Aim: Worldwide climate-driven shifts in the distribution of species is of special concern when it involves habitat-forming species. In the coastal environment, large Laminarian algae – kelps – form key coastal ecosystems that support complex and diverse food webs. Among kelps, Macrocystis pyrifera is the most widely distributed habitat-forming species and provides essential ecosystem services. This study aimed to establish the main drivers of future distributional changes on a global scale and use them to predict both future habitat suitability. Location: Global Methods: Using species distribution models (SDM), we examined the changes in global distribution of M. pyrifera under different emission scenarios with a focus on the Southeastern Pacific shores. To constrain the drivers of our simulations to the most important factors controlling kelp forest distribution across spatial scales, we explored a suite of environmental variables and validated the predictions derived from the SDMs. Results: Minimum sea surface temperature was the single most important variable explaining the global distribution of suitable habitat for M. pyrifera. Under different climate change scenarios, we always observed a decrease of suitable habitat at low latitudes, while an increase was detected in other regions, mostly at high latitudes. Along the Southeast Pacific, we observed an upper range contraction of -17.08°S of latitude for 2100 under the RCP8.5 scenario, implying a loss of habitat suitability throughout the coast of Peru and poleward to -27.83°S in Chile. Along the area of Northern Chile where a complete habitat loss is predicted by our model, natural stands are under heavy exploitation. Main conclusions: The loss of habitat suitability will take place worldwide: significant impacts on marine biodiversity and ecosystem functioning are likely. Furthermore, changes in habitat suitability are a harbinger of massive impacts in the socio-ecological systems of the Southeastern Pacific.
Arachis pintoi (Fabaceae) is a common relative of the cultivated peanut, and folds its four leaflets up to look like one at night. The adaptive significance of this behavior (foliar nyctinasty) is unknown. To test the hypothesis that leaflet folding alone can deter herbivores, a leaf preference experiment was performed on Chromacris trogon grasshoppers. Small oval cutouts were made from leaves of the grasshopper’s preferred food source, Iochroma arborescens (Solanaceae), and were combined with small pieces of tape and dry grass to construct artificial leaves resembling the day and night form of A. pintoi. In the experiment, groups of three grasshoppers were starved for 24 hours and then placed in petri dishes containing one closed and one open artificial leaf. After 30 six-hour trials, the average herbivory of open leaves was 12.3%, while closed leaves was 5.2% (p = 0.00145), indicating a significant preference for open leaves. This suggests that the folded configuration of A. pintoi leaves can be a defense against herbivory.
1. While territoriality is one of the key mechanisms influencing carnivore space use, most studies quantify resource selection and movement in the absence of conspecific influence or territorial structure without inference on resource selection processes. 2. Our analysis incorporated intra-specific competition in a resource selection framework, via territorial data of conspecifics, to investigate mechanisms of territoriality and to better understand the role of neighboring packs on African wild dog habitat selection. We fit integrated step selection functions to 3-hour GPS data from 12 collared wild dog packs in the Okavango Delta, and estimated selection coefficients using a conditional Poisson likelihood with random effects. 3. Packs selected for the outline of their neighbors’ 30-day boundary (defined as their 90% kernel density estimate), and for the outline of their own 90-day core (defined as their 50% kernel density estimate). Neighbors’ 30-day boundary had a greater influence on resource selection than any habitat feature. Habitat selection differed when they were within versus beyond their neighbors’ 30-day boundary. 4. Pack size, pack age, pup presence, and seasonality all mediated how packs responded to neighbors, and seasonal dynamics altered the strength of residency. While newly-formed packs and packs with pups avoided their neighbors’ boundary, older packs and those without pups selected for it. Packs also selected for the boundary of larger neighboring packs more strongly than that of smaller ones. 5. Social structure within packs has implications for how they interact with conspecifics, and therefore how they are distributed across the landscape. Future research should continue to investigate how territorial processes are mediated by social dynamics and, in turn, how territorial structure mediates resource selection and movement. These results could inform the development of a human-wildlife conflict (HWC) mitigation tool by co-opting the mechanisms of conspecific interactions to manage space use of endangered carnivores.
