Due to the urbanization and human invasion of the natural environments, a great deal of changes have occurred on the food composition and feeding ecology of several animals especially those are sharing humans their habitats in fields, wadis and gardens. The Desert Hedgehogs Paraechinus aethiopicus populations inhabiting different localities in Saudi Arabia were studied by using stomach contents analysis between February 2015 and October 2019. Precise analysis of 55 stomach contents of hedgehogs showed that the food of The Desert Hedgehogs Paraechinus aethiopicus is highly diverse and highly influenced with effect of humans on the environment includes cooked rice, insects, plant materials, egg shells, worms, garbage and remains of mammals and birds. Diet composition showed seasonal variations that are apparently associated with changes in the availability of different food items. The present results clearly showed that The Desert Hedgehogs Paraechinus aethiopicus is a generalist animal, capable of adapting to a great variety of dietary compositions in the study sites.

Secondary contact between closely related species can lead to the formation of hybrid zones, allowing for interspecific gene flow among taxa. Species replacement can take place if one of the species possesses a competitive advantage over the other, resulting in hybrid zone movement. This displacement may leave a genomic footprint across the landscape in the form of asymmetric introgression of selectively neutral alleles from the displaced to the advancing species. Hybrid zone movement has been suggested for marbled newts in the Iberian Peninsula, supported by the presence of a Triturus marmoratus stronghold surrounded by populations of the supposedly advancing T. pygmaeus in the northwest of the Lisbon Peninsula, i.e., an enclave. Moreover, a newly constructed two-species distribution model suggests that climate conditions following the Last Glacial Maximum may have favoured T. pygmaeus over T. marmoratus along the Atlantic coast. To test for the presence of a T. marmoratus genomic footprint in the area that may have witnessed species displacement, we developed and employed 54 nuclear SNPs and one mitochondrial DNA marker. We found no additional enclaves nor genetic traces of T. marmoratus in T. pygmaeus populations. Therefore, two main hypothesis arise in the absence of a genomic footprint: i) species replacement without hybridisation, either in allopatry or in sympatry under strong reproductive isolation; or ii) displacement with hybridisation where the footprint was eroded due to strong purifying selection. We predict testing for a genomic footprint north of the reported enclave could confirm that species replacement in the marbled newts occurred with hybridisation.

Temporal partitioning is an important mechanism for carnivore mammals that live in sympatry in current forest remnants. We evaluated whether temporal partitioning would facilitate coexistence among carnivores in a tropical forest and its adjacent human-related area, as well as if there is a possible correlation between the activity patterns of these carnivores and their potential prey. We used camera traps and circular statistics to explore the degree of temporal overlap between dominant and subordinate predators, as well as between predators and their potential preys. Pumas (Puma concolor) were less active when jaguars (Panthera onca) were more active. Overall, ocelots (Leopardus pardalis) and crab-eating foxes (Cerdocyon thous) presented either a strong or a weak temporal partitioning with jaguars and pumas, respectively, but apparently spatial or dietary segregation might facilitate more their coexistence with these large predators. Tayras (Eira barbara) and coatis (Nasua nasua) were diurnal and, therefore, did not overlap temporally with nocturnal carnivores, except pumas. In the human-related area, ocelots were mostly nocturnal and pumas diurnal, probably due to the temporal activity of their related preys. Our findings suggest that temporal partitioning may allow coexistence between our studied predators in one of the largest Atlantic Forest remnant in Brazil, but preys have an important role, shifting the activity pattern of their predators according to the studied area.

