Complete mitochondrial genome of a bat-eared fox (Otocyon megalotis), along with phylogenetic considerations

The bat-eared fox, Otocyon megalotis, is the only member of its genus and is thought to occupy a basal position within the dog family. These factors can lead to challenges in complete mitochondrial reconstructions and accurate phylogenetic positioning. Here, we present the first complete mitochondrial genome of the bat-eared fox recovered using shotgun sequencing and iterative mapping to three distantly related species. Phylogenetic analyses placed the bat-eared fox basal in the Canidae family within the clade including true foxes (Vulpes) and the raccoon dog (Nyctereutes) with high support values. This position is in good agreement with previously published results based on short fragments of mitochondrial and nuclear genes, therefore adding more support to the basal positioning of the bat-eared fox within Canidae.The European Research Council (consolidator grant GeneFlow # 310763 to M.H), National Research Foundation (NRF, South Africa), Ministry of Economy and Competitiveness (MINECO, Spain), and Swedish Research Council Formas (Sweden).http://www.tandfonline.com/loi/tmdn20am2017Mammal Research InstituteZoology and Entomolog

Resources and predation: drivers of sociality in a cyclic mesopredator

In socially fexible species, the tendency to live in groups is expected to vary through a trade-of between costs and benefts, determined by ecological conditions. The Resource Dispersion Hypothesis predicts that group size changes in response to patterns in resource availability. An additional dimension is described in Hersteinsson’s model positing that sociality is further afected by a cost–beneft trade-of related to predation pressure. In the arctic fox (Vulpes lagopus), group-living follows a regional trade-of in resources’ availability and intra-guild predation pressure. However, the efect of local fuctuations is poorly known, but ofers an unusual opportunity to test predictions that difer between the two hypotheses in systems where prey availability is linked to intra-guild predation. Based on 17-year monitoring of arctic fox and cyclic rodent prey populations, we addressed the Resource Dispersion Hypothesis and discuss the results in relation to the impact of predation in Hersteinsson’s model. Group-living increased with prey density, from 7.7% (low density) to 28% (high density). However, it remained high (44%) despite a rodent crash and this could be explained by increased benefts from cooperative defence against prey switching by top predators. We conclude that both resource abundance and predation pressure are factors underpinning the formation of social groups in fuctuating ecosystems.publishedVersio

Status and conservation goals for the critically endangered Arctic fox in Scandinavia. Is the mission completed?

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Aardwolf population diversity and phylogenetic positioning inferred using complete mitochondrial genomes

The aardwolf (Proteles cristata) is a unique, insectivorous species of the family Hyaenidae. It occupies a disjunct range in eastern and southern Africa and is possibly a remaining member of a historical dog-like hyaena clade. Although both local and global population status and trends are largely unknown, aardwolves are not uncommon in arid grasslands and the IUCN conservation status of Least Concern appears to be justified.However, they are one of the least studied of the four hyaena species,and we have scarce information about the genetic structure of aardwolf populations. Here, we present the first complete aardwolf mitochondrial genomes and provide novel information about aardwolf evolutionary origins and genetic structure within a single population. Through the investigation of complete mitochondrial genomes from five individuals from a single population within South Africa, we find the mitochondrial diversity of this population to be neither particularly high nor low compared to a number of other mammalian species. Moreover, we also provide additional evidence towards the basal position of the aardwolf within Hyaenidae with a divergence time of 13.0 Ma (95% CI 10.1–16.4 Ma) from all other extant hyaena species.The European Research Council, the National Research Foundation (NRF, South Africa), and the Spanish Ministry of Economy and Competitiveness (MINECO).http://www.sawma.co.zaam2020Mammal Research InstituteZoology and Entomolog

Kin encounter rate and inbreeding avoidance in canids

Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1–8% and 20–22% in noninbred and inbred canid populations, respectively. We show that regardless of encounter rate, outside natal groups mates were selected independent of relatedness. Within natal groups, there was a significant avoidance of mating with a relative. Lack of discrimination against mating with close relatives outside packs suggests that the rate of inbreeding in canids is related to the proximity of close relatives, which could explain the high degree of inbreeding depression observed in some populations. The idea that kin encounter rate and social organization can explain the lack of inbreeding avoidance in some species is intriguing and may have implications for the management of populations at risk

Ecological specialization and evolutionary reticulation in extant Hyaenidae

During the Miocene, Hyaenidae was a highly diverse family of Carnivora that has since been severely reduced to four species: the bone-cracking spotted, striped, and brown hyenas, and the specialized insectivorous aardwolf. Previous studies investigated the evolutionary histories of the spotted and brown hyenas, but little is known about the remaining two species. Moreover, the genomic underpinnings of scavenging and insectivory, defining traits of the extant species, remain elusive. Here, we generated an aardwolf genome and analyzed it together with the remaining three species to reveal their evolutionary relationships, genomic underpinnings of their scavenging and insectivorous lifestyles, and their respective genetic diversities and demographic histories. High levels of phylogenetic discordance suggest gene flow between the aardwolf lineage and the ancestral brown/striped hyena lineage. Genes related to immunity and digestion in the bone-cracking hyenas and craniofacial development in the aardwolf showed the strongest signals of selection, suggesting putative key adaptations to carrion and termite feeding, respectively. A family-wide expansion in olfactory receptor genes suggests that an acute sense of smell was a key early adaptation. Finally, we report very low levels of genetic diversity within the brown and striped hyenas despite no signs of inbreeding, putatively linked to their similarly slow decline in effective population size over the last 2 million years. High levels of genetic diversity and more stable population sizes through time are seen in the spotted hyena and aardwolf. Taken together, our findings highlight how ecological specialization can impact the evolutionary history, demographics, and adaptive genetic changes of an evolutionary lineage.The Swedish Research Council and the Knut and Alice Wallenberg Foundation, ERC consolidator grant, an Australian Research Council grant, “Clinician Scientist Programm, Medizinische Fakultat der Universitat Leipzig and Leibniz Competition Fund.https://academic.oup.com/mbeam2022Mammal Research InstituteZoology and Entomolog

