Search Results (186)

Stingless bee colonies are vulnerable to predators of widely varying sizes, and repeated intrusions can cause stress, reduce productivity, and trigger colony absconding. Existing automated surveillance systems detect only a limited range of predators and often struggle with multi-scale object detection in high-resolution images. This study proposes a real-time predator monitoring system that integrates a Multi-Scale Attention module into the YOLOv11-nano architecture (MSYOLO11) to enhance detection performance across both small and large predators. The proposed model combines convolutional features with an attention mechanism to improve global–local feature fusion. Experimental evaluation shows that MSYOLO11 increases overall Recall from 0.830 to 0.853 compared to YOLOv11-nano, with substantial improvements for small-object classes such as ants (+0.096), humans (+0.083), and H. itama (+0.026), while maintaining comparable Precision (0.868 vs 0.842) and mAP50 (0.898 vs 0.896) at a nearly identical computational cost (6.3 GFLOPs). The system operates at 5 FPS on a Jetson Orin Nano, with an end-to-end latency of 181 ms. A Firebase-integrated mobile application delivers instant push notifications, displays detected predators with bounding boxes, and provides real-time data synchronization. The results demonstrate that MSYOLO11 offers a practical and efficient solution for multi-scale predator detection, supporting continuous hive surveillance and timely beekeeper intervention. Full article

The Spur-thighed tortoise (Testudo graeca) is a long-lived terrestrial reptile listed as ‘Vulnerable’ on the IUCN Red List and protected under CITES Appendix II. As an ecosystem engineer, it plays a vital role in Mediterranean landscapes, yet it frequently faces anthropogenic pressures in urban environments. This study provides an ecological and ethological assessment of a captive T. graeca population (n = 42) in the historical Münire Madrasa Handicrafts Bazaar in Kastamonu, Türkiye. The methodology integrated spatial carrying capacity modeling (Boullon model), systematic ethogram-based observations (120 h), and ethnozoological surveys (n = 200). Spatial analysis revealed that the population exceeds the corrected Real Carrying Capacity (RCC ≈ 10) by four times (Overcapacity Index: 4.2) within the 70 m² area. Ethological findings documented chronic stress, with stereotypic pacing (H1) occupying 32% of the time budget, alongside a significant loss of anti-predator mechanisms due to anthropogenic habituation (İ1). While stakeholders (100%, 95% CI: 98.1–100%) perceive the tortoises as cultural symbols of abundance, the biological reality indicates severe welfare risks, including potential metabolic bone disease from a monotonous anthropogenic diet and a disrupted Ca:P ratio. The site is categorized as a ‘High-Constraint Interaction Zone’. We propose a management transition toward a monitored ‘Urban Wildlife Education Station’ to align local cultural values with international animal welfare and conservation standards. Full article

Nucleoside diphosphate kinase (NDPK) is a ubiquitous enzyme that maintains cellular nucleotide balance by catalyzing the transfer of phosphate groups between nucleoside diphosphates and triphosphates. Although the evolutionary conservation of NDPK is well established, several aspects of its diversification and functional adaptation remain unclear. The central question of this work is how NDPK evolved across plant species, focusing on the Solanaceae family and how its evolutionary history relates to the diversification of its cellular functions. Phylogenetic and molecular dating analyses showed that the division between NDPK groups 1 and 2 predates the divergence of plants and animals, whereas plant-specific NDPK types (I–IV) originated early in streptophyte evolution. Solanaceae species retain a conserved set of NDPK genes, including a type III isoform with features consistent with mitochondrial targeting. Functional assays in isolated potato tuber mitochondria revealed high NDPK activity in the intermembrane space, sustaining ADP supply to oxidative phosphorylation. Activation of mitochondrial NDPK induced a phosphorylative respiratory state, which partially dissipated the mitochondrial membrane potential and significantly reduced reactive oxygen species (ROS) production. GDP and UDP were preferentially phosphorylated, conferring a stronger antioxidant effect than other nucleotides. Consistently, the mitochondrial isoform StNDPK3 was upregulated during tuber development. Together, our results demonstrate that NDPKs are evolutionarily conserved yet functionally diversified enzymes in plants and identify mitochondrial NDPK as a key modulator of mitochondrial redox homeostasis. By linking nucleotide metabolism to Δψ_m control and ROS suppression, this study highlights a previously underappreciated antioxidant mechanism that integrates mitochondrial energy metabolism with developmental and stress-related processes in plants. Full article