Genetic studies of Domesticated-Weed-Wild Complexes (DWWC) have typically focused on one-way introgression of crop alleles into wild or weedy populations, with little consideration of the entire natural ecosystem. In Sri Lanka, DWWC is diverse, comprising six evolutionarily discrete groups in the genus Oryza. Using 33 neutral simple sequence repeat (SSR) loci, we characterized six Oryza groups to understand the genetic background and evolution of DWWC components. Our analysis found that Oryza groups have large population sizes and high inter-group long-term gene flows. Asymmetric gene flows were found between wild and weedy rice groups, but the rare alleles shared among DWWC components provide additional evidence for extensive and enduring exchange, highlighting the dynamic nature of this complex genetic admixture among different Oryza lineages. We found high genetic diversity at the population and species levels due to mixed DWWC components over the generations. Weedy rice types exhibit genetic incorporation through admixture from both crop and wild species, highlighting the multi-way genetic transfer in the evolution of weedy rice types. Our findings support the idea that the DWWC is an integrated complex in the Sri Lankan rice ecosystem and that its weedy rice has multiple origins, including de-domestication via feralization of cultivated rice, inter-varietal hybridization among distinct cultivated rice types, adaptation, and invasion of rice cultivation areas by wild Oryza species, and hybridization events between crop and wild rice populations. Abandoned rice domesticates can also evolve into weedy forms with less intimate human relationships and contaminate the rice ecosystem.
The invasion of alien plant species poses a threat to native community’s composition and diversity. However, the invasiveness of alien plants and invisibility of native communities should be depended on the interactions between biotic and abiotic factors, such as natural enemies and nutrient availability. In a study, we simulated the invasion of nine invasive plants into native plant communities with two levels of nutrient availability and natural enemies suppression. We explored how the biotic and abiotic factors affect the response of alien target species and the resistance of native communities to invasion. The results showed that enemy release (i.e., presence of enemy) increased biomass proportion of alien plants and decreased that of native community under without nutrient addition. Furthermore, we also found that the negative effect of enemy suppression on the evenness of native community and the root-to-shoot ratio of alien target species was greatest under nutrient addition. Therefore, nutrient deficiency and natural enemies might promote the invasive success of alien species in native community, whereas nutrient addition and enemy suppression can better enhance the resistance of native plant communities to invasion.
1. Over the last four decades coral disease research has continued to provide reports of disease states, the occurrence and severity of disease outbreaks, and associated disease signs however nomenclature and protocols for microscopic disease descriptions have yet to be implemented. Histopathology using systematic protocols is a gold standard for the microscopic assessment of diseases in veterinary and medical research. Increasing disease outbreaks on coral reefs as human impacts intensify highlights the need to also establish standardised diagnostic terminology and methodology for coral disease research. 2. Here we apply a systematic approach to collating, reviewing, and evaluating histopathological methods used to study white diseases in hard coral taxa and map research effort in this field spanning study design, sample processing and analysis in the 33 publications identified between 1984 and 2022. 3. We find that studies to-date have not uniformly detailed methodologies, and terminology associated with histopathological reporting and disease description is inconsistent between studies. Combined these limitations reduce study repeatability, limiting the uptake of histopathology in coral disease research and the capacity for researchers to compare disease reports. 4. A primary outcome of this study is revision of the most widely used terminology applied to coral tissue and development of recommendations for standardised reporting procedures with the aim of increasing accessibility and uptake of histopathology in addition to allowing for ongoing comparative analysis through living systematic reviews for the coral disease field.
We report the first case of egg burying behaviour in a neotropical direct-developing frog. An amplectant pair of Pristimantis chocoensis was found and we recorded oviposition and the subsequent burying of the clutch by the female. Both parents remained near the nest during the following day. This rare observation sheds light over the intricate reproductive behaviours of terrestrial amphibians and suggests that the evolution of direct development has selected for highly specialized forms of parenting.
