Abstract Cellular organisms function as sophisticated molecular systems, orchestrating molecules and reactions for complex construction and environmental interactions. Examination of ciliates provides significant insights into cellular processes. The integration of ciliate observations with genetic and molecular analyses enhances our understanding of their behaviour and activity patterns. The diverse behaviours of ciliates, which have evolved in terms of activity and sensing, inform multiple fields, including genetics, toxicology, ecology, biochemistry, and molecular biology. Furthermore, the study of subcellular structures in ciliates offers innovative research opportunities and positions them as potential model organisms. Studies on ciliates provide insights into pathogen elimination, host-symbiont dynamics, and the molecular function of metazoan organelles. Researchers have investigated epigenetic regulation and molecular pattern formation during ciliate cell division. The rapid generation and growth rates of ciliates make them ideal for studies of population, predator-prey, and food-web dynamics. Protozoa are also suitable for studying epigenetics, aging, genome modifications, and cellular processes.
Genetic diversity is critical for the long-term viability of wildlife populations. While classical population genetic models assume random mating and dispersal, social behavior might violate these assumptions and shape genetic structure. This effect is especially relevant in small populations, where genetic drift and non-random mating can have pronounced impacts. We studied the reintroduced population of Asiatic wild asses ( Equus hemionus ) in the Negev Desert, characterized by fission-fusion social-structure, to investigate how social behavior influences genetic structure. We combined behavioral observations and non-invasive genetic sampling. DNA was extracted from fecal samples collected across the range of distribution around water sources (population’s activity centers). Direct observations showed that only 24–37% of males were dominant (territorial males that breed), with some maintaining dominancy for at least four years, indicating a strongly polygynous mating system. Genetic analyses of mitochondrial and nuclear markers using F-statistics and a network-based approach ( Netstruct analysis ) indicated a fine-scale population genetic structure. This structure had developed over a small geographical range, suggesting either historical founder effects or contemporary limitations to gene flow. The long dominance tenures of territorial males and their high fidelity to water sources may reduce dispersal between activity centers leading to genetic differentiation. These findings highlight the role of social behavior, particularly mating system, in shaping population genetic structure. They emphasize the importance of long-term genetic monitoring and integrating social-structure into conservation planning. For example, management actions to enhance connectivity within the population could include adding water sources between activity centers to facilitate gene flow.
This study provides the first analysis of length-weight relationships (LWR), length-length relationships (LLR), and condition factors for nine fish species from Bakhira Wetland, Uttar Pradesh, based on 898 specimens collected via experimental fishing. Species studied include Puntius chola, P. sophore, Pethia ticto, Systomus sarana, Rasbora daniconius, Amblypharyngodon mola, Devario devario, Nandus nandus, and Channa punctata. Analyses assessed whether LWR followed isometric growth (b=3) and LLR showed linearity (b=1), alongside the calculation of condition factors (K, Kn, Ka) and regression parameters (a, b, R'). Three species (P. sophore, A. mola, S. sarana) showed isometric growth, three (P. chola, R. daniconius, C. punctata) positive allometric growth (b>3), and three (P. ticto, N. nandus, D. devario) negative allometric growth (b<3). Most species showed non-isometric LLRs (bb1), except A. mola, S. sarana, and N. nandus. Condition factor K ranged from 0.832 (R. daniconius) to 1.606 (P. ticto); Kn from 0.999 (R. daniconius) to 1.008 (A. mola); and Ka from 0.35 (R. daniconius) to 1.805 (P. ticto). Results indicate interspecific differences in growth, likely influenced by diet or physiology, offering a valuable baseline for future biological studies, stock assessments, and conservation efforts in the wetland.