Industrialization has caused extensive environmental change, including a global surge in plastic production and pollution. This has resulted in the accumulation of microplastics (MPs; <5 mm) and nanoplastics (NPs; <1 μm) in ecosystems worldwide. MPs originate from both primary sources, such as cosmetics and industrial applications, and secondary sources, through the degradation of larger plastic debris. As a result, MPs and NPs have become ubiquitous contaminants, posing significant toxicological risks to living organisms. These persistent pollutants are diverse polymers that vary in size, shape, and chemical composition, making their impacts on organism physiology complex and difficult to disentangle. Plastic pollution is particularly severe in aquatic environments, where particles accumulate from terrestrial sources such as urban dust, agricultural runoff, industrial discharges, and wastewater effluents. Although most research has centered on marine ecosystems, emerging evidence indicates that freshwater environments may contain comparable or even higher concentrations of MPs. Once inside the body, MPs can translocate into tissues and exert toxic effects on multiple organ systems. Collectively, plastic pollution poses not only physiological but also neurological and behavioral risks to aquatic life, with potential consequences for ecosystem stability and trophic interactions. Both MPs and NPs are sufficiently small to cross the blood–brain barrier, raising concerns about their potential impacts on the nervous system by interfering with neuronal function and brain development. Plastic particles can accumulate in neural tissues, inducing oxidative stress, neuroinflammation, and disruption of neurotransmitter signaling. Such neurotoxic effects are linked to altered locomotion, feeding, predator avoidance, and social behaviors across multiple species. This review examines current evidence on the neurotoxic effects of plastic pollution in aquatic organisms and underscores the urgent need for further research and action to mitigate its impact. In light of escalating plastic production and inadequate waste management, the growing evidence that MPs and NPs disrupt aquatic nervous systems, behavior, and ecosystem stability underscores an urgent need for intensified research, improved mitigation strategies, particularly for nanoplastics, and the accelerated development of truly safe and sustainable alternatives. Full article

The European green crab (Carcinus maenas) is an intertidal crustacean that has extended its invasive range globally and is regarded as a major pest species for bivalves, impacting coastal food chains and aquacultures. Crabs primarily use chemosensory cues to sense their environment for feeding to avoid predation and to locate mates and induce mating. Consequently, known attractants including food baits are frequently employed in trapping and control efforts. Here, we investigate the effects of introducing a predatory fish odour to the environment and show that it elicits anti-predator behaviour in C. maenas. A 45% reduction in crab foraging and feeding behaviour was observed when predator odour was introduced compared with food control experiments. A further 23% reduction (68% reduction overall) in feeding behaviour was observed after crabs were exposed to (though housed separately from) the same seawater as the live predator for several days. This highlights the increased awareness or continuous stress of these habituated crabs towards predator odour. This study also presents potential for application as a deterrent in integrated pest management strategies for this global invader. Full article

Between 2014 and 2023, Italian Manila clam (Ruditapes philippinarum) production declined by 36% due to climate change and predation by the invasive blue crab (Callinectes sapidus), which preys particularly on small clams. Traditionally, Manila clam farming starts with seed collection from natural recruitment or hatcheries, followed by pre-fattening in raceways and/or FLUPSY (Floating Upweller Systems) to size T3 (>3 mm). The fattening phase in lagoons up to the commercial size (>25 mm) follows. Rearing juveniles in controlled conditions may ensure stable supplies of high-quality seed, reduced mortality, and increase overall yields. Furthermore, a larger pre-seeding size (e.g., T10, >10 mm) is supposed to improve resistance to predators and environmental stress. This study uses an ex-ante Life Cycle Assessment (LCA) to evaluate the potential environmental impacts of a novel and unique “sand-nursery” method under development at an Italian company. The nutrient removal potential of juvenile clams was also assessed as an ecosystem service. At full capacity, the optimised system could produce 120 t of liveweight juveniles and remove 338 kg of nitrogen and 32 kg of phosphorus. Although it has inherent limitations, the ex-ante LCA results show that electricity consumption is the main contributor to environmental impacts, with a global warming potential of 1.11 kg CO₂ eq/kg T10 clam. Further research is needed to assess impacts across the full production cycle. Full article