Soil fungi are involved in the decomposition of organic matter, and they alter soil structure and physicochemical properties and drive the material cycle and energy flow in terrestrial ecosystems. Grazing exclusion is one of the most common measures used to restore degraded grasslands worldwide. However, changes in soil fungal community characteristics during grazing exclusion in different types of grasslands are unknown. Here, we investigated the effects of a 9-year grazing exclusion on soil properties, fungal community composition and diversity in three grassland types (temperate desert, temperate steppe and mountain meadow). The results showed that in the 0-5 cm soil layer, grazing exclusion significantly affected the physicochemical parameters of all three studied grassland types. In the 5-10 cm soil layer, grazing exclusion significantly increased total phosphorus (TP) in temperate deserts by 34.1%, while significantly decreasing bulk density (BD) by 9.8% and the nitrogen: phosphorus ratio (N:P) by 47.1%. The soil fungal community composition differed among the grassland types, For example, significant differences were found among the three grassland types for the Glomeromycota and Mucoromycota, Grazing exclusion, grassland type, and the interaction between the two did not significantly affect soil fungal α-diversity or community composition(P > 0.05), but significantly altered fungal β-diversity (P < 0.05). Overall, our results highlight the importance of soil nutrient content, especially soil Kjeldahl nitrogen, total phosphorus and organic carbon on fungal diversity, and the results provide key insights into how soil fungi respond to grazing exclusion in different grassland types.
Against the backdrop of global warming, marine heatwaves are projected to become increasingly intense and frequent in the future. This trend poses a potential threat to the survival of corals and has the capacity to lead to the destruction of entire coral reef ecosystems. Although many studies have confirmed the resilience of corals to heat stress, but their ability to withstand repeated heatwave events occurring in nature remains unclear. In this study, focusing on physiological and symbiotic microorganism responses, we examined the adaptation and resilience of Turbinaria peltata after repeated exposed to marine heatwaves. In the first heatwave, From physiological perspective, Turbinaria peltata showed the average values of Chl a and endosymbionts increased, while GST, Caspase-3, CAT, and SOD showed significant decreases (p < 0.05) upon repeated exposure to heatwaves compared to the initial exposure. In terms of bacteria, the abundance of Leptospira which functional prediction indicating potential pathogenicity and intracellular parasitism, increased significantly during the initial exposure to the heatwave. In contrast, probiotic bacteria such as Achromobacter arsenitoxydans and Halomonas desiderata, which might related to mobile elements, biofilm formation, stress-tolerant bacteria, Gram-positive bacteria, nitrogen uptake, and nitrate uptake, showed significant increases during the re-exposure to the heatwave. Overall, the results indicate that Turbinaria peltata adapts to marine heatwaves through physiological regulation and changes in the microbial community.
Dung beetle serve as valuable indicators for studying environmental changes and as model systems for exploring ecosystem functionality. By analyzing the diversity and composition of gut microbiota in Catharsius molossus under starvation and refeeding conditions, this study investigates the effects of dietary states on the gut microbiota of these insects. Artificial rearing methods, along with 16S rRNA high-throughput sequencing and bioinformatics, were used to analyze Catharsius molossus gut microbiota under varying dietary conditions. The results indicate that at the phylum and genus levels, the gut microbiota of Catharsius molossus under refeeding conditions is more diverse than that under starvation conditions, with seven phyla and twenty-two genera showing significant differences (P < 0.05). In terms of functional prediction, the predicted functional genes of the gut microbiota were annotated to the KEGG database, revealing significant differences in thirty-two metabolic pathways at the third level (P < 0.05). Furthermore, it provides functional prediction information related to specific microbial taxa. Additionally, Dysgonomonas is speculated to participate in nitrogen fixation, and the gut microbiota of Catharsius molossus may potentially serve as a source of antimicrobial agents like anshanmycin. These findings provide novel insights into Coleoptera ecosystem microbial interactions and offer theoretical support for future applications.
The current knowledge on insects preying on fruits is limited, and some of the scarce existing data on fruit-associated insects are secluded within the host institutions. Consequently, their value is not fully realized. However, the integration and interlinking of historical biocollections data of plants, fruits, and insects, collected in Kenya, within a digital framework have not been fully exploited. This necessitates the need to enhance accessibility by consolidating the historical biodiversity data onto a unified platform. To address these gaps, this article presents a description of the development of a web-based platform for data sharing and integrating biodiversity historical data of wild plants, fruits, associated insects, and their molecular barcodes (WiPtFruIM) while leveraging data science technologies. The platform holds invaluable potential in fruit pest management, by providing information on potential biocontrol agents for fruit pests, which can function as a decision-making tool and fruit-pest ecological modeling. The platform is invaluable information to a worldwide community (such as researchers, classroom education, nature enthusiasts, fruit pest management, modeling, etc.) to make informed decisions and build innovative tools.