Plant species composition is crucial for ecosystem functioning because it influences both ecosystem stability and productivity. Plant species composition is affected by abiotic factors such as environmental moisture and soil properties, as well as biotic influences related to land use and management, which include herbivore grazing. The objective of this study was to compare vegetation structure and composition between protected and adjacent unprotected areas in Gauteng Province, South Africa. Vegetation surveys were conducted at Abe Bailey Nature Reserve (ANR), Roodeplaat Dam Nature Reserve (RNR), and Suikerbosrand Nature Reserve (SNR). Three sites within each nature reserve were paired with adjacent unprotected sites, where species composition and soil chemical properties were determined in Modified-Whittaker plots (MWPs). Plant species were recorded in 18 MWP plots of 1000m2 area, and also species cover, density, and growth forms were recorded in 180 subplots of 1m2 area. We determined similarity in species composition between paired sites using the Jaccard and Sorensen similarity indices, as well as the Bray-Curtis dissimilarity index. We further assessed variations in species composition between study locations and their relations with soil properties using Detrended Correspondence Analysis and Canonical Correspondence Analysis. There was low species composition similarity between the two land use types, but between locations, the ANR and SNR sites showed the most similarity in species composition. The soil variables differed significantly at some paired sites and also between locations. In general, the results indicated a strong association between species composition and environmental factors, specifically soil properties and herbivore grazing intensity.
Festuca abyssinica is a perennial and endemic to Africa. It grows along the mountain ranges of eastern Africa to Zimbabwe, the Tibesti mountains of Chad, the Cameroon highlands, Bioko, and the highlands of Angola. Under warming scenarios, climate change will induce upward species movements. The net movement of species to higher altitudes could lead to the disappearance and decline of species in the lower elevations. Therefore, this study aimed to 1) model the current and predict the future distributions of F. abyssinica as a function of the climate change scenarios, 2) explore the environmental factors causing the shifts in its habitat ranges, and 3) identify the its current and future suitable habitats in the Mountains of East African Countries (Ethiopia, Kenya, Tanzania, and Uganda). The species distribution model analyses were performed for the current (1970-2000) and the future climate (from 2061-2080) periods for two shared socio-economic pathways (SSP), SSP 245 and SSP 585 carbon emission scenarios, with the spatial resolution of 30 seconds. For the future climate data, the global climate model (GCM) HadGEM3-GC31-LL was used from the Coupled Model Intercomparison Project Phase 6 (CMIP6). The baseline bioclimatic data and GCM were downloaded from the WorldClim database. The ensemble modelling was run by using RF, MARS, SVM, and MaxEnt to minimize the errors and enhance the predictive performance of the models. Bootstrap with ten replications was applied to fit the models using the 281 occurrence points and background data (n=281) within the R statistical program (version: 4.4.0). The result of the prediction model showed that, under the SSP245 scenario, the suitable habitat of F. abyssinica decreases by 1.07%. However, under the SSP585 scenario, 40.53% new highly suitable habitats across East African mountains were identified during the years 2061-2080 when compared with the habitat suitability area under the current climate scenario.
Understanding the above- and below-ground biomass allocation is crucial for accurately predicting the impacts of vegetation on carbon cycling. However, the spatial and temporal patterns of above- and below-ground biomass allocation in China’s forests remain largely unknown. We conducted a comprehensive estimation of above- and below-ground biomass allocation in China’s forests using the above- and below-ground biomass carbon pool dataset (with a spatial resolution of 1 km grid) from 2002 to 2021. Our results demonstrate for the first time that, within China’s forest ecosystems, the root-to-shoot (R/S) ratio (usually defined as the ratio of below-ground biomass (BGB) to above-ground biomass (AGB)) was higher in the northern regions compared to the southern regions, suggesting a greater allocation of carbon to below-ground components in plants from the northern areas. Temporally, we observed a significant decline in R/S ratios. The relative importance ranking from random forest analysis reveals that the Mean Diurnal Range (TDR) was the most critical factor regulating the spatial and temporal variability of above- and below-ground biomass allocation. These findings provide a foundational understanding of forest ecosystem carbon dynamics, shedding light on the complex interplay between above- and below-ground components.
