation did not change from the last glacial period to the Holocene in spite of the observed fluctuations. The extreme environmental event of MIS 5e was not repeated during the Holocene in terms of natural vegetation and fauna. Anthropogenic environmental change, accelerating towards the present, is overriding the natural trend.

It is widely believed that Byzantine agriculture in the Negev Desert (fourth to seventh century Common Era; CE), with widespread construction of terraces and dams, altered local landscapes. However, no direct evidence in archaeological sites yet exists to test this assumption. We uncovered large amounts of small mammalian remains (rodents and insectivores) within agricultural installations built near fields, providing a new line of evidence for reconstructing anthropogenic impact on local habitats. Abandonment layers furnished high abundances of remains, whereas much smaller numbers were retrieved from the period of human use of the structures. Digestion marks are present in low frequencies (20% of long bones and teeth), with a light degree of impact, which indicate the role of owls (e.g. Tyto alba) as the principal means of accumulation. The most common taxa-gerbils (Gerbillus spp.) and jirds (Meriones spp.)-occur in nearly equal frequencies, which do not correspond with any modern Negev communities, where gerbils predominate in sandy low-precipitation environments and jirds in loessial, higher-precipitation ones. Although low-level climate change cannot be ruled out, the results suggest that Byzantine agriculture allowed jirds to colonize sandy anthropogenic habitats with other gerbilids and commensal mice and rats.

The field of ancient DNA (aDNA) has recently been in a state of exponential growth, largely driven by the uptake of Next Generation Sequencing (NGS) techniques. Much of this work has focused on the mammalian megafauna and ancient humans, with comparatively less studies looking at micromammal fauna, despite the potential of these species in testing evolutionary, environmental and taxonomic theories. Several factors make micromammal fauna ideally suited for aDNA extraction and sequencing. Micromammal subfossil assemblages often include the large number of individuals appropriate for population level analyses, and, furthermore, the assemblages are frequently found in cave sites where the constant temperature and sheltered environment provide favourable conditions for DNA preservation. This review looks at studies that include the use of aDNA in molecular analysis of micromammal fauna, in order to examine the wide array of questions that can be answered in the study of small mammals using new palaeogenetic techniques. This study highlights the bias in current aDNA studies and assesses the future use of aDNA as a tool for the study of micromammal fauna.