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Rodent migraine models have been developed to study the underlying molecular mechanisms of migraine, but these need further development and validation to stay relevant. The glyceryl trinitrate (GTN) mouse model with tactile hypersensitivity as the primary readout, has been highly used to understand the pathophysiology of migraine. Nevertheless, this readout has questionable translatability to the experience of spontaneous pain and additional readouts are needed to improve this model. We explored the applicability of several spontaneous behaviours and burrowing activity as additional markers to detect effects of repeated GTN injections in mice. We used the Laboratory Animal Behaviour Observation Registration and Analysis System (LABORAS) test system to understand the potential effect of GTN on locomotion and other behavioral parameters in two different experiments. Burrowing was used to investigate the potential effect on GTN on a voluntary innate behavior of mice. We found no clear effect of GTN on either locomotion or burrowing in these experiments. With our experimental design, there was no significant difference between GTN and vehicle and neither locomotion nor burrowing activity will readily supplement the von Frey test. The search for additional none-evoked markers of pain in rodent migraine models will continue. [ABSTRACT FROM AUTHOR]

Strong selective pressure on phenotype can arise when habitat transitions fundamentally alter the physical media in which animals live, such as the invasion of land by lobe-finned fishes and insects. When environmental gradients differ drastically among habitats and multiple lineages transition between these habitats, we expect phenotypic convergence to be prevalent. One transition where widespread convergence has been observed is the shift from aboveground to subterranean environments in fossorial animals. Subterranean environments are low-light, confined spaces and tend to be hypoxic or anoxic, not to mention that the act of burrowing itself demands morphological specializations for excavation. Research suggests burrowing promotes morphological convergence in crayfish, with non-burrowing forms having a dorsoventrally compressed carapace and long, slender claws (chelae), while primary burrowing forms have a dorsolaterally compressed carapace and shorter, more powerful claws. However, earlier ecomorphological comparisons relied on qualitative rather than quantitative assessments of phenotypic differences. This study tested for convergence in North American crayfishes using a geometric morphometric approach. We photographed the carapace and claw for representative species across 13 North American genera. We hypothesized that crayfishes that occur in similar habitats and exhibit similar burrowing behaviors, would converge in their carapace and claw shapes. We found evidence for convergence in carapace and claw morphologies in burrowing crayfishes. However, claw phenotypes did not converge as strongly as carapace shape, an example of "imperfect" or "incomplete" convergence we attribute to the multiple competing demands on claw form and function. We argue that nuances in habitat characteristics, like soil type or compaction, make complete convergence unlikely for range- and dispersal-limited fossorial crayfishes. [ABSTRACT FROM AUTHOR]

Due to the building of the Yangtze River Water Conservancy Project, the study of the changing characteristics of intertidal sediments and their interaction with benthic species along the north shore of Hangzhou Bay is vital. In this study, Macrophthalmus abbreviatus and Macrophthalmus banzai were selected to compare the significance of differences in the nature of their substrates and to analyse their preferences for different substrate conditions through indoor experiments. This reveals the effect of sediment grain size on the feeding and burrowing behaviour of both. PCA and test for significance of differences in morphological parameters between the two species showed that the morphological differences between the two species were focused on the cephalothorax width-to-length and height-to-width ratios as well as the height-to-width and height-to-length ratios of the ambulatory legs, which were significant (P < 0.05), specifically, the Macrophthalmus abbreviatus had a flatter and narrower cephalothorax and sharper ambulatory legs, which were optimised for burrowing in a high- compaction substrate. Macrophthalmus banzai, on the other hand, with its broader cephalothorax and stouter ambulatory legs, was better adapted to burrowing behaviour in a low-compaction substrate. Their tilting burrowing habits and variances in burrow angle and fit to the body also reflect adaptations to the nature of the substrate in their distinct habitats. The effects of sediment particle size changes on the two species were deduced. The changes of the two species populations caused by the change of sediment particle size in the north shore of Hangzhou Bay in recent years were analyzed. This paper emphasises that substrate tightness is an important factor driving habitat selection for both crab species, and therefore long-term monitoring of estuarine sediment grain size and benthic fauna is important for assessing anthropogenic impacts on intertidal ecosystems. [ABSTRACT FROM AUTHOR]

Accurate information on species range contraction is the cornerstone of effective biodiversity conservation. The eastern indigo snake (Drymarchon couperi) is an apex predator in Florida and, similar to many species native to Florida, is threatened by widespread habitat destruction. Environmental deoxyribonucleic acid (eDNA) monitoring of this elusive snake would provide a non‐invasive approach to improve our knowledge of the species' range and distribution. We designed and tested an eDNA assay that can detect the presence of D. couperi from soil samples from their natural scrub habitat in Florida. We validated our assay in silico, in vitro, and in situ. Furthermore, we investigated the influence of temperature and humidity on the degradation rate of eDNA over time. We successfully amplified the cytochrome b gene for D. couperi at concentrations as low as 3 × 10−3 ng/μL and successfully detected the presence of D. couperi in 2 of 30 in situ field soil samples. The degradation experiment resulted in detectable DNA for 10 days. Interestingly, temperature and humidity had no effect on the degradation rate of eDNA in our experimental conditions. This study provides support for soil eDNA applications to detect the presence of a federally threatened species in their natural environment bolstering our ability to monitor the conservation and management of imperiled species. Environmental DNA provides an additional conservation tool to quickly and effectively monitor species range shifts driven by multiple anthropogenic stressors to promote the persistence of imperiled species. [ABSTRACT FROM AUTHOR]

This article discusses the phenomenon of freshwater macroinvertebrates, specifically the midge Axarus, boring into rock and hard substrates in aquatic ecosystems. While burrowing into softer sediments is well-documented, the behavior of burrowing into rock and hardpan habitats is less understood. The article presents observations of Axarus populations in Lake McMurtry, Oklahoma, where the larvae were found to create burrows in clay and sandstone habitats. The study also highlights the presence of other invertebrates and parasites associated with the burrows. The authors emphasize the need for further research on rock-boring macroinvertebrates and their ecological impacts. [Extracted from the article]