Small mammal abundances are frequently limited by resource availability but predators can exert strong lethal (direct mortality) and non-lethal limitations (e.g. depressed site-level activity). Artificially increasing resource availability for small mammals provides a unique opportunity to examine predator-prey interactions. We monitored the 3-year response of arboreal rodents and their predators at nest platforms (n = 598; 23 young forest sites), using annual inspections and remote cameras (n = 168). One year after adding nest platforms we found a 2.9 to 9.2-fold increase in red tree vole (Arborimus longicaudus) use at the site-level, but little use by potential predators. Predator use of nest platforms began in year two and increased in year three of the study. Most potential nest predators were positively correlated with tree vole presence at nest platforms but effect size and direction varied with temporal grain considered (e.g. hour vs day time-bin widths). Flying squirrels (Glaucomys humboldtensis) were positively correlated with disturbances caused by digging birds. Using a Cormack-Jolly-Seber model and encounter histories produced from visual re-captures of marked tree voles, we estimated apparent annual survival to be 0.099 ± 0.057 (x̄ ± 1 SE) for females and 0.005 ± 0.014 for males. Weasels (Mustela spp.), an active seeking predator, preyed upon tree voles most frequently with 10% of weasel detections resulting in mortality of a tree vole (n = 8) whereas owls, an ambush predator, did not prey upon tree voles at nest platforms even though they were detected at similar frequencies as weasels. Weasels also exerted potential non-lethal effects and we observed a >10-fold reduction in the number of tree vole detections per week after weasel detection. Our evidence indicates that predators exert direct and indirect effects on tree vole populations with active seeking predators being the most important predators at nest sites.

1. Plant leaf stomata are the gatekeepers of the atmosphere-plant interface and are essential building blocks of land surface models as they control transpiration and photosynthesis. Although more stomatal trait data is needed to significantly reduce the error in these model predictions, recording these traits is time-consuming and no standardized protocol is currently available. Some attempts were made to automate stomatal detection from photomicrographs, however, these approaches have the disadvantage of using classic image processing or targeting a narrow taxonomic entity which makes these technologies less robust and generalizable to other plant species. We propose an easy-to-use and adaptable workflow from leaf to label. A methodology for automatic stomata detection was developed using deep neural networks according to the state-of-the-art and its applicability demonstrated across the phylogeny of the angiosperms. 2. We used a patch-based approach for training/tuning three different deep learning architectures. For training, we used 431 micrographs taken from leaf prints made according the nail polish method from herbarium specimens of 19 species. The best performing architecture was tested on 595 images of 16 additional species spread across the angiosperm phylogeny. 3. The nail polish method was successfully applied in 78% of the species sampled here. The VGG19 architecture slightly outperformed the basic shallow and deep architectures, with a confidence threshold equal to 0.7 resulting in an optimal trade-off between precision and recall. Applying this threshold the VGG19 architecture obtained an average F-score of 0.87, 0.89 and 0.67 on the training, validation and unseen test set, respectively. The average accuracy was very high (94%) for computed stomatal counts on unseen images of species used for training. 4. The leaf-to-label pipeline is an easy-to-use workflow for researchers of different areas of expertise interested in detecting stomata more efficiently. The described methodology was based on multiple species and well-established methods so that it can serve as a reference for future work.

1. Gummosis on Acacia decurrens, an invasive tree species, that got established in Merapi Volcano National Park (MVNP) after the eruption of Mount Merapi in 2010 was studied to i) identify the causal organism of the disease, ii) analyze disease symptoms, iii) understand the spatio-temporal distribution of gummosis in the tree population and iv) examine how the disease affects the anatomy of tree wood. 2. Pathological, morphological and molecular studies were used in this studies. 3. Ceratocystis fimbriata was proved to be the causal organism of the disease. The disease spread was probably aided by the ambrosia beetle (Euwallacea sp.) which bores holes on the stem. 4. The disease is noted to spread from the base of the trees, where the ambrosia beetle bores holes first, to the upper part. 5. The number of parenchyma cells in the infected stem was significantly more than in the healthy stem which apparently facilitated water and nutrition transport within the tree helping it to grow normally despite serious gummosis. 6. The management of invasion by A. decurrens in the MVNP area poses a serious challenge due its success as an invader in the volcano impacted area and the threat of the gummosis pathogen spreading to other species both of which will affect the regeneration and establishment of native species and recuperation of the ecosystem.

