Miniopterus Natalensis Research Articles

Evaluation of Taxonomic Characteristics of Matlo and Phala Bat Rabies-Related Lyssaviruses Identified in South Africa.

We report the genetic characterization of two potentially novel rabies-related lyssaviruses identified from bats in Limpopo province, South Africa. Matlo bat lyssavirus (MBLV) was identified in two Miniopterus natalensis (Natal long-fingered) bats in 2015 and 2016, and Phala bat lyssavirus (PBLV) was identified in a Nycticeinops schlieffeni (Schlieffen's) bat in 2021. The distribution of both of these bat species is largely confined to parts of Africa, with limited reports from the Arabian Peninsula. MBLV and PBLV were demonstrated to group with the unassigned and phylogroup I lyssaviruses, respectively. MBLV was most closely related to Lyssavirus caucasicus (WCBV), whereas PBLV was most closely related to Lyssavirus formosa (TWBLV-1) and Taiwan bat lyssavirus 2 (TWBLV-2), based on analysis of the N and G genes, the concatenated N + P + M + G + L coding sequence, and the complete genome sequence. Based on our analysis, MBLV and WCBV appeared to constitute a phylogroup separate from Lyssavirus lleida (LLEBV) and Lyssavirus ikoma (IKOV). Analysis of the antigenic sites suggests that PBLV will likely be serologically distinguishable from established lyssaviruses in virus-neutralization tests, whereas MBLV appeared to be antigenically highly similar to WCBV. Taken together, the findings suggested that, while PBLV is likely a new lyssavirus species, MBLV is likely related to WCBV.

Comparison of microsatellite distribution in the genomes of Pteropus vampyrus and Miniopterus natalensis (Chiroptera)

BackgroundMicrosatellites are a ubiquitous occurrence in prokaryotic and eukaryotic genomes. Microsatellites have become one of the most popular classes of genetic markers due to their high reproducibility, multi-allelic nature, co-dominant mode of inheritance, abundance and wide genome coverage. We characterised microsatellites in the genomes and genes of two bat species, Pteropus vampyrus and Miniopterus natalensis. This characterisation was used for gene ontology analysis and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment of coding sequences (CDS).ResultsCompared to M. natalensis, the genome size of P. vampyrus is larger and contains more microsatellites, but the total diversity of both species is similar. Mononucleotide and dinucleotide repeats were the most diverse in the genome of the two species. In each bat species, the microsatellite bias was obvious. The microsatellites with the largest number of repeat motifs in P. vampyrus from mononucleotide to hexanucleotide were (A)n, (AC)n, (CAA)n, (AAAC)n, (AACAA)n and (AAACAA)n, with frequencies of 97.94%, 58.75%, 30.53%, 22.82%, 54.68% and 22.87%, respectively, while in M. natalensis were (A)n, (AC)n, (TAT)n, (TTTA)n, (AACAA)n and (GAGAGG)n, with of 92.00%, 34.08%, 40.36%, 21.83%, 25.42% and 12.79%, respectively. In both species, the diversity of microsatellites was highest in intergenic regions, followed by intronic, untranslated and exonic regions and lowest in coding regions. Location analysis indicated that microsatellites were mainly concentrated at both ends of the genes. Microsatellites in the CDS are thus subject to higher selective pressure. In the GO analysis, two unique GO terms were found only in P. vampyrus and M. natalensis, respectively. In KEGG enriched pathway, the biosynthesis of other secondary metabolites and metabolism of other amino acids in metabolism pathways were present only in M. natalensis. The combined biological process, cellular components and molecular function ontology are reflected in the GO analysis and six functional enrichments in KEGG annotation, suggesting advantageous mutations during species evolution.ConclusionsOur study gives a comparative characterization of the genomes of microsatellites composition in the two bat species. And also allow further study on the effect of microsatellites on gene function as well as provide an insight into the molecular basis for species adaptation to new and changing environments.