Access to subterranean refugia, such as animal burrows, can affect the ecology and life history of wildlife in an array of habitat types. Subterranean refugia are commonly used for thermal refuge, for shelter from predators, or as suitable locations for nesting and/or brooding offspring; because of this, refugia can potentially impact rates of survivorship and recruitment. In southwestern Florida, Burmese pythons (Python bivittatus), an established and highly impactful invasive species, have been observed using subterranean refugia on numerous occasions. Because python management is an utmost priority in Florida, understanding the potential implications of this behavior is key to mitigating python impacts on native wildlife. We used 29 radio-telemetered Burmese pythons to investigate the extent to which pythons used subterranean refugia in the southwestern portion of their Florida range. We explored spatiotemporal patterns of refuge use and quantitatively assessed how python sex, reproductive season, and habitat type affected the probability of using different types of refugia. We observed pythons using four types of refugia, including Gopher Tortoise burrows, Nine-banded Armadillo burrows, and natural and anthropogenic ground-based cavities. Pythons used these refugia for seeking thermal refuge, aggregating, breeding, and nest brooding, and they were most likely to use refugia during their breeding and nesting seasons. Nine python nests, representing 71% of those discovered during the study, were oviposited and brooded in Gopher Tortoise or Nine-banded Armadillo burrows. Implications of this behavior warrant further assessment and incorporation into management strategies as they may affect Burmese python recruitment, survival, and dispersal. [ABSTRACT FROM AUTHOR]

Simple Summary: Xyleborus beetles are tiny insects that impact forests and agriculture. These beetles burrow into trees and crops, causing damage that affects both the environment and the economy. This review aims to provide a clear understanding of the biology and behavior of Xyleborus beetles, including their life cycle, habitat, and feeding habits. We also discuss the various methods currently used to manage and control these pests, such as chemical treatments, biological controls, and integrated pest management strategies. By highlighting recent scientific advancements and identifying future research needs, this review offers insights for researchers, farmers, and policymakers. Understanding and effectively managing Xyleborus beetles is crucial for protecting our forests and agricultural resources, ultimately benefiting society by reducing economic losses and preserving ecological balance. Xyleborus beetles, a diverse group of ambrosia beetles, present challenges to forestry and agriculture due to their damaging burrowing behavior and symbiotic relationships with fungi. This review synthesizes current knowledge on the biology, ecology, and management of Xyleborus. We explore the beetles' life cycle, reproductive strategies, habitat preferences, and feeding habits, emphasizing their ecological and economic impacts. Control and management strategies, including preventive measures, chemical and biological control, and integrated pest management (IPM), are critically evaluated. Recent advances in molecular genetics and behavioral studies offer insights into genetic diversity, population structure, and host selection mechanisms. Despite progress, managing Xyleborus effectively remains challenging. This review identifies future research needs and highlights innovative control methods, such as biopesticides and pheromone-based trapping systems. [ABSTRACT FROM AUTHOR]

The extended phenotype of helical burrowing behavior in animals has evolved independently many times since the Cambrian explosion (~540 million years ago [MYA]). A number of hypotheses have been proposed to explain the evolution of helical burrowing in certain taxa, but no study has searched for a general explanation encompassing all taxa. We reviewed helical burrowing in both extant and extinct animals and from the trace fossil record and compiled 10 hypotheses for why animals construct helical burrows, including our own ideas. Of these, six are post‐construction hypotheses—benefits to the creator or offspring, realized after burrow construction—and four are construction hypotheses reflecting direct benefits to the creator during construction. We examine the fit of these hypotheses to a total of 21 extant taxa and ichnotaxa representing 59–184 possible species. Only two hypotheses, antipredator and biomechanical advantage, cannot be rejected for any species (possible in 100% of taxa), but six of the hypotheses cannot be rejected for most species (possible in 86%–100% of taxa): microclimate buffer, reduced falling sediment (soil), anticrowding, and vertical patch. Four of these six are construction hypotheses, raising the possibility that helical burrowing may have evolved without providing post‐construction benefits. Our analysis shows that increased drainage, deposit feeding, microbial farming, and offspring escape cannot explain helical burrowing behavior in the majority of taxa (5%–48%). Overall, the evidence does not support a general explanation for the evolution of helical burrowing in animals. The function and evolution of the helix as an extended phenotype seems to provide different advantages for different taxa in different environments under different physicochemical controls (some traces/tracemakers are discussed in more detail due to their association with body fossils and well‐constrained physicochemical parameters). Although direct tests of many of the hypotheses would be difficult, we nevertheless offer ways to test some of the hypotheses for selected taxa. [ABSTRACT FROM AUTHOR]

Muddy marine sediments are elastic materials in which bubbles grow and worms extend their burrows by fracture. Bubble growth and burrowing behavior are dependent on the stiffness and fracture toughness (KIc) of these muds. This article describes a custom laboratory apparatus to measure the fracture toughness of muddy, cohesive sediments using a bubble injection method. The system induces fracture in sediment samples by incrementally injecting air through a needle inserted into the sediment. The increasing pneumatic pressure is monitored until it drops abruptly, indicating bubble formation. Fracture toughness is then calculated from the peak pressure at which fracture occurred, following cavitation rheology methods developed for soft gels. The system has produced measurements that compare well to previous data but with better spatial resolution, allowing for characterization of spatial heterogeneity on small scales. [ABSTRACT FROM AUTHOR]

The relationship between pangolin-CoV and SARS-CoV-2 has been a subject of debate. Further evidence of a special relationship between the two viruses can be found by the fact that all known COVID-19 viruses have an abnormally hard outer shell (low M disorder, i.e., low content of intrinsically disordered residues in the membrane (M) protein) that so far has been found in CoVs associated with burrowing animals, such as rabbits and pangolins, in which transmission involves virus remaining in buried feces for a long time. While a hard outer shell is necessary for viral survival, a harder inner shell could also help. For this reason, the N disorder range of pangolin-CoVs, not bat-CoVs, more closely matches that of SARS-CoV-2, especially when Omicron is included. The low N disorder (i.e., low content of intrinsically disordered residues in the nucleocapsid (N) protein), first observed in pangolin-CoV-2017 and later in Omicron, is associated with attenuation according to the Shell-Disorder Model. Our experimental study revealed that pangolin-CoV-2017 and SARS-CoV-2 Omicron (XBB.1.16 subvariant) show similar attenuations with respect to viral growth and plaque formation. Subtle differences have been observed that are consistent with disorder-centric computational analysis. [ABSTRACT FROM AUTHOR]