Plants defend against pathogens such as fungi by initiating coordinated structural and chemical responses. Pathogen perception triggers rapid cytosolic calcium influx and calcium oscillations that drive defense gene expression, yet the mechanisms by which these signals encode stressor intensity and propagate systematically remain unclear. Here, we present a microfluidic system to characterize intracellular calcium dynamics in protonemal colonies of the moss Physcomitrium patens (Hedw.) upon precise and reversible exposure to fungal chitin oligosaccharides. Epifluorescent imaging of cells expressing the calcium indicator GCaMP6f revealed a rapid, coordinated calcium response to chitin addition, followed by stereotyped oscillations that subsided quickly upon stimulus removal. We implemented an unbiased image segmentation algorithm using pixel-based k-means clustering to automatically locate regions with specific oscillatory signatures. Calcium dynamics were distinct across adjacent cells, distinguishable by cell type, and significantly modulated by circadian rhythm, adaptation time within the device, and stimulus timing. Cytosolic calcium oscillations, which rose and fell symmetrically within about 60 s, occurred spontaneously during the subjective night and following short adaptation periods. Chitin elicited strong oscillations with increased frequency, amplitude, and duration, and repeated pulses entrained regular, colony-wide oscillations at the stimulation interval. This study complements prior investigations of whole plant and growth tip dynamics and provides a quantitative framework to study calcium signaling in plants, including mechanisms of signal propagation and the role of oscillation frequency on gene expression. Full article

Heavy metals (HMs) and metal-oxide nanoparticles (NPs) frequently co-occur in freshwater systems, yet their combined effects on microbial predators remain poorly understood. Here, the freshwater ciliate Coleps hirtus was used to evaluate the cytotoxicity of single and binary mixtures of HMs (Cd, Cu, Zn) and NPs (ZnO, CuO, TiO₂, SiO₂), and to characterize associated antioxidant responses. Acute toxicity was assessed after 24 h by estimating LC₂₀ and LC₅₀ values, while mixture toxicity for Cd + Zn and Cd + ZnO was analyzed using the Toxic Unit approach and the MixTOX framework. Non-enzymatic (TPC, DPPH, HRSA) and enzymatic (CAT, GST, GPx, SOD) antioxidants were quantified as sublethal biomarkers at concentrations below lethal thresholds. HMs were markedly more toxic than NPs, with a toxicity ranking of Cu > Cd >> Zn, whereas NPs followed ZnO > CuO >> TiO₂ >> SiO₂. Cd + Zn mixtures showed predominantly antagonistic or non-interactive effects, while Cd + ZnO mixtures exhibited strong synergistic toxicity with a non-linear dependence on mixture composition, as supported by MixTox modeling. Exposure to HMs and NPs induced significant and often coordinated changes in antioxidant biomarkers, with binary mixtures eliciting stronger responses than single contaminants. Together, these findings indicate that mixture composition strongly influences both toxicity outcomes and oxidative stress responses in C. hirtus. The combination of clear, mixture-dependent toxicity patterns and robust oxidative stress responses makes C. hirtus a promising bioindicator for freshwater environments impacted by HMs and NPs. Full article

Insect pollination, a critical ecological process, pre-dates the emergence of angiosperms by nearly 200 million years, with fossil evidence indicating pollination interactions between insects and non-angiosperm seed plants during the Late Paleozoic. This review examines the symbiotic relationships between insects and gymnosperms in pre-angiosperm ecosystems, highlighting the complexity of these interactions. Fossil records suggest that the mutualistic relationships between insects and gymnosperms, which facilitated plant reproduction, were as intricate and diverse as the modern interactions between angiosperms and their pollinators, particularly bees. These early pollination systems likely involved specialized behaviors and plant adaptations, reflecting a sophisticated evolutionary dynamic long before the advent of flowering plants. The Anthropocene presents a dichotomy: while climate change and anthropogenic pressures threaten insect biodiversity and risk disrupting angiosperm reproduction, such upheaval may simultaneously generate opportunities for novel plant–insect interactions as ecological niches are vacated. Understanding the deep evolutionary history of pollination offers critical insight into the mechanisms underlying the resilience and adaptability of these mutualisms. The evolutionary trajectory of bees—originating from predatory wasps, diversifying alongside angiosperms, and reorganizing after mass extinctions—exemplifies this dynamic, demonstrating how pollination networks persist and reorganize under environmental stress and underscoring the enduring health, resilience, and adaptability of these essential ecological systems. Full article

