Northern range margin populations of the European fire-bellied toad (Bombina bombina) have rapidly declined during recent decades. Extensive agricultural land use has fragmented the landscape, leading to habitat disruption and loss, as well as eutrophication of ponds. In Northern Germany (Schleswig-Holstein) and Southern Sweden, this decline resulted in decreased gene flow from surrounding populations, low genetic diversity, and a putative reduction in adaptive potential, leaving populations vulnerable to future environmental and climatic changes. Previous studies using mitochondrial control region and nuclear transcriptome-wide SNP data detected introgressive hybridization in multiple northern B. bombina populations after presumed illegal release of toads from Austria. Here, we determine the impact of this introgression by comparing the body conditions (as a proxy for fitness) of introgressed and non-introgressed populations, and the genetic consequences in two candidate genes for putative local adaptation (the MHC II gene as part of the adaptive immune system and the stress response gene HSP70 kDa). We detected regional differences in body condition. We observed significantly elevated levels of within individual MHC allele counts in introgressed Swedish populations, associated with a tendency towards higher body weight, relative to regional non-introgressed populations. These differences were not observed among introgressed and non-introgressed German populations. Genetic diversity in both MHC and HSP was generally lower in northern than southern populations. Our study sheds light on the potential benefits of translocations of more distantly related conspecifics as a means to increase adaptive genetic variability and fitness of struggling range margin populations without distortion of local adaptation.
The coastal heathlands of North-west Europe are valuable cultural landscapes, created and maintained over millennia by a land-use regime involving burning and grazing. These heathlands are now critically threatened throughout their range by land-use change and, increasingly, climatic changes. The climatic change impacts are complex, as the coastal heathland regions are experiencing increased temperature and precipitation, but also increased frequency and severity of extreme events, such as drought. Previous studies reveal that established heathland vegetation, including Calluna, are vulnerable to drought, but also that these vulnerabilities vary throughout the range, and with successional stage after fire. Recruitment from seed is an important regeneration strategy for Calluna heathland vegetation after burning, and our study is the first to assess how the seed germination and early seedling growth of Calluna respond to drought. We will do this in a lab germination experiment, where we will expose Calluna seeds to five different drought treatments, from -0.25 MPa to -1.7 MPa, and measure germination, and record germination percentage, germination rates, and seedling growth, below-ground allocation, and functional traits (Specific Leaf Area, Specific Root Length). To allow assessment of variation in drought responses due to geographic origin, successional stage, and the maternal plants’ drought exposure, we will conduct this experiment on seeds from 540 Calluna plants sampled from across three drought treatments (control, 50%, and 90% coverage), in three successional stages after fire (pioneer, building, mature), in two regions (60N, 65N), using a factorial design.
We sought to generate a preliminary demographic framework for Psammochloa villosa to support of future studies of this ecologically important desert grass species, its conservation, and sustainable utilization. Psammochloa villosa occurs in the Inner Mongolian Plateau where it is frequently the dominant species and is involved in sand stabilization and wind breaking. Here, we characterized the genetic diversity and structure of 210 individuals from 43 natural populations of P. villosa using amplified fragment length polymorphism (AFLP) markers. We obtained 1728 well-defined amplified bands from eight pairs of primers, of which 1654 bands (95.72%) were polymorphic.All these values indicate that there is abundant genetic diversity, but limited gene flow in P. villosa. However, an analysis of molecular variance (AMOVA) showed that genetic variation mainly exists within 43 populations of the species (64.16%), and we found that the most genetically similar populations were often not geographically adjacent. Thus, this suggests that the mechanisms of gene flow are surprisingly complex in the species and may occur over long distances. In addition, we predicted the distribution dynamics of P. villosa based on the spatial distribution modeling and found that its range has contracted continuously since the last inter-glacial period. We speculate that dry, cold climates have been critical in determining the geographic distribution of P. villosa during the Quaternary period. Our study provides new insights into the population genetics and evolutionary history of P. villosa in the Inner Mongolian Plateau, which can be used to design in-situ conservation actions and to prioritize sustainable utilization of germplasm resources.