The Grivet monkey (Chlorocebus aethiops aethiops) is an Old World primate distributed east of the White Nile from Sudan to Ethiopia, Eritrea, and Djibouti. We studied the diet composition and preference of Grivet monkeys in and around Wondo Genet College of Forestry and Natural Resources in Ethiopia from February 2021 to June 2022 during both the wet and dry seasons, using the instantaneous scan sampling method at 15-minute intervals for up to 10 minutes. The line transect method and plot sampling were used to collect data on the availability of plant-based food items in the sampling sites. Descriptive statistics and inferential statistics, such as the Kruskal-Wallis test and Mann-Whitney U test, were used to analyze the data. Grivet monkeys consumed 47 food sources grouped into 41 plant species - 27 wild plants, 14 field crops, 5 cooked food types, and 1 insect - during the entire season. On average, forb leaves (32 +/- 3.2%) and fruits (26 +/- 2.5%) comprised the highest percentage of their diet, whereas the `roasted grain' (0.1 +/- 0.1%), roots (0.3 +/- 0.2%), and insects (0.5 +/- 0.4%) comprised the lowest. Psidium guava, Desmodium intortum, and Persea americana were the three most common plant species, and Coffee arabica, Bidens pilosa, and Callistemon linearis were the least common plant species preferred by the grivet monkey. Grivet monkeys consumed more food during the dry season than during the wet season. We therefore recommend that the regional government should stop deforestation and rehabilitate the natural forests. Sustainable management is needed for the top preferred plant species to allow grivet monkeys to optimize their diet.
Significant uncontrolled urbanization due to enormous developmental activities, along with encroachment, led to higher human-wildlife conflict (HWC) in the newly notified Amchang Wildlife Sanctuary located within the Guwahati Metro City of Assam, India. An assessment was carried out in five villages under the Chandrapur Block, Kamrup (M), Assam, India, between 2019 and 2021 using a questionnaire and field survey methods to find out the status of HWC at the fringe area of Amchang Wildlife Sanctuary. The majority of the respondents (71.66%) stated that elephants were solely responsible for HWC, followed by leopards in the study area. The primary cause of human-elephant conflict (49.17%) was found to be a shortage of food and water. The majority of respondents (59.17%) reported having house damage, followed by other property damage. Lone/small herds of elephants were responsible for the majority (87.5%) of all incidents. On the other hand, the decline in wild prey was identified as the primary cause (54.17%) of human-leopard conflict. Goats were the main prey of leopards (70.63%), followed by dogs (12.59%), pigs (10.49%), cows (4.19%), and buffalo (2.1%). The study further suggests that residents should remain vigilant during the evening, as the majority of elephant raids or leopard attacks occurred during this period. Various measures like patrolling, building a trench, electric fencing, etc., were suggested by the affected villagers for mitigating HWC in this landscape.
Oil spills in terrestrial environments, particularly in arid ecosystems, can have long-lasting ecological consequences due to slow natural degradation processes and limited water availability. In December 2014, a major crude oil spill occurred in the Evrona Nature Reserve in southern Israel's Arava Valley, releasing approximately 5 million liters of oil into a fragile desert ecosystem. In response, bioremediation was employed as a primary mitigation strategy due to its ecological compatibility and potential to enhance microbial degradation of hydrocarbons. This study evaluates the effectiveness of different bioremediation treatments in promoting the degradation of total petroleum hydrocarbons (TPH) in contaminated soils at Evrona. We assessed TPH concentrations, total organic carbon (TOC), and the proliferation of TPH-degrading bacteria across three soil depths (0, 15, and 25 cm) and over one month, using a combination of chemical analyses and colony-forming unit (CFU) counts. Treatments included the application of Oil Spill Eater (OSE) alone and OSE in combination with either oil-binding (OB) agents or petroleum remediation product (PRP). Our results show a clear and significant reduction in TPH concentrations over time, particularly at deeper soil layers, indicating depth-dependent degradation. In contrast, TOC levels remained stable, suggesting that the degradation of TPH did not significantly alter the overall organic carbon pool. Bacterial growth analysis revealed that while OSE alone had minimal impact, its combination with OB or PRP significantly enhanced microbial activity. These findings support the use of integrated bioremediation strategies in arid regions and highlight the importance of microbial stimulation for effective hydrocarbon degradation.