Fungi are a key component of tropical biodiversity. Due to their inconspicuous and largely subterranean nature, they are however usually neglected in biodiversity inventories. The goal of this study was to identify the key determinants of fungal richness, community composition, and turnover in tropical rainforests. We tested specifically for the effect of soil properties, habitat, and locality in Amazonia. For these analyses, we used high-throughput sequencing data of short and long reads of fungal DNA present in soil and organic litter samples, combining existing and novel genomic data. Habitat type (phytophysiognomies) emerges as the strongest factor in explaining fungal community composition. Naturally open areas – campinas – are the richest habitat overall. Soil properties have different effects depending on the soil layer (litter or mineral soil) and the choice of genetic marker. We suggest that campinas could be a neglected hotspot of fungal diversity. An underlying cause for their rich diversity may be the overall low soil fertility, which increases the reliance on biotic interactions essential for nutrient absorption in these environments, notably ectomycorrhizal fungi–plant associations. Our results highlight the advantages of using both short and long DNA reads produced through high-throughput sequencing to characterize fungal diversity. While short-reads can suffice for diversity and community comparison, long-reads add taxonomic precision and have the potential to reveal population diversity.

1. The abundance of UV-B absorbing compounds (for example p-Coumaric acid, pCA) within pollen-grain sporopollenin has been proposed as a proxy for reconstructing past changes in surface solar radiation, but drivers of the variation of these compounds in pollen grains remains poorly understood. 2. One important consideration is that the physiological response that results in the production and timing of pCA in pollen remains poorly understood. This calls for studies that explicitly tests the temporal resolution and plasticity of the response of pCA in pollen under field conditions. 3. To address this, we conducted two parallel experiments. First, we measured pCA in four Pinus spp. from Geneva in two consecutive years to investigate the impact of natural variation in ambient solar radiation, and differences in responses between species. Second, we covered pollen cones on Pinus sylvestris trees in Bergen with 90% shading cloth one month before dehiscence and compared the amount of pCA in pollen from shaded and sun-exposed cones from the same tree. 4. Between years, in Geneva, Pinus spp. produced 31% more pCA in 2014 than in 2013, with higher levels of solar radiation also observed in 2014. pCA content also showed strong species-level variation, largely reflecting differences in pollen size between species. Experimentally shaded Pinus sylvestris pollen produced 21% less pCA than fully exposed pollen. 5. Our work demonstrates a plastic response in the production of UV absorbing compounds (pCA) to inter-annual and experimentally induced variation in ambient solar radiation in Pinus spp. pollen. This supports pCA as a highly responsive proxy for early-season solar radiation. We also find strong species-level variation in pCA content in pine pollen, likely related to pollen grain size, which should be accounted for in reconstructions from sites with multiple Pinus species present.

The complex and enormous diversity of microbiome associated with plant roots is important for plant health and is shaped by numerous factors. This study aimed to unravel the effects of a pesticide-fertilizer combination on the rhizosphere microbiome of field-grown sugarcane. A field trial on sugarcane was conducted in Zhanjian city, Guangdong Province of China, and bulk soil and rhizosphere samples were collected 3 weeks after planting. We examined the effects of clothianidin and/or organic fertilizer treatments on the composition, diversity, and function of rhizosphere microbial communities using 16S rRNA gene and ITS1 gene amplicon sequencing. Compared with the controls (no pesticide or fertilizer used), the microbial community that resulted from treating with the pesticide-fertilizer (SPF) had a higher relative bacterial diversity and abundance, as well as contributing more comprehensive functions to sugarcane. The bacterial and fungal compositions at different taxonomic levels affected by clothianidin in the SPF and SP (with pesticide addition) were different from the effects experienced in the other treatments. With organic fertilizers added to SPF, the abundance of soil beneficial bacteria Bacillus, Paenibacillus, and Brevibacillus were highly improved, as well as the microbial function. It indicated that the SPF treatment could counteract the effects caused by mixing with clothianidin when compared to the SP treatment with only pesticide addition. Moreover, four bacterial genera including Dyella, Sphingomonas, Catenulispora, Mucilaginibacter, and Tumebacillus were significantly increased in the SPF and SP groups, which was reported to degrade clothianidin and could improve the soil health. The findings of the study provide insights into the interaction between the rhizosphere soil microbiome and a pesticide-fertilizer integration that may help improve application for pesticide-fertilizer in sugarcane fields.