Amblypygids are an arachnid order possessing a unique pair of spined pedipalps: appendages that perform in prey capture, courtship and contest. Pedipalp length, hypothesised to be under sexual selection, varies markedly across amblypygid species, and pedipalp spination, thought to reflect selection for function in prey capture, also differs interspecifically. Differences in pedipalp shape between species may indicate that the relative strength of selection for prey capture and sexual selection vary across the group. However, interspecific differences in pedipalp shape have not been quantified, due to difficulties in identifying homologous features. For the first time, we quantify trends in amblypygid pedipalp shape complexity. We use elliptical Fourier analysis to quantify 2D complexity in pedipalp outlines across eleven species and six genera. We find that complexity significantly decreases as pedipalp length increases. This appears to be driven by relative spine length, suggesting that a trade-off exists between pedipalp length and spination. Furthermore, significant female-biased sexual dimorphism in shape complexity is present in the tibial segment of the amblypygid pedipalp. Our results provide novel insights into the drivers of amblypygid pedipalp evolution, and suggest that a functional trade-off between performance in prey capture and other functions under sexual selection exist in this enigmatic structure.
Phragmites australis is the dominant species in the Yellow River Delta and plays an important role in wetland ecosystems. Ecological responses of the P. australis community to soil properties were investigated in 96 areas along the coastal-inland regions in the Yellow River Delta of China. The aim was to evaluate the relationship between phenotypic variation and environmental factors, reveal which functional traits could well respond to changes in electrical conductivity and soil water content, and the ecological strategies of P. australis. Within the range of soil water content (9.39–36.92%) and electrical conductivity (0.14–13.29 ms/cm), the results showed that the effects of soil water content and salinity were not equally important for the characterization of the morphological and physiological variability, and that plant functional traits including leaf traits and stem traits responded more strongly to soil salinity than soil water content. Our results suggested that salinity leads to reduced average height, specific leaf area, leaf area, and base stem diameter, but increased leaf water content and leaf thickness. The relationships between functional traits and electrical conductivity were generally linear and logarithmic. The coefficients of variation of morphological traits showed more phenotypic plasticity than the physiological traits. Salinity also led to the stress tolerator/competitor-stress tolerator (S/CS) strategies of P. australis; with the decrease of environmental stress, the main strategy gradually moved to the competitor (C) strategy, making P. australis the dominant species in the Yellow River Delta. KEYWORDS: Soil water content, Electrical conductivity, Functional traits, Plasticity, Life strategies.
1. Metadata plays an essential role in the long term preservation, reuse, and interoperability of data. Nevertheless, creating useful metadata can be sufficiently difficult and weakly-enough incentivised that many datasets may be accompanied by little or no metadata. One key challenge is, therefore, how to make metadata creation easier and more valuable. We present a solution that involves creating domain specific metadata schemes that are as complex as necessary and as simple as possible. These goals are achieved by co-development between a metadata expert and the researchers (i.e. the data creators). The final product is a bespoke metadata scheme into which researchers can enter information (and validate it) via the simplest of interfaces: a web browser application and a spreadsheet. 2.We provide the R package [‘dmdScheme‘](https://CRAN.R-project.org/package=dmdScheme) [@Krug2019] for creating a template domain specific scheme. We describe how to create a domain specific scheme from this template, including the iterative co-development process, and the simple methods for using the scheme, and simple methods for quality assessment, improvement, and validation. 3.The process of developing a metadata scheme following the outlined approach was successful, resulting in a metadata scheme which is used for the data generated in our research group. The validation quickly identifies forgotten metadata, as well as inconsistent metadata, therefore improving the quality of the metadata. Multiple output formats are available, including XML. 4. Making the provision of metadata easier while also ensuring high quality must be a priority for data curation initiatives. We show how both objectives are achieved by very close collaboration between metadata experts and researchers to create domain specific schemes. A near-future priority is to provide methods to interface domain specific schemes with general metadata schemes, such as the Ecological Metadata Language, to increase interoperability.