Current State of Knowledge of Wind Energy Impacts on Bats in South Africa

The transition to mitigate climate change necessitates a rapid and global diffusion of renewable energy but this should not jeopardise the need to meet similarly important targets for biodiversity. Wind energy is a leading cause of bat mortality globally, yet little is known about the impacts to bats in Africa. I studied these impacts in South Africa to enhance knowledge on wind energy impacts on African bats. I reviewed data from 59 studies published in scientific journals and technical reports of operational monitoring of bat fatalities at wind turbines. Bat fatalities occurred at all operating wind energy facilities in South Africa. Tadarida aegyptiaca accounted for the majority of carcasses, followed by Neoromicia capensis and Miniopterus natalensis. The majority of fatalities were of non-migratory species and occurred between February and April although bats were killed in all months. Bat fatality differed between wind energy facilities in terms of observed fatality/year, estimated fatality/year and estimated fatality/MW/year but these differences could not be explained by broad scale vegetation patterns. Total estimated bat fatality between 2011 and 2020 was 12,601 bats. Mean fatality/MW/year was 2.8 bats. I estimate that between 2013 and 2050, a minimum of 996,974 bats may be killed at South African wind energy facilities. My results present the first estimates of the scale of potential wind energy impacts to bats in South Africa and the African continent.

The Shortfall of Using Locality Records in the Conservation Planning of South African Cavernicolous Bats: The Natal Long-Fingered Bat as a Case Study

<i>African Journal of Wildlife Research</i> is a multidisciplinary journal that has been published since 1971 and covers the scientific, applied, managerial, methodological, and sociological issues related to wildlife research.

Reproductive status affects isotopic niches of Miniopterus natalensis in northeastern South Africa

Abstract The Natal long-fingered bat, Miniopterus natalensis, is an insectivorous, regional migrating species that exhibits sex-specific migration patterns. We explored the variability of isotopic niches using δ13C and δ15N ratios in fur from female and male bats in different reproductive states: pregnant, reproductive (but not pregnant at the time of this study), and nonreproductive females; nonscrotal and scrotal males using Bayesian standard ellipse areas and generalized linear models. Reproductive status was an informative predictor for the observed variation of both δ13C and δ15N ratios. Pregnant females displayed the highest mean δ13C and δ15N ratios and were distinct from other reproductive states. Reproductive females exhibited significantly higher δ15N ratios than nonreproductive females or nonscrotal and scrotal males, which may reflect state-dependent foraging and/or higher metabolic stress. Scrotal males displayed the lowest mean δ13C and δ15N ratios. Nonscrotal males exhibited the broadest isotopic niche, whereas reproductive females had the narrowest isotopic niche. Differences in isotopic niche sizes between the different reproductive groups may relate to variable individual feeding behavior and/or geographically different foraging areas/migratory stopover sites at individual and intraspecific levels in M. natalensis. This suggests that group-living, cave-dwelling bats may employ individual foraging specialization to facilitate coexistence in the broader geographic landscape.

Evolution of CCR5 and CCR2 Genes in Bats Showed Multiple Independent Gene Conversion Events.

Chemokine receptors are an important determinant for the infectiousness of different pathogens, which are able to target the host cells by binding to the extracellular domains of these proteins. This is the mechanism of infection of HIV-1, among other concerning human diseases. Over the past years, it has been shown that two chemokine receptors, CCR2 and CCR5, have been shaped by events of gene conversion in different mammalian lineages, which has been linked to a possible selective advantage against pathogens. Here, by taking advantage of available bat genomes, we present the first insight of CCR2 and CCR5 evolution within the Chiroptera order. In total, four independent events of recombination between CCR2 and CCR5 were detected: two in a single species, Miniopterus natalensis; one in two species from the Rhinolophoidea superfamily; and one in four species from the Pteropodidae family. The regions affected by the gene conversions were generally extensive and always encompassed extracellular domains. Overall, we demonstrate that CCR2 and CCR5 have been subject to extensive gene conversion in multiple species of bats. Considering that bats are known to be large reservoirs of virus in nature, these results might indicate that chimeric CCR2-CCR5 genes might grant some bat species a selective advantage against viruses that rely in the extracellular portions of either CCR2 or CCR5 as gateways into the cell.

African bats in the collection of the National Museum, Prague (Chiroptera). I. Bats from Zambia

A list of 139 specimens of bats belonging to 32 species of eight families originating from Zambia, housed in the collection of the National Museum, Prague, Czech Republic, is presented in a systematical review. The species lists are complemented by comments on distribution and morphometry data. The specimens represent 73 new records (species vs. locality) of bats from Zambia. The collection contains two species new for the Zambian fauna, Afropipistrellus grandidieri and Neoromicia somalica. Two species, Rhinolophus sakejiensis and Chaerephon bivittatus are documented for the second time from Zambia, the former bat for the first time after the species description at all. The record localities of Epomophorus labiatus, Rhinolophus mossambicus, and Neoromicia somalica shift margins of the whole known distribution ranges of these bats. In Epomophorus dobsonii, Nyctinomus aegyptiacus, Glauconycteris variegata, Pipistrellus rusticus, Scotophilus leucogaster, and S. viridis, the collection specimens represent new peripheral records making their distribution range margins more precise. Molecular genetic analysis revealed new distribution extent of particular mitochondrial lineages of the otherwise common species in Zambia, Hipposideros caffer, Nycteris thebaica, and Miniopterus natalensis s.str.