In the Arctic tundra, recurrent periods of food scarcity force predators to rely on a wide variety of resources. In particular most predators use ungulate carcasses as an alternative food supply, especially in winters when live preys are scarce. As important and localized resource patches, carrion promotes co-occurrence of different individuals, and its use by predators is likely to be affected by interspecific competition. Here, we studied how interspecific competition and resource availability impact winter use of carrion by Arctic and red foxes in low Arctic Fennoscandia. We predicted that presence of red foxes limits Arctic foxes' use of carrion, and that the outcome of competition for carrion depends on the availability of alternative food resources, such as rodents. We monitored Arctic and red fox presence at experimentally supplied carrion using camera traps, between 2006 and 2021 in late winter. Using a multi-species dynamic occupancy model at a week-to-week scale, we evaluated use of carrion by foxes, while accounting for the presence of competitors, rodent availability and supplemental feeding provided to Arctic foxes. Competition primarily affected carrion use by increasing both species' probability to leave occupied carcasses to a similar extent, suggesting a symmetrical avoidance. Rodent abundance was associated with an increase in the probability of colonizing carrion for both species. For Arctic foxes, however, this increase was only observed in carcasses unoccupied by red foxes, showing greater avoidance when alternative preys are available. Contrary to expectations, we did not find strong signs of asymmetric competition for carrion in winter. Our results suggest that interactions for resources at a short time scale are not necessarily aligned with interactions at the scale of the population. In addition, we found that competition for carcasses depends on the availability of other resources, suggesting that interactions between predators depend on the ecological context.
Adaptive radiation as a result of ecological opportunity can have profound effects on the evolutionary outcome of species. On coral reefs, parrotfishes have been considered as one of the most dramatic examples of adaptive radiation unique in their extreme dietary specialisation. Using abrasion-resistant biomineralized teeth, parrotfishes are able to mechanically extract protein-rich micro-photoautotrophs growing in and amongst reef carbonate material. This unique ability to exploit a previously untapped trophic resource is thought to have led to the early diversification of the parrotfishes. In order to better understand the key evolutionary innovations leading to the success of these dietary specialists, we sequenced and analysed the genome of the spotted parrotfish (Cetoscarus ocellatus). Our findings reveal significant expansion, selection, and duplication within several gene families responsible for detoxification, including the cytochrome p450 gene family and non-cyp450 carboxylesterases. We find preliminary evidence that the structural mechanism responsible for the extreme hardness and biomineralization of parrotfish teeth may be a result of poly-glutamine expansion in the enamel protein ameloblastin. We also detect expansion and selection for several genes related to pigmentation and sequential hermaphroditism. Together, these results highlight a potentially complex interplay of adaptive radiation and sexual selection operating on coral reef ecosystems.
We present the first videos depicting the consumption of bats by rusty-spotted genets (Genetta maculata) inside a cave in the Republic of Congo. Following the implementation of a camera-trap monitoring protocol of interactions between cave bats and wildlife, we identified important genet activity in one of the caves in our study. Between 2022 and 2023, we recorded four events of bat or rodent consumption (including two with certainty on bats), one hunting attempt on bats and three feeding behaviors on insects. We detail the various behaviors and discuss the potential implications of genets consuming bats, rodents and insects, and in particular scavenging on dead bats. Finally, we address the potential implications of zoonotic pathogen transmission from bats to humans via genets through the bushmeat trade.