The evolutionary rise of powerful new ecosystem engineering impacts is thought to have played an important role in driving waves of biospheric change across the Ediacaran–Cambrian transition (ECT; c. 574–538 Ma). Among the most heavily cited of these is bioturbation (organism‐driven sediment disturbance) as these activities have been shown to have critical downstream geobiological impacts. In this regard priapulid worms are crucial; trace fossils thought to have been left by priapulan‐grade animals are now recognized as appearing shortly before the base of the Cambrian and represent some of the earliest examples of bed‐penetrative bioturbation. Understanding the ecosystem engineering impacts of priapulids may thus be key to reconstructing drivers of the ECT. However, priapulids are rare in modern benthic ecosystems, and thus comparatively little is known about the behaviours and impacts associated with their burrowing. Here, we present the early results of neoichnological experiments focused on understanding the ecosystem engineering impacts of priapulid worms. We observe for the first time a variety of new burrowing behaviours (including the formation of linked burrow networks and long in‐burrow residence times) hinting at larger ecosystem engineering impacts in this group than previously thought. Finally, we identify means by which these results may contribute to our understanding of tracemakers across the ECT, and the role they may have had in shaping the latest Ediacaran and earliest Cambrian biosphere. [ABSTRACT FROM AUTHOR]

A prevailing animal model currently used to study severe human diseases like obstructive cholestasis, primary biliary or sclerosing cholangitis, biliary atresia, and acute liver injury is the common bile duct ligation (cBDL). Modifications of this model include ligation of the left hepatic bile duct (pBDL) or ligation of the left bile duct with the corresponding left hepatic artery (pBDL+pAL). Both modifications induce cholestasis only in the left liver lobe. After induction of total or partial cholestasis in mice, the well-being of these animals was evaluated by assessing burrowing behavior, body weight, and a distress score. To compare the pathological features of these animal models, plasma levels of liver enzymes, bile acids, bilirubin, and within the liver tissue, necrosis, fibrosis, inflammation, as well as expression of genes involved in the synthesis or transport of bile acids were assessed. The survival rate of the animals and their well-being was comparable between pBDL+pAL and pBDL. However, surgical intervention by pBDL+pAL caused confluent necrosis and collagen depositions at the edge of necrotic tissue, whereas pBDL caused focal necrosis and fibrosis in between portal areas. Interestingly, pBDL animals had a higher survival rate and their well-being was significantly improved compared to cBDL animals. On day 14 after cBDL liver aspartate, as well as alanine aminotransferase, alkaline phosphatase, glutamate dehydrogenase, bile acids, and bilirubin were significantly elevated, but only glutamate dehydrogenase activity was increased after pBDL. Thus, pBDL may be primarily used to evaluate local features such as inflammation and fibrosis or regulation of genes involved in bile acid synthesis or transport but does not allow to study all systemic features of cholestasis. The pBDL model also has the advantage that fewer mice are needed, because of its high survival rate, and that the well-being of the animals is improved compared to the cBDL animal model. [ABSTRACT FROM AUTHOR]

Introduction: The macrobenthos are crucial for the stability of estuarine ecosystems due to their burrowing behavior in the sediment and their uptake of nutrients from plants. These activities lead to significant alterations in both the morphological and biogeochemical processes within the region. Methods: However, there is limited investigation into carbon cycling processes specifically related to crab bioturbation. Additionally, few studies have examined enzymatic activities and carbon fractions in sediments from crab burrow walls at different crab growth stages. This study aims to explore the impact of both plant invasiveness and crab bioturbation on carbon storage. Results: Our findings suggest that plant invasion leads to higher organic accumulation due to the reduction of recalcitrant organic carbon (ROC) (decreased by 11.6% in invasive and 62.6% in native site from April to December), faster photosynthetic rates (25.8 μmol/m² s in invasive and 10.7 μmol/m² s in native site), and an increased presence of arbuscular mycorrhizal fungi (AMF) in the soil over time. However, the increase of easy oxidized carbon (EOC) may lead to less carbon storage in soil (increase by 67.7% in invasive and 48.8% in native site from April to December). In addition to invasiveness, the bioturbation activities of macrobenthos also affect carbon storage. Sediments from crab burrows exhibit higher EOC content (33.6% more than the bulk soil) and higher levels of carbon cycling-related enzymes, including S-ACT, S-β-GC, and S-ACP activities (24.2%, 8.99%, and 135.6% higher than the bulk soil, respectively). Discussion: These changes contribute to reduced carbon accumulation in the soil. Therefore, crab bioturbation is a more significant factor affecting carbon sink capacity than plant invasion. [ABSTRACT FROM AUTHOR]

Gopher tortoises (Gopherus polyphemus), the only land tortoises native to the southeastern United States, are found throughout their range in a variety of upland habitat types, with their use of upland pine-dominated habitats receiving most attention. Fewer studies have examined their use of coastal beach dune habitats, but some of the highest gopher tortoise burrow densities have been observed in this vulnerable, yet critical, habitat. Gopher tortoises construct extensive burrows for their own use, and these burrows have also been shown to support numerous other animals (i.e., commensal species) that may depend on them for critical needs (e.g., shelter, food). Motion-activated wildlife cameras allow for nonintrusive and continuous observation of burrow activity with minimal disturbance to the animals and habitat. Here we examined 10 gopher tortoise burrows over a 12-mo period using motion-activated wildlife cameras in beach dune habitat in an undeveloped section of coastline in northeast Florida. Gopher tortoises were most frequently observed during the spring and summer months (April–August), and most often during daylight hours. Gopher tortoise behaviors such as burrow maintenance, mating, foraging, and resting were all observed more during April through August, which is a slightly earlier start than these activities have been observed in inland populations. We observed a commensal community of 51 animal taxa using tortoise burrows and their aprons, 29 of which we were able to identify to species. The commensal community was generally similar to those in inland habitats, but we did observe some taxa that were previously undocumented at gopher tortoise burrows including 2 bird species and 8 insect taxa. These commensals displayed varied diel and seasonal activity patterns, with many taxa observed at burrows concurrently occupied by gopher tortoises. Considered together, our observations of gopher tortoise behavior and their commensal community in coastal beach dunes provide valuable insights into the importance of this understudied habitat and highlight distinct differences from inland ecosystems. [ABSTRACT FROM AUTHOR]