The impact of tourism on Magellanic penguins (Spheniscus magellanicus) in Patagonia is a complex issue that requires a balanced approach between conservation and sustainable tourism development. While tourism in the region can bring significant economic benefits, it can also have a negative impact on the penguins by disrupting nesting behavior and chick rearing, and even increasing the risk of disease and predation. We examined a comparative analysis of scientific papers on the impact of tourism on Magellanic penguins in two breeding colonies in Argentinean Patagonia, which have been visited for 10 to 50 years and whose visitor numbers range from 10,000 to 120,000 per year. We analyzed different physiological parameters (i.e., immunological, hematological, biochemical, and stress parameters) and behavioral respond (alternate head turns) in adult birds and chicks in these colonies. Although the results suggest that Magellanic penguins have adapted well to the presence of tourists in their breeding colonies, we documented changes in certain physiological parameters that indicate chronic stress due to high exposure to tourism. It is important to promote sustainable tourism in Patagonia that not only minimizes these negative impacts but also improves the protection of the penguins and their habitat. This includes the creation of new nature reserves, environmental education, and the regulation of tourism activities. Implementing responsible tourism practices can ensure economic benefits while protecting the well-being and health of penguin populations. The combination of increased tourist awareness and concrete conservation measures can protect not only the Magellanic penguins but also the natural wealth of the entire Patagonia region. Full article

Animals scan their environment to detect threats. Such vigilance behaviour is costly, and animals adjust their vigilance to prevailing threats. Waterholes are dangerous places that attract predators, and require heightened vigilance. We investigated how Gouldian finches adjust their vigilance at waterholes by measuring the frequency of head movements and interscan interval while drinking. The frequency of head movements increased with increasing risk perception (a) from perching in the tree to being on the ground and (b) while drinking, with a higher frequency of movements recorded at small waterholes compared to medium and large ones. The latter adds to recent findings that small waterholes are perceived as more dangerous and require further investigation. With a predicted increase in droughts, birds will rely on small waterholes for longer during the dry season which might cause stress. Furthermore, interscan interval varied in terms of interaction with waterhole size and group size, indicating adjustments linked to perceived threat and social effects. Finally, frequency of head movements and interscan intervals were positively correlated. This might reflect different strategies to check the environment, with either a high frequency of head movements when scanning accompanied by long drinking bouts or looking in one direction for a longer time (lower vigilance) but repeating this behaviour at shorter intervals. Full article

Microplastics represent an emerging threat to aquatic environments and organisms, as they infiltrate water systems, are ingested by marine species, and cause physical harm, endocrine disruption, and bioaccumulation up the food chain, potentially impacting biodiversity and human health. Aquatic ecosystems face considerable harm from microplastic pollution because fish in the early developmental stages, including embryos, larvae, and juveniles, are more susceptible due to their immature physiological and detoxification systems. This review aims to comprehensively explore the impacts of microplastics on the early life stages of fish. Aquatic environments receive primary and secondary MPs from urban runoff and industrial waste, together with degraded plastics, which affect fish embryos and larvae via direct ingestion, surface adhesion, and trophic transmission pathways. The physical impact of MPs causes digestive tract blockages that reduce hatching success and create developmental problems in fish organs, but chemical toxicity develops from plasticizers, heavy metal leaching, and pollutant adsorption, which causes oxidative stress, endocrine disruption, and metabolic dysfunction. Survival rates decrease because exposure causes fish to perform poorly during swimming activities and make limited efforts to avoid predators. The small dimensions and high chemical reactivity of MPs increase their bioavailability, which promotes tissue penetration and leads to accumulation at different levels of the food chain. This comprehensive review emphasizes that we need to establish uniform detection protocols, long-term exposure research, and effective strategies to control MP pollution. The resolution of these difficulties remains essential for protecting fish populations, as well as for protecting biodiversity and minimizing seafood contamination risks to human health. Full article