The European honey bee (Apis mellifera) is both a crucial pollinator for agricultural and natural ecosystems, and an agricultural commodity in its own right. However, honey bees are experiencing heavy mortality in North America and Europe due to a complex suite of factors. Weather affects both the bees themselves and the plants that support them. Surrounding land use, particularly proportion of agricultural and urban areas, determines forage resource abundance and pesticide exposure risk. Finally, management decisions, including treatment to control parasitic Varroa destructor mites, contribute to colony success and failure. We used three years of data from a survey of Pennsylvania beekeepers to assess the importance of weather, topography, land use, and management factors on overwintering mortality of managed honey bee colonies at both apiary and colony levels. A Random Forest model for mite-treated apiaries predicted overwintering survival with 73.3% accuracy for colonies and 65.7% for apiaries, as determined by cross-validation. Growing degree days was the most important predictor at both levels. Neither topographic nor management variables were important predictors. A weather-only model was used to predict colony survival probability across Pennsylvania for the three years of the study, and to create a composite map of survival probability for 1981-2019 (long-term probability mean value of 59.5%). Although three years of data were not enough to adequately capture the range of possible climatic conditions, the model nonetheless performed well within its constraints. The Random Forest approach is suited to understanding complex nonlinear drivers of survival, and to predicting outcomes given current conditions or projected climate changes.

Population dynamics models combine density-dependence and environmental effects. Ignoring sampling uncertainty might lead to biased estimation of the strength of density-dependence. This is typically addressed using state-space model approaches, which integrate sampling error and population process estimates. Such models seldom include an explicit link between the sampling procedures and the true abundance, which is common in capture-recapture settings. However, many of the models proposed to estimate abundance in the presence of heterogeneity lead to incomplete likelihood functions and cannot be straightforwardly included in state-space models. We assessed the importance of estimating sampling error explicitly by taking an intermediate approach between ignoring uncertainty in abundance estimates and fully specified state-space models for density-dependence estimation based on autoregressive processes. First, we estimated individual capture probabilities based on a heterogeneity model, using a conditional multinomial likelihood, followed by a Horvitz-Thompson estimate for abundance. Second, we estimated coefficients of autoregressive models for the log abundance. Inference was performed using the methodology of integrated nested Laplace approximation (INLA). We performed an extensive simulation study to compare our approach with estimates disregarding capture history information, and using R-package VGAM, for different parameter specifications. The methods were then applied to a real dataset of gray-sided voles Myodes rufocanus from Northern Norway. We found that density-dependence estimation was improved when explicitly modelling sampling error in scenarios with low innovation variances, in which differences in coverage reached up to 8% in estimating the coefficients of the autoregressive processes. In this case, the bias also increased assuming a Poisson distribution in the observational model. For high innovation variances, the differences between methods were small and it appeared less important to model heterogeneity.

1. The reduction of plant diversity following eutrophication threatens many ecosystems worldwide. Yet, the mechanisms by which species are lost following nutrient enrichment are still not completely understood, nor are the details of when such mechanisms act during the growing season, which hampers understanding and the development of mitigation strategies. 2. Using a common garden competition experiment, we found that early-season differences in growth rates among five perennial grass species measured in monoculture predicted short-term competitive dominance in pairwise combinations and that this effect was stronger under a fertilisation treatment. 3. We also examined the role of early-season growth rate in determining the outcome of competition along an experimental nutrient gradient in an alpine meadow. Early differences in growth rate between species predicted short-term competitive dominance under both ambient and fertilized conditions and competitive exclusion under fertilized conditions. 4. The results of these two studies suggests that plant species growing faster during the early stage of the growing season gain a competitive advantage over species that initially grow more slowly, and that this advantage is magnified under fertilisation. This finding is consistent with the theory of asymmetric competition for light in which fast-growing species can intercept incident light and hence outcompete and exclude slower-growing (and hence shorter) species. We predict that the current chronic nutrient inputs into many terrestrial ecosystems worldwide will reduce plant diversity and maintain low biodiversity state by continuously favouring fast-growing species. Biodiversity management strategies should focus on controlling nutrient inputs and reducing the growth of fast-growing species early in the season.