Cigarette butts (CBs) are non-biodegradable harmful residues of synthetic origin and are widespread in marine environments around the world. Although environmental factors are often primarily responsible for the fragmentation of microplastics in the marine environment, biotic factors have recently been shown to be equally important in plastic debris. This study evaluates the role of the Hediste diversicolor polychaete in the fragmentation of CBs in the marine environment. Polychaetes were exposed to three concentrations of CB (0 (as the control), 0.25, and 1 butt L−1) at two different temperatures (15 °C and 23 °C) for 28 days. At each temperature, aquaria without polychaetes were used to study the effect of the burrowing activity of the polychaete on CB fragmentation. Toxicants analysed from exposed sediments increased their concentration in a dose-dependent manner to the CB concentration at a temperature of 15 °C but not at 23 °C. CBs did not directly decrease Hediste survival, but prolonged elevated temperatures increased the polychaetes' susceptibility. The negative effects of CBs on burial success and burrowing behaviour could not be offset by the reduced start time caused by elevated temperatures. Regardless of temperature, both the weight loss and physical fragmentation of CBs buried in polychaete-contaminated sediments were significantly higher than those without Hediste, with no differences between the two concentrations tested. FTIR-ATR analysis used to evaluate CB degradation in relation to cellulose acetate decomposition showed a greater degradation of this compound in treatments with Hediste than in those without polychaetes (~2.75 times), but these differences were not significant. This study is a promising initial step for future research, as any factor that facilitates the fragmentation of this prevalent and hazardous waste must be carefully studied to extract the maximum benefit to help to reduce CBs in the marine environment. [ABSTRACT FROM AUTHOR]

Biological invasions cause huge environmental and socio-economic losses worldwide. Among successful invaders, there are also several decapod crustacean species. In this study, we report the presence of an potentially invasive crab species that damages rice crops in Sumatra, Indonesia. This paddy-field crab Parathelphusa convexa De Man, 1879 is a freshwater species native to Java, which was introduced in Sumatra around 2000 via an uncertain pathway. The sampling was conducted from July to September 2021 in paddy fields in West Sumatra, where its well-established population was discovered. The crab negatively impacts rice plants and paddy fields in the region through grazing and burrowing behaviour. Since the species is too small to be attractive for human consumption and also, it is not popular for ornamental keeping due to indistinct colouration, it has no benefits for local communities and is considered unwanted. The continuous monitoring of the species with possible regulation or eradication activity in Sumatra is recommended. [ABSTRACT FROM AUTHOR]

Environmental heterogeneity shapes the traits of natural populations, including space use and burrowing behavior. We studied the red viscacha rat (Tympanoctomys barrerae), a semifossorial rodent with patchy distribution in drylands of west-central Argentina, to provide ecological data on habitat and burrow features of this specialist species. We collected data on 165 burrows and 55 individuals from 2017-2018 and observed correlations between different vegetation types, vegetation diversity, and physical attributes (e.g., soil hardness). A high number of individual red viscacha rats was negatively associated with herbs. The number of burrow entrances was positively associated with harder soils and negatively associated with vegetation cover. Our results suggest that the species' patchy distribution is strongly associated with environmental heterogeneity of these arid environments, and consequently provide an essential step towards conserving their populations across their geographic range. [ABSTRACT FROM AUTHOR]

In highly organized animal societies, behavioural heterogeneity of the members can be crucial for group success. In contrast to eusocial insects, in which task specialization is common, a clear division of labour is often absent in cooperatively breeding species. In these species, contributions to different tasks are sometimes positively correlated across individuals; this phenomenon is called helping syndrome. Previously, eusocial naked mole-rats, Heterocephalus glaber , were thought to display a helping syndrome consisting of burrowing, food carrying and nest building. However, previous studies combined different burrowing tasks in which the locomotive patterns varied widely, possibly missing substantial variation in the behavioural types of individuals. Therefore, it is necessary to reexamine the relations between task contributions among naked mole-rats in more detail. This study analysed six types of activities including four tasks in captive naked mole-rats, and partially confirmed the presence of a helping syndrome in nonbreeding individuals. Frequencies of different activities were significantly positively correlated across individuals in some combinations, but were not significantly correlated in other combinations. Also, individual behavioural types did not simply depend on activity time. Although age- or size-based polyethisms were found in different trends across task types, the results of the correlations between tasks remained mostly unchanged after controlling for the effects of age or body mass. This suggests large interindividual variation that could not be sufficiently explained by age- or size-based polyethisms. The partial support of a helping syndrome suggested that the task allocation system among these eusocial mammals may be more complex than previously assumed. • Contributions to different tasks are often positively correlated in helpers. • The correlations were partially positive in the naked mole-rat. • Age- or size-based polyethisms were found in different trends across task types. • Relationships between tasks did not change even accounting for age or body mass. [ABSTRACT FROM AUTHOR]

In larvae of burrowing mayflies (Ephemeroidea), mandibular tusks are generally associated with burrowing and/or feeding. This study reports, for the first time, the use of mandibular tusks as weapons in the aggressive behavior of the burrowing mayfly Rhoenanthus coreanus (Yoon and Bae, 1985) (Potamanthidae). The larvae used their tusks as weapons in combat behaviors such as tusking, which was observed in 60.81% and 62.98% of the studied males and females, respectively. Most cases involved combat by tusking between females (70.45%), followed by combat between males (21.60%), and combat between male and female individuals (3.97%). Aggressive behavior was more common in female larvae with longer mandibular tusks. Positive relationships were observed between the number of cases of aggressive behavior (i.e., tusking) and the size of mandibular tusks in both male and female larvae (p < 0.001). Female larvae with large mandibular tusks (5.00 ± 0.50 mm) could use their tusks to lift their opponents in a manner similar to horned beetles. Contests typically occurred as a result of territorial conflict and served as a means to find or retain occupied shelters for feeding and hiding. [ABSTRACT FROM AUTHOR]

Globally, grassland degradation is an acute ecological problem. In alpine grassland on the Tibetan Plateau, increased densities of various small mammals in degraded grassland are assumed to intensify the degradation process and these mammals are subject to lethal control. However, whether the negative impact of small mammals is solely a result of population size or also a result of activity and behavior has not been tested. In this study, we use plateau pika as a model to compare population size, core area of colony, and the number of burrow entrances and latrines between lightly and severely degraded grassland. We test whether the alleged contribution of pika to grassland degradation is a result of increased population size or increased burrowing activities of individuals in response to lower food abundance. We found that grassland degradation resulted in lower plant species richness, plant height, and biomass. Furthermore, the overall population size of pika was not significantly affected by location in lightly and severely degraded grassland. However, pika core areas in severely grassland degradation were significantly larger and had significantly higher densities of burrows and latrines. Our study provides convincing evidence that habitat‐induced changes in the behavior of small, burrowing mammals, such as pika, can exacerbate grassland degradation. This finding has significant implications for managing small mammals and restoring degraded grassland ecosystems. [ABSTRACT FROM AUTHOR]