Interspecific interactions and correlations provide vital insights into species relationships and the overall stability of plant communities, which are essential for understanding the dynamics of vegetation restoration and biodiversity conservation. This study examined the interspecific associations and correlations within the evergreen broadleaved forest of Bidoup-Nui Ba National Park in southern Vietnam. The investigation was based on a comprehensive survey of all trees with a diameter at breast height (DBH) greater than 2.5 cm within a 4-ha study plot. A variety of analytical methods, including variance ratio (VR), chi-square test, association coefficient (AC), Ochiai Index, Pearson and Spearman correlation coefficients, and principal component analysis (PCA), were employed to assess the relationships among twelve dominant tree species. The results revealed the following key findings: (1) the community exhibited predominantly positive associations, suggesting a stable successional phase; (2) the ratio of positive to negative correlations exceeded 1, with a significantly higher number of positive correlations, reflecting stronger interspecific associations; (3) Spearman’s rank correlation test demonstrated greater sensitivity compared to other correlation methods; and (4) the classification of ecological species groups aligned with the correlation results, emphasizing the substantial influence of ecological traits and resource utilization strategies on interspecific relationships. These findings highlight the critical role of interspecific interactions in maintaining community stability and provide valuable insights for advancing ecosystem restoration and biodiversity conservation strategies.
Abstract Temperature is a key driver of individual physiology and ontogeny in ectotherms, with important consequences for individual fitness and population dynamics. Freshwater ectotherms typically grow and develop faster but reach smaller adult sizes at higher temperatures, a pattern known as the “temperature-size rule” (TSR). However, temperature-size responses can vary across ontogeny. Some freshwater arthropods also adjust the number of larval moults, offering additional developmental flexibility that could modulate temperature-size responses. We investigated the temperature dependence of the larval development of Sympetrum striolatum , a widespread univoltine dragonfly with variable number of larval instars. Larvae were reared from egg to final larval instar at six constant temperatures (9, 13, 17, 21, 25, and 29 °C). We assessed number of moults, developmental rate and body size of selected instars, and measured the metabolic rate at the last larval instar (F0). No hatching occurred at 9 °C, and all larvae died early at 29 °C, indicating a narrow thermal window for development (< 20 °C range). Development rate increased with temperature between 13 °C and 25 °C. While early instars followed TSR expectations, with smaller size at higher temperatures, final body size increased with temperature due to more larval moults and larger size increments in later instars at higher temperatures. Metabolic rate at 21 °C was significantly lower in individuals reared at 25 °C, indicating thermal acclimation under thermal stress. These findings reveal complex, stage-specific responses to temperature and highlight the developmental plasticity of S. striolatum . Our results provide insights into how freshwater ectotherms with flexible development strategies may cope with climate change.