Assessing the extent of land-use change around important bat-inhabited caves

BackgroundModification and destruction of natural habitats are bringing previously unencountered animal populations into contact with humans, with bats considered important zoonotic transmission vectors. Caves and cave-dwelling bats are under-represented in conservation plans. In South Africa, at least two cavernicolous species are of interest as potential zoonotic hosts: the Natal long-fingered bat Miniopterus natalensis and the Egyptian fruit bat Rousettus aegyptiacus. Little information is available about the anthropogenic pressures these species face around important roost sites. Both bats are numerous and widespread throughout the country; land-use changes and urban expansions are a rising concern for both conservation and increased bat-human contact.ResultsOur study addressed this shortfall by determining the extent of land-cover change around 47 roosts between 2014 and 2018 using existing land cover datasets. We determined the land-cover composition around important roost sites (including maternity, hibernacula and co-roosts), distances to urban settlements and assessed the current protection levels of roost localities. We detected an overall 4% decrease in natural woody vegetation (trees) within 5 km buffer zones of all roost sites, with a 10% decrease detected at co-roost sites alone. Agricultural land cover increased the most near roost sites, followed by plantations and urban land-cover. Overall, roosts were located 4.15 ± 0.91 km from urban settlements in 2018, the distances decreasing as urban areas expand. According to the South African National Biodiversity Institute Ecosystem Threat Status assessment, 72% of roosts fall outside of well-protected ecosystems.ConclusionsThe current lack of regulatory protection of cavernicolous bats and their roosts, increasing anthropogenic expansions and proximity to human settlements raises concerns about increased human-bat contact. Furthermore, uncontrolled roost visitation and vandalism are increasing, contributing to bat health risks and population declines, though the extent of roosts affected is yet to be quantified. In an era where pandemics are predicted to become more frequent and severe due to land-use change, our research is an urgent call for the formal protection of bat-inhabited caves to safeguard both bats and humans.

In silico comparative analysis of BRCA2 gene in some selected animal species in Africa

Background: BRCA2 genes are not only found in humans, but in other animal species. BRCA2 gene plays a vital role in maintaining the stability of a cell's genetic information. BRCA2 is considered as a gatekeeper gene; however, if mutated or abnormally expressed, it causes the destruction of normal cell structure and promotes the growth of cancer cells. Objective: This study aimed to assess the differences and similarities of BRCA2 gene from different animal species in Africa through In silico genomics analysis providing further insight on its comparative genomics features. Materials and Methods: Fifteen nucleotide sequences of BRCA2 gene of different mammals and bird species were retrieved from National Centre for Biotechnology Information (NCBI). Multiple sequence alignment was done with MEGA 7.0 software, while identity and similarities were determined by constructing a pairwise comparison. Conserved domains on the sequences were identified with NCB1-CDD. Results: BRCA2 gene was found to be present not only in humans, but other lower animals and birds across African countries. The phylogenetic tree for Homo sapiens BRCA2 gene in Tunisia belongs to the same ecological niche with the Theropithecus gelada BRCA2 gene in Ethiopia and BRCA2 from the same African region has high bootstrap, implying that they share the same homology. Conserved regions identified in the all the sequences were absent in Miniopterus natalensis and most present in Chrysochloris asiatica, Theropithecus gelada, Apaloderma vittatum, Pterocles gutturalis, Rousettus aegyptiacus, Homo sapiens, Echinops telfairi, and Cavia porcellus. Conclusion: Based on the findings obtained from this study, BRCA2 gene in humans and other lower animals, particularly from same region, share the same homology and similarities.

Complete Genome Sequence of Matlo Bat Lyssavirus.

The genus Lyssavirus includes rabies virus as well as multiple diverse and recently described novel species. Using next-generation sequencing technologies, we have obtained the whole-genome sequence of Matlo bat lyssavirus, which was isolated from a Natal long-fingered bat (Miniopterus natalensis) in South Africa.