From 2020 to 2023, we used diaries from squirrel hunters to estimate the prevalence of Cuterebra emasculator (Squirrel Bot Fly), which parasitize and burrow under the skin of chipmunks and tree squirrels and form bulges called "warbles", among 3 tree squirrel species in Pennsylvania. We received diaries from 1222 squirrel hunters who harvested 7356 squirrels, of which 249 (3.4%) were reported to have subcutaneous swellings consistent with warbles. Annual prevalence rates varied from 2.5% to 3.9%, were consistently highest during the first week of the hunting season (mid-September), and declined to near zero by December. Overall, warbles were more prevalent in Sciurus carolinensis (Eastern Gray Squirrel; 3.6%) than in S. niger (Eastern Fox Squirrel; 1.3%) and Tamiasciurus hudsonicus (American Red Squirrel; 0.0%). During the first 5 weeks of the squirrel-hunting season, squirrels harvested in southern latitudes had higher warble prevalence rates (6.4%) than in northern latitudes (4.1%), but no associations were observed between prevalence and physiographic province. Providing earlier hunting-season opportunities increased the likelihood that hunters would encounter squirrels with warbles than they did historically. Communications efforts should focus on educating hunters on the occurrence of warbles in squirrels in Pennsylvania, particularly during the early season, and on the lack of public health impacts of this disease on squirrel meat. [ABSTRACT FROM AUTHOR]

Background. The present study investigated the population structure and breeding biology of the burrowing brachyuran crab species Dotilla blanfordi Alcock, 1900, which is commonly found on the sandy beach of Bhavnagar, located on the Gulf of Kachchh, Gujarat coast, India. Methods. Monthly sampling was conducted from February 2021 to January 2022 at the time of low tide using three line transects perpendicular to the water line, intercepted by a quadrate (0.25 m²) each at three different levels of the middle intertidal region: 20 m, 70 m, and 120 m. The quadrate area was excavated up to 30 cm and sieved for specimen collection. The collected specimens were categorised into different sexes viz., male, non-ovigerous female, or ovigerous female. For the fecundity study of D. blanfordi, the carapace width (mm) as a measure of size as well as their wet weight (g), size, number, and mass of their eggs were also recorded. Results. The study revealed sexual dimorphism among the population, with females having significantly smaller sizes as compared to males. The overall population was skewed towards females, with a bimodal distribution of males and females. The occurrence of ovigerous females throughout the year suggests that the population breeds incessantly throughout the year, with the highest occurrence in August and September. A positive correlation was observed between the morphology of crabs (carapace width and wet body weight) and the size, number, and mass of eggs. [ABSTRACT FROM AUTHOR]

Earthworm incubation combined with organic fertilization is promoted as an amended measure to improve soil properties in the ecological restoration of various degraded soils. However, the impacts of earthworms on the soil aggregate size under different organic fertilization in salt‐affected soils have not yet been fully revealed. This hinders our ability to develop policies by which to alleviate soil salinization. In this study, under mesocosm experiments, we investigate the effects of earthworm (Aporrectodea trapezoides) and organic fertilization on the soil aggregate size after 16 weeks of incubation. The soil treated with clover residues showed lower earthworm survival rates and biomass compared to that treated with sheep manure. However, the soil macropores and large macroaggregate were higher in the soils treated with clover residue when earthworms were present. In addition, earthworm burrowing activities form pathways toward food patches improve the characteristics of soil macropores, and the properties of the residue itself play a decisive role. Moreover, whether earthworms are present or not significantly influences the soil macroporosity, macropore number, and soil electrical conductivity. This demonstrates that earthworms exhibit a key feature of soil physical functioning in salt‐affected soil. In conclusion, we propose that the application of earthworms with organic residues in salt‐affected soils is a priority in producing and maintaining favorable soil structure. [ABSTRACT FROM AUTHOR]

Unionoids are in global decline, which may be associated with their complex life cycle. Their juveniles are unique because while hidden (burrowed deeply in bottom sediments) they undergo critical anatomical changes (also developing a characteristic juvenile shell sculpture). Currently, the juveniles' period of life is believed to be both the least known and one of the most vulnerable—thus the possibility of obtaining any biological knowledge is essential for establishing conservation strategies and addressing functional or evolutionary questions. I propose two new methods for visualization of the burrowing behavior of unionoid juveniles within deposits that are cheap and easy: (1) laminated deposits of quartz–aragonite sand for time-stepped X-ray images of bivalve traces, and (2) silica gel serving as 'invisible sand' for direct observations and video recording of behavior within sediments. Both deposits in a pilot study were accepted by the juvenile unionoids—they were stable enough and penetrable, with no observable signs of harmful effects on animals' behavior during trials. In both, juveniles were clearly visible, settled within the top 1 cm layer of deposits. Both methods are promising tools for future in situ within the deposits research on the biology of this much unexplored and vulnerable unionoids' life stage. [ABSTRACT FROM AUTHOR]

Since burrowing crayfish spend most of their lives underground, our knowledge of their biology, behavior, and natural history is limited. Herein, we report life- and naturalhistory observations of Fallicambarus devastator (Texas Prairie Crayfish) from a single en masse collecting event at night where we observed an unusually high degree of surface activity. Based on our observations and the environmental conditions, we hypothesize that the surface activity was triggered by hypoxic conditions within burrows that forced crayfish to the surface, although we do not present burrow oxygen measurements. Throughout the night, we repeatedly observed conspecific interactions between pairs of crayfishes that likely represents territoriality, although we did not observe injurious contests. These interactions were highly stereotypic, which matches reports from other burrowing crayfish observations. Further, the activity we observed was unlikely related to mating, as females were not reproductively active during our observations. Overall, these observations contribute to our understanding of the nature and degree of surface behavior in burrowing crayfishes. We encourage other researchers to attempt similar night-time observations to glean information on unknown aspects of burrowing crayfish behavior, like aggression and mating. [ABSTRACT FROM AUTHOR]

Behavioral adjustments to predation risk not only impose costs on prey species themselves but can also have cascading impacts on whole ecosystems. The greater bilby (Macrotis lagotis) is an important ecosystem engineer, modifying the physical environment through their digging activity, and supporting a diverse range of sympatric species that use its burrows for refuge and food resources. The bilby has experienced a severe decline over the last 200 years, and the species is now restricted to ~20% of its former distribution. Introduced predators, such as the feral cat (Felis catus), have contributed to this decline. We used camera traps to monitor bilby burrows at four sites in Western Australia, where bilbies were exposed to varying levels of cat predation threat. We investigated the impact of feral cats on bilby behavior at burrows, particularly during highly vulnerable periods when they dig and clear away soil or debris from the burrow entrance as they perform burrow maintenance. There was little evidence that bilbies avoided burrows that were visited by a feral cat; however, bilbies reduced the time spent performing burrow maintenance in the days following a cat visit (P = 0.010). We found the risk posed to bilbies varied over time, with twice the cat activity around full moon compared with dark nights. Given bilby burrows are an important resource in Australian ecosystems, predation by feral cats and the indirect impact of cats on bilby behavior may have substantial ecosystem function implications. [ABSTRACT FROM AUTHOR]