The study is aimed to investigate the nature and extent, and assess perception of local community towards wildlife. A total of 140 household heads were selected randomly from nine survey villages using structured and semi-structured questionnaire for interviews. Focus group discussion, key informant interview and personal observation were held used to achieve the study objectives. Data were analyzed using descriptive statistics and responses compared using Chi-square test (2 tailed), one-way ANOVA and Pearson correlation coefficient. Besides, Likert scale statements were used to assess the attitudes of local people towards wildlife conservation. About 47.1% of sampled respondents thought that they experienced livestock predation whereas 57(40.7%) of the respondents faced both crop damage and livestock predation problems. A total of 932.43TLU livestock and 218 Dogs losses reported by households due to predators over the last five years. Thus, large numbers (848.6TLU livestock and 218 Dogs) of attack was happened due to Spotted Hyena (Crocuta crocuta). The frequency of livestock predation (F = 8.157, df = 8, P < 0.05) and type of predators involved (χ2=79.719, df = 8, p <0.05) were significantly differ across study villages. Nearly half, 69(49.3%) of respondents ranked Warthog (Phacochoerus africanus) as primary crop raider. Whilst majority of the respondents 115(82.1%) perceived Maize was frequently and severely damaged cereal crop. Most 80 (57.1%) respondents used different methods simultaneously to minimize damage caused by wild animals. Nearly half, (48.6%) of respondents had negative and strong negative attitude towards wildlife conservation. Level of education and amount of money imposed as penalty for illegal grazing were the most important factors affecting the local community attitudes towards wildlife conservation. Improve livestock husbandry, use appropriate guarding methods, education and make the community the actor of conservation would be vital to enhance the peaceful co-existence between human and wildlife in the study area.
Grassland systems constitute a significant portion of the land area in the U.S., and as a result, harbor a significant amount of arthropod diversity. During this time of biodiversity loss around the world, bioinventories of ecologically important habitats serve as important indicators for the effectiveness of conservation efforts. We conducted a bioinventory of the foliar, soil, and dung arthropod communities in 10 cattle pastures located in the southeastern U.S. during the 2018 grazing season. In sum, 126,251 specimens were collected. From the foliar community, 13 arthropod orders were observed, with the greatest species richness found in Hymenoptera, Diptera, and Hemiptera. The soil-dwelling arthropod community contained 18 orders. The three orders comprising the highest species richness were Coleoptera, Diptera, and Hymenoptera. Lastly, 12 arthropod orders were collected from cattle dung, with the greatest species richness found in Coleoptera, Diptera, and Hymenoptera. Herbivores were the most abundant functional guild found in the foliar community, and predators were most abundant in the soil and dung communities. While bioinventories demand considerable time, energy, and resources to accomplish, the information from these inventories has many uses for conservation efforts, land management recommendations, and the direction of climate change science.
The Intermediate Disturbance Hypothesis is widely considered to be wrong but is rarely tested against alternative hypotheses. It predicts that soil disturbances and herbivory have identical impacts on species richness via identical mechanisms (reduction in biomass and in competition). An alternative hypothesis is that the specific traits of disturbance agents (small mammals) and plants differentially affects richness or abundance of different plant groups. We tested these hypotheses on a degu (Octodon degus) colony in central Chile. We ask whether native and non-native forbs respond differently to degu bioturbation on runways vs. herbivory on grazing lawns. We ask whether this can explain the increase in non-native plants on degu colonies. We found that biopedturbation did not explain the locations of non-native plants. We did not find direct evidence of grazing increasing non-native herbs either, but a grazing effect appears to be mediated by grass, which is the dominant cover. Further, we provide supplementary evidence to support our interpretation that a key mechanism of non-native spread is the formation of dry soil conditions on grazing lawns. Thus ecosystem engineering (alteration of soil qualities) may be an outcome of disturbances, which each interact with specific plant traits, to create the observed pattern of non-native spread in the colony. Based on these results we propose to extend Jentsch & White’s (2019) concept of combined pulse/ disturbance events to the long-term process duality of ecosystem engineering/ disturbance.