No Evidence of Pre-Hibernation or Pre-Migratory Body Mass Gain in Miniopterus natalensis in North-Eastern South Africa

Migration and hibernation are survival strategies that require physiological preparation using fattening. Bats employ both strategies in times of resource shortages. However, because males and females vary seasonally in their reproductive physiological needs, they may employ different fattening patterns. Whilst fattening, migration and hibernation are common in temperate bats, little is known about subtropical migratory insectivores. This study investigated seasonal variation in body mass of the regionally migrating Natal long-fingered bat Miniopterus natalensis to determine if males and females show fattening in preparation for migration/hibernation. Seasonal change best explained the variation observed in overall body mass, whilst sex and forearm length explained the variation to a lesser extent. Body mass between males and females differed significantly by reproductive category among the four seasons. Forearm length was a significant predictor of the body mass of males. Scrotal males had a higher body mass in summer compared to autumn. This pattern of mass gain was not observed in non-scrotal males. The summer body mass of nonpregnant and post-lactating females was not significantly higher than the autumn body mass of nonpregnant females, which did not support the hypothesis that females would exhibit fattening during summer before migration. Results suggest that males and females employ different mass-gain strategies related to reproductive investment rather than fattening preparation for migration or hibernation.

Threat analysis of modelled potential migratory routes forMiniopterus natalensisin South Africa

AbstractMigrant cave‐dwelling insectivores that rely on specific caves for maternity and hibernation, like the Natal long‐fingered batsMiniopterus natalensisin South Africa, may be at particular risk of population decline in an urbanising world. As a step towards the conservation of caves and cave‐dwelling bats in South Africa, this study aimed to (i) broadly identify the number of caves used by bats (any species) and specificallyM. natalensis, throughout South Africa, (ii) investigate the number of maternity and hibernacula roosts currently known forM. natalensis, (iii) assess the number of caves located in formal protected areas, (iv) determine potential migration paths/corridors between hibernacula and maternity sites and (v) evaluate the potential threats (like onshore wind facilities) along potential migratory routes. A meta‐analysis of scientific literature and websites was conducted to identify caves throughout South Africa and locations of maternity and hibernacula roosts forM. natalensis. Roosts were assessed to determine whether (i) they were located in protected areas, (ii) they were used for eco‐tourism and (iii) the distance to primary roads and onshore wind energy facilities. Next, likely migratory paths were modelled between maternity and hibernacula sites using least‐cost path analysis and the threats along potential routes were investigated. A total of 92 caves were identified, 50 were reported to contain bats.M. natalensiswere recorded in 37 caves, and of those, only 9% are currently located inside protected areas. A total of 12 least‐cost paths were modelled, and various paths intersected potential threat risk elements. Our analysis provides the first description of the potential migration corridors forM. natalensisin South Africa, as well as the current conservation status of bat‐inhabited caves. For a developing country set to experience increased urbanisation pressures, this study highlights the need for conservation measures for South African caves and the dependent bats.

Compositional turnover in ecto- and endoparasite assemblages of an African bat, Miniopterus natalensis (Chiroptera, Miniopteridae): effects of hierarchical scale and host sex.

We studied the compositional turnover in infracommunities and component communities of ecto- and endoparasites infesting a bat, Miniopterus natalensis (Chiroptera, Miniopteridae), across seven sampling sites using the zeta diversity metric (measuring similarity between multiple communities) and calculating zeta decline and retention rate (both scales) and zeta decay (component communities). We asked whether the patterns of zeta diversity differ between (a) infracommunities and component communities; (b) ecto- and endoparasites and (c) subsets of communities infecting male and female bats. The pattern of compositional turnover differed between infracommunities and component communities in endoparasites only. The shape of zeta decline for infracommunities indicated that there were approximately equal probabilities of ecto- and endoparasitic species to occur on/in any bat individual within a site. The shape of zeta decline for component communities suggested the stochasticity of ectoparasite turnover, whereas the turnover of endoparasites was driven by niche-based processes. Compositional turnover in component communities of ectoparasites was more spatially dependent than that of endoparasites. Spatial independence of compositional turnover in endoparasites was due to subcommunities harboured by female bats. We conclude that the patterns of compositional turnover in infracommunities were similar in ecto- and endoparasites, whereas the patterns of turnover in component communities differed between these groups.