Biodiversity loss by grazing pressure has threatened multiple ecosystem functions simultaneously (ecosystem multifunctionality, EMF) in grasslands. Therefore, detecting the relation between EMF and biodiversity under human intervention would provide guidance on the optimization of sustainable grassland management. However, little is known about how grazing effects grassland EMF by mediating biodiversity under different grazing intensities. Here, species and functional diversity were investigated along a longitudinal gradient in Inner Mongolia grassland, and its EMF was quantified comprehensively on six ecosystem functions by an averaging approach, threshold approach and multiple threshold approach to assess the impact of grazing intensity on EMF. There was a significantly lower average EMF index and above‐ground biomass under heavy grazing (HG) than under light grazing (LG). The threshold approach‐based EMF and average EMF index were positively related to species diversity and functional diversity, and species diversity was a stronger driver of EMF than functional diversity. Compared with LG, the slope of the positive relation between EMF and species diversity significantly weakened by 40%–86% under moderate grazing (MG) and decreased by 30%–100% under HG, and reversed to a negative relation between functional diversity and EMF under HG. Additionally, species diversity was more negatively influenced by soil pH and sand content, while functional diversity was more negatively influenced by grazing intensity, indicating that functional diversity was more sensitive to intensive grazing. This study highlights the role of grazing intensity for driving multiple ecosystem functions, and reinforces the significance of managing both species diversity and functional diversity for sustaining productive functional grasslands. [ABSTRACT FROM AUTHOR]

Many studies convincingly documented the diagnostic morphology of Scolicia, establishing a functional link with the burrowing activities of heart urchins, common components of the marine mobile faunas that emerged during the Mesozoic Marine Revolution. However, this ichnotaxon has been repeatedly mentioned in both continental successions and Paleozoic marine strata, even though its diagnostic characteristics were absent. This approach may reflect the implicit belief that behavioural convergence is rampant in the ichnologic record and can be uncritically adopted in almost all cases. We underscore the importance of a definition of Scolicia that is based on diagnostic morphologic features and supported by a solid analysis from the perspective of function and mode of construction. This view of Scolicia highlights its value in paleoenvironmental reconstructions and its significance to unravel macroevolutionary trends. Attribution to an ichnotaxon should involve understanding of morphologic features in terms of its mode of production rather than the mere observation of superficial similarities. [ABSTRACT FROM AUTHOR]

Migration is driven by a combination of environmental and genetic factors, but many questions remain about those drivers. Potential interactions between genetic and environmental variants associated with different migratory phenotypes are rarely the focus of study. We pair low coverage whole genome resequencing with a de novo genome assembly to examine population structure, inbreeding, and the environmental factors associated with genetic differentiation between migratory and resident breeding phenotypes in a species of conservation concern, the western burrowing owl (Athene cunicularia hypugaea). Our analyses reveal a dichotomy in gene flow depending on whether the population is resident or migratory, with the former being genetically structured and the latter exhibiting no signs of structure. Among resident populations, we observed significantly higher genetic differentiation, significant isolation‐by‐distance, and significantly elevated inbreeding. Among migratory breeding groups, on the other hand, we observed lower genetic differentiation, no isolation‐by‐distance, and substantially lower inbreeding. Using genotype–environment association analysis, we find significant evidence for relationships between migratory phenotypes (i.e., migrant versus resident) and environmental variation associated with cold temperatures during the winter and barren, open habitats. In the regions of the genome most differentiated between migrants and residents, we find significant enrichment for genes associated with the metabolism of fats. This may be linked to the increased pressure on migrants to process and store fats more efficiently in preparation for and during migration. Our results provide a significant contribution toward understanding the evolution of migratory behavior and vital insight into ongoing conservation and management efforts for the western burrowing owl. [ABSTRACT FROM AUTHOR]

N. norvegicus supports one of the most commercially-important fisheries in the Mediterranean, and there is considerable interest in developing non-invasive sampling stock assessment methods. Currently, stock assessments are conducted via trawling or by UnderWater TeleVision (UWTV) surveys with limited capacity to provide direct population data due to the burrowing behavior of the species. Here, we used acoustic telemetry to characterize the burrow emergence and movement patterns of N. norvegicus in relation to internal tides and inertial currents in deep-sea habitats of the northwestern Mediterranean. We deployed acoustic tags on 25 adults between May and June 2019, and collected up to 4 months of detection data from each tag. Tagged lobsters spent approximately 12% of their time in door-keeping (i.e., detections at burrow entrance with no displacements) but differences existed among the different behavioral rhythms identified. We observed that mixed day-night, tidal and inertial rhythms in field settings were similar to those observed in laboratory tests. The presence of mixed day-night and tidal periodicity poses the question of why N. norvegicus exhibits flexible responses to environmental cues other than photoperiod. It is possible that tidal regulation of locomotor activity could reduce energy expenditure in relation to hydrodynamic drag. Inertial periodicity occurs in animals with no clear burrowing-oriented activity (always present on the seabed). Possibly, inertial-related movements are the result of a disruption of the biological clock. Our results are discussed in the context of how burrow emergence rhythms may bias UWTV surveys and how novel in situ monitoring approaches address these biases. [ABSTRACT FROM AUTHOR]

Livestock grazing increases the abundance of small burrowing mammals by reducing vegetation height and cover. However, habitats with low food quality may not be able to maintain high-density populations. The combination of an open habitat and high-quality food may be a critical component in understanding the dynamics of small burrowing mammal populations. Plateau pikas are small burrowing lagomorphs endemic to the Qinghai–Tibet Plateau (QTP). Overgrazing by livestock has induced a dramatic increase in the population density of plateau pikas for decades, but the mechanism is poorly understood. On the QTP, degraded meadows caused by livestock overgrazing provide abundant high-protein food resources for plateau pikas, a key factor driving population fluctuations in many small mammals. We examined the effect of protein on the individual fitness of plateau pikas by feeding them three pelleted chows containing 10%, 15% and 20% protein. We hypothesized that high-protein foods would elevate pika fitness by promoting the ability to cope with immediate environmental perturbations and increasing individual growth, immunity, and reproductive performance. We found that individuals from the 10% protein group had a delayed response to acute immobilization stress, while those from the 20% protein group had larger body mass, an increased PHA response, increased anti-KLH IgG levels, and a reduced intensity of coccidian infection. Pikas in the 20% protein group had higher concentrations of gonadotropin-releasing hormone, luteinizing hormone, estradiol, progesterone and testosterone than those in the 10% protein group. These results suggest that the high-protein foods found in heavily grazed meadows may be a key factor in generating and maintaining high-density populations of plateau pikas. [ABSTRACT FROM AUTHOR]