Aim: Invasive alien species (IAS) threaten ecosystems and humans worldwide, and future climate change may accelerate the expansion of IAS. Predicting the suitable distributions of IAS can prevent their further expansion. Ageratina adenophora is a invasive weed over 30 countries in tropical and subtropical regions. However, the potential suitable distribution of A. adenophora remains unclear along with its response to climate change. This study explored and mapped the current and future potential distributions of Ageratina adenophora. Location: Global Taxa: Asteraceae A. adenophora (Spreng.) R.M.King & H.Rob. Commonly known as Crofton weed. Methods: Based on A. adenophora occurrence data and climate data, we predicted its potential distribution of this weed under current and future (four RCPs in 2050 and 2070) by MaxEnt model. We used ArcGIS 10.4 to explore the distribution characteristics of this weed and the ‘ecospat’ package in R to analyse its altitudinal distribution changes. Results: The area under the curve value (>0.9) indicated excelled model performance. Among environment factors, Mean Temperature of Coldest Quarter contributed most to the model. Globally, the suitable habitat for A.adenophora invasion decreased under climate change scenarios, although regional increase were observed, including in six biodiversity hotspot regions. The potential suitable habitat of A.adenophora under climate change moved toward regions with higher elevation. Main Conclusions: Temperature was the most important variable influencing the distribution of A. Adenophora. Under the background of warming climate, the potential distribution range of A.adenophora will shrink globally but increase regionally. The distribution of A.adenophora will shift toward higher elevation under climate change. Mountain ecosystems are of special concern as they are rich in biodiversity and sensitive to climate change, and increasing human activities provide more opportunities for IAS invasion.
The effects of human disturbance on the stability of alpine meadow communities, their diversity–stability relationship, and the underlying mechanisms are still not fully understood. Here, we performed a 12-year-long (2007–2018) two-factor (2 × 3) controlled experiment on Kobresia humilis on the Tibetan Plateau. The manipulations included three clipping levels (no clipping, NC; moderate clipping, MC; heavy clipping, HC) and two fertilization levels (no fertilization, NF; fertilization, F). Our results revealed that the two clipping manipulations significantly increased the temporal stability of alpine meadow communities, whose significant increase was more pronounced under the MC than HC treatment. Moreover, asynchrony effects, portfolio effects, and facilitation interactions were all present in the communities under the six types of experimental treatment combinations. Additionally, a selection effect was detected in the compound communities, demonstrating characteristics that are common to different mechanisms. There were no significant differences in the effects of these mechanisms on community temporal stability between the NC–NF and MC–NF interactive communities. The portfolio effects predominated when clipping intensity was moderate under both fertilization and non-fertilization conditions. By contrast, in the compound communities, the selection effect predominated. In summary, we conclude that in meadow communities that undergo clipping and fertilization disturbances, facilitation interactions and weak interactions make a greater contribution toward maintaining their temporal stability.
We aimed to infer the phylogenetic relationships of populations of Lobelia columnaris using chloroplast genomes and estimate the divergence time to reconstruct its historical colonization on the sky islands of Bioko and Cameroon. Specifically, we aim to answer the following questions: (1) What is the phylogenetic relationship among Bioko Island and Cameroon populations? (2) Are the older populations found on the older sky islands? (3) Does the colonization history reflect the age of the sky islands? We assembled novel plastomes from 20 individuals of L. columnaris from five mountain systems. The plastome data was explored with phylogenetic analyses using Maximum likelihood and Bayesian Inference. The complete plastome size varied from 164,609 bp to 165,368 bp. The populations of L. columnaris have a monophyletic origin, subdivided into three plastome-geographic clades. The plastid phylogenomic results and age of the sky islands indicate that L. columnaris colonized first along the Cameroon Volcanic Line’s young sky islands. The earliest divergent event (1.54 Ma) split the population in South Bioko from those on the mainland and North Bioko. The population of South Bioko was likely isolated during cold and dry conditions in forest refugia. Presumably, the colonization history occurred during the middle-late Pleistocene from South Bioko’s young sky island to North Bioko and the northern old sky islands in Cameroon. Furthermore, the central depression with lowland forest between North and South Bioko is a current geographic barrier that keeps separate the populations of Bioko from each other and the mainland populations. The Pleistocene climatic oscillations led to the divergence of the Cameroon and Bioko populations into three clades. L. columnaris colonized the older sky island in mainland Cameroon after establishing South Bioko’s younger sky islands. The biogeography history was an inverse progression concerning the age of the Afromontane sky islands.