Plant negative density dependence is the result of interactions between plants themselves and between plants and the environment. We selected a succession series comprising early successional, mid-successional and late successional stages (Artemisia ordosica, Sophora alopecuroides and Stipa bungeana communities, respectively) in a semi-arid area. We investigated plant density and biomass and determined the nitrogen (N) and phosphorus (P) contents of each plant species in each of 225 quadrats, and we calculated the N and P contents of vegetation using biomass as a weighted coefficient. We found that the total plant density of the A. ordosica community increased with the increase in vegetation N:P ratio while the total plant density of the S. bungeana community decreased with the increase in vegetation N:P ratio, with the latter (late successional stage) community exhibiting negative density dependence. In the communities representing the early successional and mid-successional stages, the vertex coordinate of the quadratic function relationship between plant total density and vegetation N/P ratio was (16.6, 353.3); that is, if the N:P ratio of the vegetation was greater than 16.6, the community was characterized by negative density dependence. The analysis showed that the negative density dependence was due to P limitation. These findings reveal that the vegetation N:P ratio in a semi-arid region is the driver of negative density dependence.

The biogeographical distribution of diversity among populations of threatened mammalian species is generally investigated through population genetics. However, intraspecific phenotypic diversity is rarely assessed beyond taxonomy-focused linear measurements or qualitative descriptions. Here, we use a technique widely used in the evolutionary sciences – geometric morphometrics – to characterize shape diversity in the skull of an endangered marsupial, the northern quoll, across its 5,000 km distribution range along the northern Australian coast. Skull shape is a proxy of feeding, behaviour, and phenotypic differentiation, allowing us to ask if populations can be distinguished and if patterns of variation indicate adaptability to changing environmental conditions. We analysed skull shape in 101 individuals across the four mainland populations and several islands. We assessed the contribution of population, size, sex, rainfall, temperature, and latitude/longitude to skull shape variation through Principal Components, Procrustes ANOVA, and variation partitioning analyses. Regardless of land area inhabited, northern quoll populations harbour similar amounts of broadly overlapping skull shape variation. Size predicted skull shape best, coinciding with braincase size variation and differences in the cheekbone shape. Size-adjusted population differences explained less variation with far smaller effect sizes, relating to changes in insertion areas of masticatory muscles, as well as the upper muzzle and incisor region. Climatic and geographic variables contributed little or nothing. Strikingly, the vast majority of shape variation - 76% - remained unexplained. Our results suggest a uniform within-species scope for shape variation, possibly due to phenotypic plasticity or allometric constraints. The lack of local adaptation indicates that cross-breeding between populations will not reduce local morphological skull (and probably general musculoskeletal) adaptation because none exists. However, the potential for heritable morphological variation (e.g. specialization to local diets) seems exceedingly limited. We conclude that 3D geometric morphometrics can provide a comprehensive, statistically rigorous phenomic contribution to genetics-based conservation studies.

The shifting defence hypothesis attributes the invasion success of many plant species to the species’ post- introduction evolution of traits that confer high fitness including reduced allocation to physiologically and ecologically costly chemical defence compounds against herbivores. However, to date, most of the studies that compared invasive and conspecific native plants for differences in defence compounds focused only on one or a few compounds. Thus, it remains unclear whether invasive plants may evolve a lower diversity of defence compounds in response to a simplified herbivore community assemblages in the introduced range. Therefore, the present study used B. nigra plants from 11 invasive- and 14 native range populations to test whether invasive B. nigra plants: i) express a lower diversity of glucosinolate compounds and higher concentration of a single dominant glucosinolate compound owing to a reduced diversity of herbivores in the introduced range; ii) are less preferred by generalist herbivores and attract more specialist herbivore species than B. nigra from the native range when grown in a common garden in the native range; iii) are less preferred by generalist herbivores than native-range B. nigra in no- choice feeding bioassays. In support of the shifting defence hypothesis, invasive B. nigra plants expressed a lower diversity of glucosinolates and a higher concentration of sinigrin (a major glucosinolate compound in B. nigra) than native-range B. nigra plants. Moreover, the invasive B. nigra plants were more deterrent to two generalist herbivore species in no-choice feeding bioassays than native B. nigra plants. Brassica nigra plants that expressed higher concentrations and diversities of glucosinolate compounds were visited by a more diverse specialist herbivore community than B. nigra plants with low concentrations and diversities of glucosinolates. The biogeographical differences in glucosinolate profiles observed here may be the result of differential herbivore selection pressures in the respective invaded and native ranges.