Animal activities threaten levee stability, especially during flood events, increasing levee failure risk. Indeed, while dens alter hydraulically‐induced failure mechanisms, it is difficult to locate them and to know in advance if critical conditions may be reached. This paper demonstrates that it is possible to perform nondestructive surveys to assess the risk of burrow animal activities in levee systems using a ground penetrating radar (GPR) for effective levee structure control, being GPR a nondestructive, expeditious, and cost‐effective geophysical technique. Here, a flood‐prone area in Sicily, where traditional hydraulic phenomena did not justify past levee failure events, is considered a case study. Through a visual inspection survey, several animal holes were recovered. GPR measurements allowed us to explore the levee interior and to detect the presence, distribution, and configuration of dens inside them. It was found that a complex burrow system crosses the entire embankment. Porcupine was recognized as a builder of such cavities. Although, previous studies established the porcupine presence in semi‐humid environments, for the first time, here we provide evidence of the development, articulation, and extension of porcupine burrows inside the levee system. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) symbiosis plays essential roles in shaping rhizosphere soil available phosphorus (P) and organic P mobilization. However, current methods for assessing soil P often do not fully consider the potential role of arbuscular mycorrhizal fungi (AMF) in supplying biologically‐based phosphorus (BBP) to Eucalyptus. This study aims to investigate the effects of AMF on the soil BBP of Eucalyptus plantations and which species prefer to translocate them in phosphorus‐deficient soils. Rhizosphere soil samples of Eucalyptus plantations (in south China) exhibiting different ages (varying between 1 to 12 years) were selected to investigate the evolution of AMF and BBP in soils, as well as their interaction mechanism. The impacts of eight AMF families on BBP were investigated in rhizosphere soil. All BBP contents are significantly positively correlated with Olsen P in the rhizosphere soil of Eucalyptus plantations (p < 0.01). The BBP in soil was notably influenced by AMF diversity, while AMF richness showed little effect on BBP. The abundance of Glomeraceae taxa showed a positive correlation with BBP and a negative correlation with Paraglomeraceae. In contrast, the relative abundance of Glomeraceae was higher in older plantations (including Archaeosporaceae, Claroideoglomeraceae). From the above results, we concluded that different species of the AMF modulated their mycorrhizal traits by improving BBP uptake in the rhizosphere soil. AMF groups (such as Glomeraceae, Archaeosporaceae, Claroideoglomeraceae) should be introduced or amplified at the beginning of planting to promote the uptake and utilization of bioavailable P in Eucalyptus plantations. This study will deepen our understanding of AMF for effective BBP utilization in Eucalyptus plantations. [ABSTRACT FROM AUTHOR]

Norwegian lobster, Nephrops norvegicus, are a generalist scavenger and predator capable of short foraging excursions but can also suspension feed. Existing knowledge about their diet relies on a combination of methods including morphology-based stomach content analysis and stable isotopes, which often lack the resolution to distinguish prey items to species level particularly in species that thoroughly masticate their prey. DNA metabarcoding overcomes many of the challenges associated with traditional methods and it is an attractive approach to study the dietary profiles of animals. Here, we present the diet of the commercially valuable Nephrops norvegicus using DNA metabarcoding of gut contents. Despite difficulties associated with host amplification, our cytochrome oxidase I (COI) molecular assay successfully achieves higher resolution information than traditional approaches. We detected taxa that were likely consumed during different feeding strategies. Dinoflagellata, Chlorophyta and Bacillariophyta accounted for almost 50% of the prey items consumed, and are associated with suspension feeding, while fish with high fisheries discard rates were detected which are linked to active foraging. In addition, we were able to characterise biodiversity patterns by considering Nephrops as natural samplers, as well as detecting parasitic dinoflagellates (e.g., Hematodinium sp.), which are known to influence burrow related behaviour in infected individuals in over 50% of the samples. The metabarcoding data presented here greatly enhances a better understanding of a species' ecological role and could be applied as a routine procedure in future studies for proper consideration in the management and decision-making of fisheries. [ABSTRACT FROM AUTHOR]

The genus Porcellanaster Thomson 1878 has hitherto included two species, the type species P. ceruleus Thomson, 1878 and P. ivanovi Belyaev, 1969. According to WoRMS, the full list of junior synonyms of P. ceruleus consists of 15 specific names, including porcellanasterids of the genera Caulaster Perrier 1882 and Albatrossia Ludwig 1905. In this paper, the morphology of juvenile and adult Porcellanaster and synonymized species from the Atlantic, Pacific, Indian and Southern Oceans are studied. As a result, the composition of the genus Porcellanaster has been revised. The genus Caulaster is re-established and now includes two species, and two new morphological forms of Caulaster are described. The genera Albatrossia and Damnaster H.E.S Clark & McKnight, 1994 are considered junior synonyms of Caulaster. The number of species of the genus Porcellanaster has increased to five, including the recovered P. caulifer, P. fragilis and P. sladeni. The study of representatives of the closely related genus Eremicaster Fisher, 1905 has not led to a change in its species composition. The main diagnostic feature of Caulaster is the presence of adambulacral and dorsal pedicellariae both in adults and juveniles with a major radius (R) greater than 3.5 mm. Pedicellariae have never been found in Porcellanaster or Eremicaster at any stage of postlarval development. The species of Caulaster and some species of Porcellanaster are the smallest porcellanasterids, with the most simplified morphology and reduced papulae and paxillae responsible for respiration. These genera are located on the phylogenetic tree in different clades, which demonstrates the parallel evolution of these taxa and confirms the validity of the genus Caulaster. One of the reasons for miniaturization is likely the burrowing mode of life with feeding on subsurface sediment of low nutritional value. The simplification of morphology can be traced by many morphological charactercs in many ways, including the reduction in papulae and paxillae. [ABSTRACT FROM AUTHOR]