Temperature explains variation in seasonal temporal activity of Miniopterus natalensis more than moonlight or humidity

Animals partition their daily activities based on a variety of internal and external factors. For insectivorous bats, the availability of prey, weather conditions, moonlight and reproductive energy demands are proposed as the major influencers of temporal activity. This study investigated the temporal variation in activity of the subtropical cave-dwelling, migratory Natal long-fingered bat, Miniopterus natalensis, by temperature, humidity, lunar illumination and the time of moonrise per night. Using echolocation survey data collected 2014–2018 near a maternity roost in north-eastern South Africa, differences in activity between the summer maternity (1 September–28 February) and winter non-breeding (1 March–31 August) seasons were described. In the non-breeding season, M. natalensis exhibited peak activity during the early evening, with decreasing activity throughout the night. In the maternity season, a bimodal activity pattern was observed, probably related to peaks in insect activity and the energy requirements of lactating females. Predictably, temperature had the strongest positive influence on the magnitude of M. natalensis activity across both seasons. Humidity also positively affected activity in both seasons to a lesser extent. The time of moonrise did not affect the activity of M. natalensis during either of the seasons. Lunar illumination did not affect activity during the maternity season, but activity was diminished on nights with bright moonlight in the non-breeding season. Emergence and return times were not affected by lunar illumination in either season. The need of M. natalensis to maximise resource acquisition during the maternity season is likely a strong modulator in the temporal activity of this species and outweighs predation risk in high moonlight conditions. Subsequently, this species exhibits nightly activity behaviours that balance risk factors with intrinsic needs during different seasons.

Differential cellular proliferation underlies heterochronic generation of cranial diversity in phyllostomid bats

BackgroundSkull diversity in the neotropical leaf-nosed bats (Phyllostomidae) evolved through a heterochronic process called peramorphosis, with underlying causes varying by subfamily. The nectar-eating (subfamily Glossophaginae) and blood-eating (subfamily Desmondontinae) groups originate from insect-eating ancestors and generate their uniquely shaped faces and skulls by extending the ancestral ontogenetic program, appending new developmental stages and demonstrating peramorphosis by hypermorphosis. However, the fruit-eating phyllostomids (subfamilies Carollinae and Stenodermatinae) adjust their craniofacial development by speeding up certain developmental processes, displaying peramorphosis by acceleration. We hypothesized that these two forms of peramorphosis detected by our morphometric studies could be explained by differential growth and investigated cell proliferation during craniofacial morphogenesis.ResultsWe obtained cranial tissues from four wild-caught bat species representing a range of facial diversity and labeled mitotic cells using immunohistochemistry. During craniofacial development, all bats display a conserved spatiotemporal distribution of proliferative cells with distinguishable zones of elevated mitosis. These areas were identified as modules by the spatial distribution analysis. Ancestral state reconstruction of proliferation rates and patterns in the facial module between species provided support, and a degree of explanation, for the developmental mechanisms underlying the two models of peramorphosis. In the long-faced species, Glossophaga soricina, whose facial shape evolved by hypermorphosis, cell proliferation rate is maintained at lower levels and for a longer period of time compared to the outgroup species Miniopterus natalensis. In both species of studied short-faced fruit bats, Carollia perspicillata and Artibeus jamaicensis, which evolved under the acceleration model, cell proliferation rate is increased compared to the outgroup.ConclusionsThis is the first study which links differential cellular proliferation and developmental modularity with heterochronic developmental changes, leading to the evolution of adaptive cranial diversity in an important group of mammals.

Faecal analyses and alimentary tracers reveal the foraging ecology of two sympatric bats.

We used three complementary methods to assess the diet of two insectivorous bat species: one an obligate aerial hunter, Miniopterus natalensis, and the other Myotis tricolor whose morphology and taxonomic affiliation to other trawling bats suggests it may be a trawler (capturing insects from the water surface with its feet and tail). We used visual inspection, stable isotope values and fatty acid profiles of insect fragments in bat faeces sampled across five sites to determine the contribution of aquatic and terrestrial arthropods to the diets of the two species. The niche widths of M. tricolor were generally wider than those of Miniopterus natalensis but with much overlap, both taking aquatic and terrestrial insects, albeit in different proportions. The diet of M. tricolor had high proportions of fatty acids (20:5ω3 and 22:6ω3) that are only obtainable from aquatic insects. Furthermore, the diet of M. tricolor had higher proportions of water striders (Gerridae) and whirligig beetles (Gyrinidae), insects obtainable via trawling, than Miniopterus natalensis. These results suggest both species are flexible in their consumption of prey but that M. tricolor may use both aerial hawking and trawling, or at least gleaning, to take insects from water surfaces. The resultant spatial segregation may sufficiently differentiate the niches of the two species, allowing them to co-exist. Furthermore, our results emphasize that using a combination of methods to analyse diets of cryptic animals yields greater insights into animal foraging ecology than any of them on their own.