In spring of 2012, we studied the feeding habits of snow leopard using a comprehensive approach that combines fecal genetic sampling, macro and microscopic analysis of snow leopard diets and direct observation of Naur and livestock in Kangchenjunga Conservation Area of east Nepal. Out of collected 88 putative snow leopard scat samples from 140 transects (290 km) in 27 (4*4 km2) sampling grid cells, 83% were confirmed to be from snow leopard. The genetic analysis accounted for 19 individual snow leopards (10 male and 9 female) with a mean population size estimate of 24 (95% CI: 19- 29), and an average density of 3.9 snow leopards/100 km2 within 609 km2. Total available prey biomass of Naur and Yak was estimated at 355,236 kg (505 kg yak/km2 and 78 kg Naur/km2). From the available prey biomass, we estimated snow leopards consumed 7% annually which was comprised of wild prey (49%), domestic livestock (45%), and 6% unidentified items. The estimated 47,736 kg Naur biomass gives a snow leopard-Naur ratio of 1: 59 on a weight basis. The proportion of young Naur was estimated at 17%, with an almost double predation rate at 28%. Predators such as common leopard and wolf share the same habitat and might compete with snow leopard for prey which will likely influence future predator-prey associations in KCA. Along with livestock insurance scheme improvement, there needs to be a focus on improved livestock guarding as well as engaging and educating local people to be citizen scientists on the importance of snow leopard conservation, involving them in long-term monitoring programs and promotion of ecotourism.
1. Phyllostomid bats exhibit great diversity in skull size and morphology that reflects the degree of resource division and ecological overlap in the group. In particular, Stenodermatinae has high morphological diversification associated with cranial and mandibular traits that is associated with the ability to consume the full range of available fruits (soft and hard). In terms of morphology, performance (bite force) appears to play an important role in niche partitioning among bat species, however, very few studies have confirmed these relationships using functional cranial traits. 2. Here, we analyzed craniodental traits and their relationship to the bite force in 308 specimens distributed in seven species of stenodermatine bats with two foraging types: nomadic and sedentary frugivorous bats. We evaluated 19 functional traits of the skull and jaw related to feeding and bite force in live animals by correcting bite force with body size. We used a GLM model and post hoc tests to determine possible relationships and differences between cranial traits, species, and sex. 3. The results showed that there is significant interspecific variation between stenodermatines that are nomadic and sedentary. The greatest variation in bite force within species was explained by the mandibular toothrow length (MANDL) between sexes, which was greater in females. The larger species of Artibeus, together with Platyrrhinus helleri, Uroderma convexum and Sturnira giannae, which have a greater length of the skull, condylo-incisor, condylo-canine, mandibular toothrow and height of the coronoid, exhibit greater bite force. By contrast, the smaller species A. anderseni and A. phaeotis have short skulls and the lowest values of bite force, which suggests that the size of the skull confers a biomechanical advantage. 4. Our results highlight the usefulness of analyzing functional traits related to feeding to establish the performance of bats in terms of the bite force.
Beneficial mutations can become costly following an environmental change. Compensatory mutations can relieve these costs, while not affecting the selected function, so that the benefits are retained if the environment shifts back to be similar to the one in which the beneficial mutation was originally selected. Compensatory mutations have been extensively studied in the context of antibiotic resistance, responses to specific genetic perturbations and in the determination of interacting gene network components. Few studies have focused on the role of compensatory mutations during more general adaptation, especially as the result of selection in fluctuating environments where adaptations to different environment components may often involve tradeoffs. We examine if costs of a mutation in lacI, which deregulated expression of the lac operon in evolving populations of Escherichia coli bacteria, was compensated. This mutation occurred in multiple replicate populations selected in environments that fluctuated between growth on lactose, where the mutation was beneficial, and on glucose, where it was deleterious. We found that compensation for the cost of the lacI mutation was rare, but, when it did occur, it did not negatively affect the selected benefit. Compensation was not more likely to occur in a particular evolution environment. Compensation has the potential to remove pleiotropic costs of adaptation, but its rarity indicates that the circumstances to bring about the phenomenon may be peculiar to each individual or impeded by other selected mutations.