The Sanjiang Plain is the biggest freshwater wetland locating within northeastern China. Due to climate change and human activities, that wetland has degraded to a successional gradient from the original flooded wetland to dry shrub vegetation and a forest area with lower ground water level, resulting in changes in soil microbiologic structure and functions. The present study investigated the microbial diversity and community structure in relation to soil properties along this gradient. The soil physic-chemical properties changed significantly with degradation. The Shannon variety of soil fungi as well as bacteria varied significantly with successional stage (both P < 0.05). The community structures of soil bacteria and fungi in the early successional stages (i.e., the wetland) were significantly structured via total phosphorus, available nitrogen and total nitrogen concentrations in soils, while those in the later successional stages (i.e., forests) were significantly structured by soil organic carbon, soil pH and available phosphorus concentrations. Our results indicated that variations in the soil environment affected soil microbial communities along a successional gradient from wetland to forests are mainly. These outcomes indicate that above ground plant composition is a forceful determinant of the structure as well as functions of bacterial and fungal communities, might finally causing substantial alterations in ecosystem activity.

Many eusocial insects, including ants, show complex colony structures, distributions, and reproductive strategies. In the ant Vollenhovia emeryi Wheeler (Hymenoptera: Myrmicinae), queens and males are produced clonally, while sterile workers arise sexually, unlike other ant species and Hymenopteran insects in general. Furthermore, there is a wing length polymorphism in the queen caste. Despite its ecological and evolutionary importance, little is known about the population dynamics and structure of this ant species, which may provide insight into its unique reproductive mode and polymorphic traits. We performed in-depth analyses of ant populations from Korea, Japan, and North America using three mitochondrial genes (COI, COII, and Cytb). The long-winged (L) morph is predominant in Korean populations, and the short-winged (S) morph is very rare. Interestingly, all L morphs were infected with Wolbachia, while all Korean S morphs lacked Wolbachia, demonstrating a novel association between a symbiont and a phenotypic trait. A phylogenetic analysis revealed that the S morph is derived from the L morph. We propose that the S morph is associated with potential resistance to Wolbachia infection, and that Wolbachia infection does not influence clonal reproduction.

Maize and teosintes are excellent systems for study of population and ecological genomics, as well as teosintes provide excellent germplasm resources for forage maize breeding. However, genetic relationship, evolution, hybridization and introgression among the genus Zea species have not been completely resolved and effective methods for Zea species classification and identification are scarce. In current study, nuclear (ITS), mitochondrial DNA (atp6, cob and nad1) and chloroplast DNA sequences (matK, psbA-trnH and rbcL) were used to explore as a simple and efficient DNA barcode for identification and genetic study of the Zea species. Phylogenetic incongruence between nuclear and cytoplasmic sequences detected in present study. The lowest divergence value from pairwise comparisons were found between Z. mexicana and Z. parviglumis based on combined six cytoplasmic sequences and Z. mexicana and maize showed lowest divergence value based on ITS sequences. It is suggested that single-gene data sets and combined data sets of six cytoplasmic sequences failed to identify and classify every species at inter-species level, however, the combined data set containing ITS and atp6 can identify and classify Zea species perfectly. Moreover, the tetraploid Z. perennis was confirmed an autotetraploid of diploid Z. diploperennis reflecting from phylogenetic tree based on combined six cytoplasmic sequences.