Climatic correlates of migrant Natal long-fingered bat (Miniopterus natalensis) phenology in north-eastern South Africa

Abstract ContextFor migratory animals, particularly those with long generation times, changing weather patterns may cause a mismatch between periods of expected and actual resource availability, termed phenological mismatch. The cave-dwelling Natal long-fingered bat (Miniopterus natalensis) is a regional migrant within South Africa for which the (hitherto unknown) phenology of migration may be affected by climate. AimsTo investigate the migration phenology of the Natal long-fingered bat in relation to climate at a maternity cave in South Africa. MethodsFive years (2014–18) of echolocation data from a maternity cave site in Limpopo, South Africa, were studied. Separate stepwise General Linear Models (GLMs) were constructed for each season using photoperiod, minimum temperature, dew point, rainfall, barometric pressure, humidity and maximum wind speed. Arrival and departure dates among years were also compared. Key resultsPhotoperiod had the greatest effect on the magnitude of Natal long-fingered bat phenological patterns in activity across all seasons. Although spring (September - November) arrival at the maternity site was variable across years, summer departure dates did not differ, resulting in a shorter breeding period in the 2017–18 sample year. During the 2016–17 sample year, the magnitude of Natal long-fingered bat activity was significantly lower than in other years, which coincided with El Niño-induced drought conditions and likely impacted resources and led to a reduction in activity and population size. ConclusionsPhotoperiod is a strong predictive cue of the phenology of migration of the Natal long-fingered bat and likely cues migration for this species. The narrow departure dates of these bats from the maternity site supports these results. ImplicationsThe present study indicates that Natal long-fingered bats use photoperiod as a migration cue and do not appear to shift their spring–summer breeding season, likely making them vulnerable to phenological mismatch and population decline. The research highlights the need for systematic population monitoring for the Natal long-fingered bat.

Increased Body Mass Supports Energy Compensation Hypothesis in the Breeding Female Natal Long-Fingered Bat Miniopterus Natalensis

Lactation is one of the most energetically demanding periods in the life cycle of a small mammal. Classified as income breeders, hibernating small colonial insectivorous bats are hypothesised to compensate for the energetic demand of lactation by increasing daily food intake, which increases body mass. The Natal long-fingered bat Miniopterus natalensis is a colonial hibernating species in southern Africa for which energy compensation was hitherto unknown. We tested predictions of the energy compensation hypothesis using a wild population of M. natalensis during the parturition and maternity period of November–December in 2015–2017. The study was conducted at the Meletse Bat Research and Conservation Training Centre near Gatkop Cave, in Limpopo Province, South Africa. We weighed and categorised 2,707 M. natalensis females captured during evenings and mornings into one of four groups including not pregnant with a sclerotized nipple (NP-SC), not pregnant with a non-sclerotized nipple (NP-NSC), lactating with a sclerotized nipple (L-SC), and pregnant with a sclerotized nipple (P-SC). NP-NSC and NP-SC females were classified as non-reproductive, whilst L-SC and P-SC females were classified as active breeders. Results showed that females in the L-SC category were 6% heavier than females in non-reproductive categories (NP-NSC and NP-SC). Pregnant females were 25% heavier than non-reproductive females due, at least in part, to foetus mass, whilst the mean body mass did not differ between females in non-reproductive categories. Whilst the body mass of females in the NP-NSC, NP-SC and L-SC categories did not differ during evening captures, L-SC females showed the biggest mass increase between evening and morning captures. Proportions of females captured from reproductive categories differed among years, with a higher overall proportion of active breeders (70%) in 2017 than either 2016 (33%) or 2015 (31%). This may be related to inter-annual variation in climate and warrants further investigation. Our results suggest female M. natalensis were heavier, on average, during lactation and support the energy compensation hypothesis.