Crop wild relatives provide a valuable resource for improving crops. They possess desirable traits that confer resilience to various environmental stresses. To fully utilize crop wild relatives in breeding and conservation programs, it is important to understand the genetic basis of their adaptation. Landscape genomics associates environments with genomic variation and allows for examining the genetic basis of adaptation. In this study, we applied landscape genomics to examine the differences in allele frequency of 15,416 Single Nucleotide Polymorphisms (SNPs) among 153 accessions of wild eggplant relatives from Africa, the principal hot spot of these wild relatives. Further, we explored the correlation between these variations and the bio-climatic and soil conditions at their collection sites. Our results showed that the environment has a greater impact on the genetic variation in the eggplant wild relative populations compared to the geographical distances between collection sites while controlling for population structure. These findings indicate the relevance of the environment in shaping genetic variation in eggplant relatives over time. We detected 396 candidate SNPs associated with ten environmental factors by applying four genotype-environment association methods. Some of these SNPs signal genes involved in pathways that help with adaptation to environmental stresses such as drought, heat, cold, salinity, pests, and diseases. These candidate SNPs will be useful for marker-assisted improvement and characterizing the germplasm of this crop for developing climate-resilient eggplant varieties. The study provides a model for how we can apply landscape genomics to the wild relatives of other crops.
Here, we describe a Raspberry Pi-based camera system that is portable, robust, and weatherproof, with a close-up focus (2.5 cm). We show that this camera system can be used in remote locations with high rainfall and humidity. The camera has an Infrared LED light to film in dark places and can continuously record for 21 days. We also describe how to make concrete artificial shelters to mount the camera in. One of the great strengths of this shelter/camera setup is that the animals choose to take up residence and can then be filmed for extended periods with no disturbance. Furthermore, we give examples of how shelters and cameras could be used to film a range of behaviours in many small cryptic amphibian species, but also other small vertebrates and invertebrates globally.
1: Passive Acoustic Monitoring (PAM) revolutionises ecological research, utilizing sounds for species-specific inferences. However, PAM generates large volumes of data, posing challenges in annotation, classification, and review complexity, necessitating efficient data management strategies. 2: Given this particular need, this research aimed to improve the performance of a pattern-matching algorithm for detecting signals of interest in two nocturnal bird species. The study pursued two main objectives: first, to evaluate various similarity scores and determine the optimum one through a sensitivity-specificity analysis. Second, we investigate potential relationships between species-specific spectral features, such as high, low, and peak frequencies, and the algorithm’s performance by reviewing and comparing their dispersion with a Levene test. 3: The outcomes demonstrated a generally favorable algorithm performance, achieving up to 80% sensitivity and specificity. This underscores its effectiveness in identifying target signals. Our investigation indicated that factors like individuality, which could be reflect on the spectral features, could potentially impact the algorithm’s efficacy. 4: ARBIMON provides transformative collaborative solutions in the field of bioacoustics. However, additional research is imperative to fully grasp the performance and potential applications of such tools. This exploration extends beyond ARBIMON to encompass the burgeoning technologies within the discipline.
Impacts of long-term fertilization and cultivation were evaluated on nematode communities associated with tall fescue turfgrass following 11 years of treatment applications. Fertilizer treatments of biosolid, synthetic, and plant-based fertilizers and cultivation treatments of 0x, 1x, and 2x aerification passes were applied to randomized and replicated tall fescue plots at the University of Maryland Paint Branch Turfgrass facility in College Park, Maryland. Free-living and plant-parasitic nematodes were identified, enumerated, and categorized into functional groups. Nematode count data were compared using generalized linear mixed modeling with negative binomial distribution and two-way ANOVA was used to compare nematode ecological indices. Biosolid treatments resulted in lower omnivore-predator densities than plant-based fertilizer treatments (P≤0.001) and significantly greater Hoplolaimus densities than plant-based fertilizer plots (P≤0.05). Synthetic fertilizer applications resulted in the greatest Eucephalobus (P≤0.05) and total bacterivore densities (P≤0.001) of all fertilizer treatments. Plant-based fertilizer treated plots had the largest Structure Index (P≤0.05). Cultivation of 1x resulted in fewer total bacterivore densities than 2x (P≤0.01) while omnivore-predator densities were greater in 1x than 0x (P≤0.001). Plant health, as measured by NDVI, was lowest in biosolid treated turfgrass (P≤0.05). These findings suggest that long-term turfgrass management practices can have variable impacts on nematode abundance and community structure in tall fescue and provide insights into ecological impacts of turfgrass management practices.