In semi-arid environments, aperiodic rainfall pulses determine cycles of plant production and resource availability for higher trophic levels, creating strong bottom-up regulation. The influence of climatic factors on population vital rates often shapes the dynamics of small mammal populations in such resource-restricted environments. Using a 21-year biannual capture–recapture dataset (1993 to 2014), we examined the impacts of climatic factors on the population dynamics of the brush mouse (Peromyscus boylii) in semi-arid oak woodland of coastal-central California. We applied Pradel’s temporal symmetry model to estimate capture probability (p), apparent survival (φ), recruitment (f), and realized population growth rate (λ) of the brush mouse, and examined the effects of temperature, rainfall, and El Niño on these demographic parameters. The population was stable during the study period with a monthly realized population growth rate of 0.993 ± SE 0.032, but growth varied over time from 0.680 ± 0.054 to 1.450 ± 0.083. Monthly survival estimates averaged 0.817 ± 0.005 and monthly recruitment estimates averaged 0.175 ± 0.038. Survival probability and realized population growth were positively correlated with rainfall and negatively correlated with temperature. In contrast, recruitment was negatively correlated with rainfall and positively correlated with temperature. Brush mice maintained their population through multiple coping strategies, investing in high recruitment during warmer and drier periods and allocating more energy towards survival during cooler and wetter conditions. Although climatic change in coastal-central California will favor recruitment over survival, varying strategies may serve as a mechanism by which brush mice maintain resilience in the face of climate change. Our results indicate that rainfall and temperature are both important drivers of brush mouse population dynamics and will play a significant role in predicting the future viability of brush mice under a changing climate.
Understanding the genetic properties of adaptive trait evolution is a fundamental crux of biological inquiry that links molecular processes to biological diversity. Important uncertainties persist regarding the genetic predictability of adaptive trait change, the role of standing variation, and whether adaptation tends to result in the fixation of favored variants. Here, we use the recurrent evolution of enhanced ethanol resistance in Drosophila melanogaster during this species' worldwide expansion as a promising system to add to our understanding of the genetics of adaptation. We find that elevated ethanol resistance has evolved at least three times in different cooler regions of the species' modern range - not only at high latitude but also in two African high altitude regions - and that ethanol and cold resistance may have a partially shared genetic basis. Applying a bulk segregant mapping framework, we find that the genetic architecture of ethanol resistance evolution differs substantially not only between our three resistant populations, but also between two crosses involving the same European population. We then apply population genetic scans for local adaptation within our quantitative trait locus regions, and we find potential contributions of genes with annotated roles in spindle localization, membrane composition, sterol and alcohol metabolism, and other processes. We also apply simulation-based analyses that confirm the variable genetic basis of ethanol resistance and hint at a moderately polygenic architecture. However, these simulations indicate that larger-scale studies will be needed to more clearly quantify the genetic architecture of adaptive evolution, and to firmly connect trait evolution to specific causative loci.
To study the effect of the invasion of Bursaphelenchus xylophilus on the functional relationship between woody plants and insect communities, the populations of tree species and insect communities were investigative in the Masson pine forests with different infestation durations of B. xylophilus. In this study, the number of Pinus massoniana began to decrease sharply, whereas the total number of other tree species in the arboreal layer increased gradually with the infestation duration of B. xylophilus. The principal component analysis ordination biplot shows that there was a significant change in the spatial distribution of woody plant species in different Masson pine forest stands. Additionally, a total of 7,188 insect specimens was obtained. The insect population showed an upward trend in stand types with the increase of pine wilt disease infection periods, which demonstrated that the insect community had been significantly affected by the invasion of B. xylophilus. The structure of insect functional groups changed from herbivorous (He) > omnivorous (Om) > predatory (Pr) > parasitic (Pa) > detritivorous (De) in the control stand to He > Pa > Om, De > Pr after B. xylophilus infestation in the forests. The results showed that the populations of He, Pa, and De increased after the invasion of B. xylophilus, but the populations of Pr decreased. Moreover, the redundancy analysis ordination bi-plots reflected the complicated functional relationship between woody plant communities and insects after the invasion of B. xylophilus. The present study provides insights into the changes in the community structure of woody plants and insects, as well as the functional relationship between woody plant communities and insect communities after invasion of B. xylophilus.