Recent studies on the evolution of mammalian flight using high-throughput sequencing technology

Bats are the only mammals capable of self-powered flight using wings. Critical adaptations for their flight include a pair of dramatically elongated hands (forelimb digits II–V) with broad wing membranes. Although it has been studied for over ten years, the molecular mechanism of bat wing evolution was still uncertain before 2014. Here we reviewed recently significant studies on this topic, which made a great progress on the knowledge of bat wing formation. Thousands of differentially expressed genes and regulatory elements associated with limb development were found by using advanced high-throughput sequencing technology, including whole genome sequencing, RNA-seq and ChIP-seq. Screening out from RNA-seq data, we identified seven key genes that displayed unique expression patterns in embryonic bat wings and feet, compared with mouse fore- and hindlimbs. The expression of all 5 ′ HoxD genes ( Hoxd9–13 ) and Tbx3 , six known crucial transcription factors for limb and digit development, was extremely high and prolonged in the elongating wing area. The expression of Brinp3 (also called Fam5c ), a tumor suppressor, in bat limbs was bat-specific and significantly high in all short digit regions (the thumb and foot digits). Using RNA-seq analysis, Eckalbar et al. found that more than 7000 genes and a few long noncoding RNAs, including Tbx5-as1 and Hottip, were differentially expressed between forelimb and hindlimb in different stages of bat embryos. They also identified thousands of regions that were differentially modified in forelimb and hindlimb by using ChIP-seq analysis and 2796 bat-accelerated regions (BARs) within H3K27ac peaks by using comparative genomics, several of which cluster near limb-associated genes. Booker et al. discovered 166 BARs that overlap H3K27ac and p300 ChIP-seq peaks in mouse embryonic limbs. They further performed a mouse enhancer assay and showed that five Myotis lucifugus BARs drove gene expression in the embryonic mouse limb, with the majority showing differential enhancer activities compared to the mouse orthologous BAR sequences. Specially, one of them (BAR116), which was located telomeric to the HoxD cluster, had robust forelimb expression for the M. lucifugus sequence and no activity for the mouse sequence at the embryonic corresponding stage. Developing limb expression analysis of Hoxd10 - 13 in another species of bats ( Miniopterus natalensis ) showed that a high-forelimb and weak-hindlimb expression for Hoxd10 - 11 , which was similar to the expression trend observed for M. lucifugus BAR116 in mice. All the above results suggest that multiple changes in gene expression patterns and adaptive evolution of gene expression regulators occurred during the evolution of bat wings. Future studies should focus on functions of key developmental genes and bat-accelerated regulators, interactions between them, and pathways involving these genes.

Pinpointing the vesper bat transposon revolution using the Miniopterus natalensis genome.

BackgroundAround 40 million years ago DNA transposons began accumulating in an ancestor of bats in the family Vespertilionidae. Since that time, Class II transposons have been continuously reinvading and accumulating in vespertilionid genomes at a rate that is unprecedented in mammals. Miniopterus (Miniopteridae), a genus of long-fingered bats that was recently elevated from Vespertilionidae, is the sister taxon to the vespertilionids and is often used as an outgroup when studying transposable elements in vesper bats. Previous wet-lab techniques failed to identify Helitrons, TcMariners, or hAT transposons in Miniopterus. Limitations of those methods and ambiguous results regarding the distribution of piggyBac transposons left some questions as to the distribution of Class II elements in this group. The recent release of the Miniopterus natalensis genome allows for transposable element discovery with a higher degree of precision.ResultsHere we analyze the transposable element content of M. natalensis to pinpoint with greater accuracy the taxonomic distribution of Class II transposable elements in bats. These efforts demonstrate that, compared to the vespertilionids, Class II TEs are highly mutated and comprise only a small portion of the M. natalensis genome. Despite the limited Class II content, M. natalensis possesses a limited number of lineage-specific, low copy number piggyBacs and shares several TcMariner families with vespertilionid bats. Multiple efforts to identify Helitrons, one of the major TE components of vesper bat genomes, using de novo repeat identification and structural based searches failed.ConclusionsThese observations combined with previous results inform our understanding of the events leading to the unique Class II element acquisition that characterizes vespertilionids. While it appears that a small number of TcMariner and piggyBac elements were deposited in the ancestral Miniopterus + vespertilionid genome, these elements are not present in M. natalensis genome at high copy number. Instead, this work indicates that the vesper bats alone experienced the expansion of TEs ranging from Helitrons to piggyBacs to hATs.Electronic supplementary materialThe online version of this article (doi:10.1186/s13100-016-0071-y) contains supplementary material, which is available to authorized users.