Objective: Climate change coupled with anthropogenic events can alter the distribution of biological groups and affect the reorganization, structure, dynamics and functioning of ecosystems and their services. Despite this, predictions of impacts on Brazilian savannas are scarce. This study estimated the potential effects of climate change on peripheral plant diversity by predicting the distribution of species from Cerrado. Site: Northern Brazilian Cerrado (NBC). Methods: Ecological niche modeling was used to provide present and future projections of responses in terms of occurrence of ten woody species based on four algorithms and four future climate change scenarios for the year 2050. Potential refuge areas for conservation actions were identified, and evidence of the vulnerability of the flora was demonstrated based on the disparity between potential areas of climate stability amid current protected areas (Conservation Units - CUs). Results: The results suggested a lack of pattern between the scenarios and an idiosyncratic response of the species, indicating different impacts on plant communities and the existence of unequal stable alternative conditions, which could bring consequences to the ecological relationships and functionality of the floras. Even in the most pessimistic scenarios, most species presented an expansion of potential occurrence areas, suppressing or cohabiting with species of adjacent biomes. Typically marginal plants were the most sensitive. Key findings: Overlapping adequate habitats are concentrated in the NBC. The analysis of habitats in relation to anthropized areas and CUs demonstrate low future effectiveness in the protection of these savannas, indicating the need to create CUs that consider the potential effects of climate change.

The sharp rise in anthropogenic activities and climate change have caused the extensive degradation of grasslands worldwide, jeopardising ecosystem function and threatening human well-being. Toxic weeds have been constantly spreading in recent decades; indeed, their occurrence is considered to provide an early sign of land degeneration. Policy makers and scientific researchers often focus on the negative effects of toxic weeds, such as how they inhibit forage growth, kill livestock and cause economic losses. However, toxic weeds can have several potentially positive ecological impacts on grasslands, such as promoting soil and water conservation, improving nutrient cycling and biodiversity conservation, and protecting pastures from excessive damage by livestock. We reviewed the literature to detail the adaptive mechanisms underlying toxic weeds and to provide new insight into their roles in degraded grassland ecosystems. The findings highlight that the establishment of toxic weeds may provide a self-protective strategy of degenerated pastures that does not require special interventions. Consequently, policy makers, managers and other personnel responsible for managing grasslands need to take appropriate actions to assess the long-term trade-offs between the development of animal husbandry and the maintenance of ecological services provided by grasslands.

Fluorescent pseudomonads represent one of the largest groups of bacteria inhabiting the surfaces of plants, but their genetic composition in planta is poorly understood. Here, we examined the population structure and diversity of fluorescent pseudomonads isolated from sugar beet grown at two geographic locations (Oxford, UK and Auckland, New Zealand). To seek evidence for niche adaptation, bacteria were sampled from three types of leaves (immature, mature and senescent) and then characterized using a combination of genotypic and phenotypic analysis. We first performed multilocus sequence analysis (MLSA) of three housekeeping genes (gapA, gltA, acnB) in a total of 152 isolates (96 from Oxford, 56 from Auckland). The concatenated sequences were grouped into 81 sequence types and 22 distinct operational taxonomic units (OTUs). Significant levels of recombination were detected, particularly for the Oxford isolates (rate of recombination to mutation (r/m) = 5.23 for the whole population). Subsequent ancestral analysis performed in STRUCTURE found evidence of six ancestral populations, and their distributions significantly differed between Oxford and Auckland strains. Next, the ability to grow on 95 carbon sources was assessed using the BiologTM GN2 microtiter plates. A distance matrix was generated from the raw growth data (A660) and subjected to multidimensional scaling (MDS) analysis. There was a significant correlation between the substrate utilization profiles and MLSA genotypes. Both phenotypic and genotypic analyses indicated presence of a geographic structure for strains from Oxford and Auckland. Significant differences were genotypically detected between strains isolated from immature versus mature/senescent leaves. The fluorescent pseudomonads thus showed an ecotypic population structure, suggestive of adaptation to both geographical and local plant environments.