Recent studies indicated a connection between trace amine-associated receptor 5 (TAAR5) and emotional behaviors related to anxiety and depression; however, the neurobiological basis of this link is still unclear. Using mutant TAAR5 knockout (TAAR5-KO) mice, we explored the consequences of receptor deletion on dopamine (DA) dynamics in the ventral striatum and stress-related behaviors. Voltammetric measurements of DA in the nucleus accumbens (NAc) coupled with electrical stimulation of the ventral tegmental area (VTA) revealed that mice lacking TAAR5 display a greater DA release, while its reuptake is not affected. Behaviorally, mutants were significantly less anxious in the elevated plus maze (EPM) and consumed more sucrose in comparison with wild-type (WT) controls. The new object recognition test (NOR) did not uncover a difference between these genotypes. During predator (rat) stress exposure, mutant and WT mice showed quite distinct responses versus the behavior observed in stressless conditions. Control animals demonstrated a substantial increase in “freezing” (a sign of passive coping), while “running” and “exploring” patterns (signs of active coping) were significantly extended in mice lacking TAAR5. Short-term consequences of stress were explored 24 h following the predator exposure. The absence of TAAR5 did not prevent or reduce stress-induced anxiety in the EPM. In fact, the level of anxiety in mutants reached that observed in control mice. Furthermore, activity in NOR was significantly decreased in mice lacking TAAR5 but not in WT animals. On the other hand, predator exposure resulted in impaired NOR in the WT control, whereas mutants’ performance was not altered. These findings indicate that TAAR5 deletion leads to significant DA imbalance, which might at least partly explain the better stress-coping strategy and other stress-induced behavioral consequences observed in mutant animals. Full article

Light is a fundamental ecological cue for insects, influencing physiological rhythms and behavior. We investigated how varying light intensities affect locomotion and foraging in H. axyridis color morphs, and examined the role of visual opsins. Three adult female morphs were assayed under white light at 1000, 5000, and 10,000 lx. Higher light intensity significantly elevated body temperature and locomotor activity across morphs, with the inherently dark f. conspicua morph exhibiting the greatest increases. Predation rates on pea aphids trended upward with intensity but differed significantly by morph: f. conspicua beetles consistently consumed more prey than f. succinea. RNAi knockdown of the UV-sensitive opsin HaUVSop-2 significantly reduced the crawling distance of satiated beetles under 5000 lux white light. Correspondingly, supplementation of white light with blue light (short wave) enhanced movement, whereas red supplementation increased aphid consumption. These results suggest that Short-wavelength light has the potential to stimulate the dispersal of ladybirds, whereas long-wavelength light may enhance predation on prey by increasing microenvironment temperature or improving prey recognition. We conclude that light intensity and spectrum jointly modulate H. axyridis behavior in a morph-dependent manner, mediated in part by visual opsins. Melanic morphs leverage thermal melanism to gain higher activity under bright light, implying an evolved trade-off between dispersal and stress tolerance. Our findings have practical implications: tailored lighting (e.g., blue-enhanced illumination to stimulate predation and dispersal of H. axyridis) could improve biological control efficacy in agroecosystems. Full article

Although the health risks associated with exposure to potentially harmful elements (PHEs) are well documented, there is still limited research on their accumulation at trace concentrations in small mammals inhabiting agricultural ecosystems. This study provides the first comprehensive assessment of PHE accumulation in fossorial water voles (Arvicola scherman) from two low-input apple orchards (Nava and Oles) located in Asturias, northwestern Spain, demonstrating its value as a potential bioindicator of trace element inputs. We quantified the concentrations of three toxic metals (Pb, Cd, and Hg) and selenium (Se), an element with concentration-dependent toxicity, in kidney, liver, and muscle tissues. We also determined inter-population differences and associations with body condition. Overall, element concentrations generally reflected the natural content of the local soils, except for Cd in the kidney, which exceeded soil levels, highlighting its strong affinity for this organ. Significant differences in Pb, Cd, and Se accumulation were found among tissues, with the kidney showing the highest levels, underscoring the importance of organ-specific monitoring. The observed positive correlations between body condition and Se and Cd in kidney tissue, and Cd in liver tissue, particularly in the Nava population, suggest that individual health status modulates exposure and accumulation dynamics. Higher PHE burdens were found in Oles specimens, pointing to a potential threshold effect where higher contamination may begin to impair physiological condition. In contrast, Hg showed a negative relationship with body condition, suggesting possible adverse effects even in these low-input systems. These findings highlight the importance of carefully interpreting physiological biomarkers within an ecological context and demonstrate the potential for trace elements to propagate through the food web, with possible cascading effects on predator health and key ecosystem services, such as natural pest control. Future research should extend to more contaminated sites and adopt an integrative framework combining biomonitoring, dietary ecology, and stress physiology to better assess the ecological risks posed by trace elements in agroecosystems. Full article