The effect of regular walks on various health aspects in older people with dementia: protocol of a randomized-controlled trial

<p>Abstract</p> <p>Background</p> <p>Physical activity has proven to be beneficial for physical functioning, cognition, depression, anxiety, rest-activity rhythm, quality of life (QoL), activities of daily living (ADL) and pain in older people. The aim of this study is to investigate the effect of walking regularly on physical functioning, the progressive cognitive decline, level of depression, anxiety, rest-activity rhythm, QoL, ADL and pain in older people with dementia.</p> <p>Methods/design</p> <p>This study is a longitudinal randomized controlled, single blind study. Ambulatory older people with dementia, who are regular visitors of daily care or living in a home for the elderly or nursing home in the Netherlands, will be randomly allocated to the experimental or control condition. Participants of the experimental group make supervised walks of 30 minutes a day, 5 days a week, as part of their daily nursing care. Participants of the control group will come together three times a week for tea or other sedentary activities to control for possible positive effects of social interaction. All dependent variables will be assessed at baseline and after 6 weeks, and 3, 6, 9, 12 and 18 months of intervention.</p> <p>The dependent variables include neuropsychological tests to assess cognition, physical tests to determine physical functioning, questionnaires to assess ADL, QoL, level of depression and anxiety, actigraphy to assess rest-activity rhythm and pain scales to determine pain levels. Potential moderating variables at baseline are: socio-demographic characteristics, body mass index, subtype of dementia, apolipoprotein E (ApoE) genotype, medication use and comorbidities.</p> <p>Discussion</p> <p>This study evaluates the effect of regular walking as a treatment for older people with dementia. The strength of this study is that 1) it has a longitudinal design with multiple repeated measurements, 2) we assess many different health aspects, 3) the intervention is not performed by research staff, but by nursing staff which enables it to become a routine in usual care. Possible limitations of the study are that 1) only active minded institutions are willing to participate creating a selection bias, 2) the drop-out rate will be high in this population, 3) not all participants will be able to perform/understand all tests.</p> <p>Trial registration</p> <p><a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1482">NTR1482</a></p

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

Genetic analyses of European red foxes reveals multiple distinct peripheral populations and central continental admixture

Temperate terrestrial species in Europe were hypothesized to have been restricted to southern peninsular refugia (Iberia, Italy, Balkans) during the height of the last glacial period. However, recent analyses of fossil evidence indicate that some temperate species existed outside these areas during the last glacial maximum (LGM). Red foxes (Vulpes vulpes) in particular, could have been distributed across the southern half of the continent, potentially forming one continuous population. To investigate these hypotheses, we used 21 nuclear microsatellite loci and two fragments (768 bp) of mitochondrial DNA to characterize the population structure among a continent-wide sample of 288 European red foxes. We tested whether European red foxes clustered into discrete populations corresponding to the hypothetical peninsular refugia. Additionally, we sought to determine if distinct northern populations were formed after post-glacial recolonization. Our results indicated that only the foxes of Iberia appeared to have remained distinct over a considerable period of time (32–104 kya). Spanish red foxes formed their own genotypic cluster; all mtDNA haplotypes were endemic and closely related, and together both the mitochondrial and nuclear datasets indicated this population contributed little to postglacial recolonization of Northern Europe. In contrast, red foxes from Italy and the Balkans contributed significantly to, or were part of, a wider, admixed population stretching across mid-latitude Europe. In Northern Europe, we identified a Scandinavian population that had an ancestral relationship with red foxes to the south, and a more recent relationship with those to the east, in Russia. We also resolved two distinct populations on the islands of Ireland and Britain that had been separated from one another, and from those on the continent, since the late Pleistocene/mid Holocene (~4–24 ky

Phenylation of Platinum(II) Thioether Complexes by Tetraphenylborate(III) in Solid State and Nitromethane Solution

Platinum(II) complexes of the type [Pt(thioether)2Cl]+(thioether = dimethyl sulfide, thioxane) are capable of abstracting a phenyl group from the BPh4 counterion with formation of trans[Pt(thioether)2ClPh] compounds. Thermal reactions proceed both in the solid phase and in nitromethane solution at elevated temperature and have preparative importance. Phenylation of the Pt(II) centre also occurs in reaction between [Pt(Me2S)2Cl2] and AgBPh4 in CH2Cl2 suspension. Brief X-ray crystallographic structural data for trans-[Pt(Me2S)2ClPh] and [Pt(thioether)3Cl]X (thioether = Me2S, tx, X = SO3CF3; thioether = Me2S, X = PF6) are reported