European starlings (Sturnus vulgaris) represent one of the most widespread and problematic avian invasive species in the world. Understanding their unique population history and current population dynamics can contribute to conservation efforts and clarify how evolutionary processes play out over short timescales. European starlings were introduced to Central Park, New York in 1890, and from a founding group of about 100 birds, they have expanded across North America with a current population of approximately 200 million. There were also multiple introductions in Australia in the mid-19th century, and at least one introduction in South Africa in the late 19th century. Independent introductions on these three continents provide a robust system to investigate invasion genetics. In this study, we compare mitochondrial diversity in European starlings from North America, Australia and South Africa, and a portion of the native range in the United Kingdom. Of the three invasive ranges, the North American population shows the highest haplotype diversity and evidence of both sudden demographic and spatial expansion. Comparatively, the Australian population shows the lowest haplotype diversity, but also shows evidence for sudden demographic and spatial expansion. South Africa is intermediate to the other invasive populations in genetic diversity but does not show evidence of demographic expansion. In previous studies, population genetic structure was found in Australia, but not in South Africa. Here we find no evidence of population structure in North America. Although all invasive populations share haplotypes with the native range, only one haplotype is shared between invasive populations. This suggests these three invasive populations represent independent subsamples of the native range. The structure of the haplotype network implies that the native range sampling does not comprehensively characterize the genetic diversity there. This study represents the most geographically widespread analysis of European starling population genetics to date.

Abstract: Sensitivity to bitter tastes provides animals with an important means of interacting with their environment and thus, influences their dietary preferences. Genetic variants encoding functionally distinct receptor types contribute to variation in bitter taste sensitivity. Our previous study showed that two nonsynonymous sites, A52V and Q296H, in the TAS2R20 gene are directionally selected in giant pandas from the Qinling Mountains, which are speculated to be the causative base-pair changes of Qinling pandas for the higher preference for bamboo leaves in comparison with other pandas. Here, we used functional expression in engineered cells to identify agonists of pTAS2R20 (i.e. giant panda’s TAS2R20) and interrogated the differences in perception in the in vitro responses of pTAS2R20 variants to the agonists. Our results show that pTAS2R20 is specifically activated by quercitrin and that pTAS2R20 variants exhibit differences in the sensitivity of their response to the agonist. Compared to pTAS2R20 in pandas from other areas, the receptor variant with A52V and Q296H, which is most commonly found in Qinling pandas, confers a significantly decreased sensitivity to quercitrin. We subsequently quantified the quercitrin content of the leaves of bamboo distributed in the Qinling Mountains, which was found to be significantly higher than that of the leaves of bamboo from panda habitats in other areas. Our results suggest that the decreased sensitivity to quercitrin in Qinling pandas results in higher-quercitrin-containing bamboo leaves to be tasting less bitter to them and thus, influences their dietary preference. This study illustrates the genetic adaptation of Qinling pandas to their environments and provides a fine example of the functional effects of directional selection in the giant panda.

Yancheng National Nature reserve is included in UNESCO international man and the biosphere reserve area with the critical purpose of conserving, protecting, and providing overwintering habitat for endangered bird species as Red-crane bird. The core zone of the nature reserve is strict, guarded, and prohibited from any anthropogenic pressure. However, Remote sensing technology such as multispectral and hyperspectral satellite imaging with UAV technology was used in surveilling and monitoring the vegetation distribution pattern changes and phenology of its ecosystem from 2003-2018 (15 Years). Support vector machine and Maximum Likelihood classification were used as a multiple classifier in the training of vegetation ecotones, which helps in solving the confusion matrix and maximizing the accuracy assessment of various vegetation land cover in YNNR. Furthermore, Suaeda Salsa, a native grass in the zone and mostly preferred habitat for foraging, breeding, and overwintering by these endangered bird species, are extensively being threatened by invasive cordgrass Spartina Alterniflora and its native counterpart Phragmites Australis. These salt marshes are shrinking out the living and dominating the ecosystem of Suaeda Salsa in YNNR. Also, Spartina Alterniflora is currently suffering from cliff erosion at the shoreline, which in turn reverses the morphology and growth pattern of the cordgrass from seaward direction growth to the inland direction.