Behavioral and evolutionary ecology made enormous progress in the last 50 years by using the assumption that the modeler/observer is external to the organism and its environment. This allows specifying details of the environment (e.g. predation risk or the probability of finding food) and then using a fitness optimization model to predict the behaviors that are the end point of natural selection. Doing so can be called the third-person perspective of the organism. More than 80 years ago, Jakob von Uexküll argued that a first-person perspective is possible if we replace the external observer’s description of the environment by the organism’s subjective characterization of itself and its surroundings based on its sensory data, and allow those sensory data to shape behavior. The first-person umwelt model becomes an evolutionary one when the genes determining the sensory responses evolve. I use a canonical problem of habitat selection (which will always be an important problem in biology and which was one of Leon Blaustein’s favorite topics of research) to illustrate construction of first-person umwelt and third-person fitness optimization models. A canonical problem is the simplest but still interesting form of a collection of similar problems, with a focus on what is essential to the collection as a whole. In particular, a canonical problem does not model any particular situation, but has much in common with many situations. Here, the canonical problem focuses on an organism that needs to find a refuge from a harsh environmental season that begins at a fixed time when refuges vary in the level of protection from the harsh environment. Individuals who survive the harsh environmental season successfully reproduce. When searching for refuges, organisms experience predation risk so that the third-person fitness optimization model answers “when an organism encounters a habitat of a specific quality at a given time, is it predicted to settle or continue searching”? The first-person umwelt model is based on the assumptions that i) the organism has sensory inputs that provide information on quality of a habitat (settling is more likely in higher quality habitats) and the remaining time before the onset of the harsh environmental season (settling is more likely when less time remains), ii) the sensory information is combined to determine behavior, and iii) the genotypic architecture underlying the sensory functions evolves by natural selection. After developing predictions from the models by simulating populations following the rules developed from each, I use effect size measured by Cohen’s d to explore how evolution of the genes of the response functions in the first-person umwelt model affects survival and convergence of the predictions of the first-person umwelt and third-person fitness optimization models.
Camouflage and crypsis are key survival strategies for many animals, enabling them to evade predators or enhance their ability to ambush prey. For cryptic species, effective camouflage requires not only morphological adaptations but also behavioral tactics that ensure individuals select appropriate microhabitats. However, how polymorphic cryptic species match their phenotype to their environment remains poorly understood. In this study, we investigated the morphological and behavioral plasticity of the polymorphic mantis Sphodromantis viridis from Mediterranean and desert populations to determine whether habitat selection and coloration occur when nymphs are reared in the absence of environmental color. We reared naive individuals in color-neutral conditions and examined their morphology, development time, body length, and microhabitat preferences. Color in S. viridis is sex-linked, with males exhibiting higher proportions of brown coloration than females, and color change occurs unidirectionally from green to brown. Desert males displayed greater variance in body size and development time, forming two distinct morphs: one is smaller, greener, and matures before females, and another is larger, browner, and matures after females, suggesting alternative reproductive strategies. Neither nymphal nor adult coloration of naive mantids influenced color choice in controlled conditions. Our findings suggest that S. viridis nymphs showed ontogenetic color change in the absence of environmental cues, which may reflect evolutionary adaptations to seasonal changes: green in spring when the vegetation is still green and brown later on when annuals dry out. Further studies on background-dependent rearing conditions could clarify how experience influences microhabitat choice.
The Arabian leopard (Panthera pardus nimr) once roamed the arid mountains of Israel but is now extirpated from the region. This study accounts for the communication behaviors observed in five radio-collared individuals monitored over multiple years in the Judean Desert. We documented vocal, olfactory, and visual communication patterns in ahighly arid and topographically complex environment using GPS telemetry, direct observations, and systematic surveys. Scrape marking was the most frequent form of chemical signaling, with a strong preference for vegetated substrates, likely to preserve scent longevity and minimize detection by non-target species. Marking activity was closely tied to reproductive status, with elevated frequency during estrus in females. Vocalizations, including roaring, were context-dependent and most commonly associated with mating and territorial interactions. Rare visual behaviors, such as cheek rubbing and tree clawing, were also observed and may serve secondary communicative roles. These findings align with communication strategies observed in other solitary felids, emphasizing the importance of indirect signaling in maintaining social structure. Though the Arabian leopard is extinct in Israel, our results provide rare behavioral insights vital for conservation planning in regions where the subspecies persists. Protecting suitable habitats and ecological corridors that enable natural communication behavior is essential for sustaining viable leopard populations under increasing anthropogenic pressure.