Knowledge of plant species distribution and abundance at different landscape scales and management‐induced degradation is essential for the conservation, planning, and enhancement of the biodiversity of rangelands. In this study, additive partitioning of species diversity based on contribution diversity was used to analyze the interaction of landscape scale and grazing intensity factor to better understand the distribution of rare and common species. A total of 64 units (quadrats) were sampled by using a nested hierarchical sampling design at three scales of two regions (semi‐arid vs. Mediterranean), four sites, and four quadrats in both exclosure and grazing areas. The regional‐scale species richness (γs(q)) was calculated by the sum of the quadrat (αs(q)) and site (βs(q)) scale contributions to the region. The calculated rank of αs(q) indicated that an abundance of rare species for exclosures (α < 0.05) and the Mediterranean area (α < 0.01) was significantly greater than for grazing and the arid area, respectively. The highly palatable plants significantly correlated (α < 0.01) with the contribution diversity components (alpha/beta) in the exclosure areas but not in grazed areas. Furthermore, of the measured explanatory variables, the electrical conductivity (EC) of the soil was significantly negatively related to γs(q) which shows a sensitivity of rare species to the variable environmental conditions that are related to human influences interacting with soil and climatic conditions. The vegetation attributes of biomass and vegetation cover were significantly (α < 0.01) higher for managed exclosure sites than the grazed areas. The findings of this investigation demonstrate an increasing trend for rare species in managed and better environmental conditions. In conclusion, the protection and restoration of plant species diversity in semi‐arid and Mediterranean grasslands in western Iran are possible through the application of sustainable management practices by decision‐makers and managers. [ABSTRACT FROM AUTHOR]

Plastic and microplastic pollution is a complex, muti-faceted challenge that has engaged a broad alliance of stakeholder groups who are concerned with environmental, biotic and human health [[1]]. The toxicity mechanisms triggered by MPs are related to the critical parameters of particles, namely size, concentration, type and form, but they are also dependent on species exposed to MPs and the exposure route. Exposure to MNPs remains subject to much investigation, but the effects of long-term exposure on environmental and human health are not well established [[7]]. Once released, MNPs may sorb many other chemical groups (metals, pharmaceuticals and organic pollutants) and facilitate their transfer to biota [[10], [12]], but knowledge gaps persist regarding the role of MNPs as chemical carriers, particularly when considering the vast array of polymer types, chemicals, environmental transformations, organisms and species-specific physiological parameters that interact with each other [[11]]. [Extracted from the article]

Simple Summary: Octopuses are a diverse group of charismatic animals capable of adapting to a wide range of environments. Marine sediment habitats are the most pervasive environments on Earth and are largely dominated by burrowing organisms. Burrowing, the formation of semi-permanent structures below the surface of the sediment bed, is a novel behavior among octopuses, and the morphology facilitating burrowing in most octopuses is unknown. The goal of this study was to investigate the octopus keel, a fold of skin that protrudes from the lateral margin of the mantle in some species, as a burrowing-associated trait. The keel has been noted in several octopuses known to burrow and has been hypothesized to be associated with burrowing. We found that burrowing octopus species were more likely to also have keels, and that burrowing species of octopus, when held in aquaria, were more likely to lose their keels if they did not burrow. This article represents the first phylogenetic evidence of a connection between keels and burrowing, as well as evidence of the degeneration of keels in non-burrowing Muusoctopus leioderma. The octopus keel is a trait that has been hypothesized to be connected with burrowing in octopuses, but has never been explored in any detail. We investigated the association between these two traits using two approaches. First, we examined the phylogenetic correlation between the presence of a keel and known burrowing behavior in cirrate octopuses. Second, burrowing and non-burrowing captive Muusoctopus leioderma were evaluated for keel prominence to determine whether the keel is lost more rapidly in non-burrowing individuals. Pagel's test for the coevolution of binary characteristics showed the model of best fit for the resulting phylogenetic tree to be one of evolutionary interdependence, and that non-burrowing Muusoctopus leioderma lost their keels over time, while burrowing individuals maintained their keels. Together, these results indicate the keel may be a trait associated with burrowing in octopuses. [ABSTRACT FROM AUTHOR]

Clams from the Corbicula species complex of Asian origin are invasive all over the world, currently extending their distribution to waters of the natural thermal regime in Central European areas. Features linking the clams to their habitats in newly invaded areas have not been fully examined. These include substratum preferences and mobility, which may be key to determining potential niche overlap with native bivalves and gaining a better knowledge of their potential active dispersal and impact. Therefore, our aim was to determine the substratum preferences, horizontal locomotion and burrowing behaviour of three Corbicula morphospecies from Poland, Central Europe: two populations of undetermined Corbicula sp. from an artificially heated habitat and water of the natural thermal regime (cold water), as well as Corbicula leana, and Corbicula fluminea (from artificially heated and cold water, respectively).To determine the preferred substratum range, we used pairwise choice tests with a range of muddy, sandy, and gravelly substrata, as well as zebra mussel shells. Then, we conducted behavioural observations (locomotion and burrowing) by CCTV cameras on substrata found as preferred and non‐preferred by clams.All morphospecies preferred fine‐grained over coarser substrata. C. fluminea from cold water had the widest range of substratum preferences. By contrast, C. leana from artificially heated water and Corbicula sp. from cold water showed the narrowest substratum preferences and spent the longest time deeply burrowed. The longest duration of burrowing activity was noted on non‐preferred coarser substrata, which may indicate difficulties in burrowing. On non‐preferred coarse substrata, C. fluminea (cold water) crawled more than the other morphospecies.Our results show that sediment preferences and behaviour (burrowing and locomotion) differ among various Corbicula morphospecies in Europe, probably also varying their invasive potential.This knowledge is important for determining the overlap of habitat preferences of non‐native Corbicula clams with native bivalves, which is critical for determining potential competition strength, impact, and/or displacement. Our results also indicate that habitats with fine sediments could be more threatened by Corbicula invasions. [ABSTRACT FROM AUTHOR]

Substrate is an important abiotic factor for burrowing shellfish, as it not only provides them with shelter, but also impose significant effect on their physiological metabolism. However, the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions. Consequently, this study investigated the burrowing behavior, feeding physiology and energy budget of Paphia undulata, which is an important aquaculture bivalve species in south China. The clams were exposed to mud and sand substrates with variable physical properties in the laboratory, to determine the suitable substrate conditions for this species. The results showed that the percentage of burrowing clams, digging index, burrowing time, burrowing depth and scope for growth (SFG) were higher in mud substrates with ≥40% water content. Likewise, burrowing percentage, digging index, and burrowing depths were higher in substrates with ≤40% sand content. Moreover, the burrowing depth had significant effect on the feeding physiology and SFG of P. undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths. This study further revealed that low water content in the sediment inhibited physiological performances of P. undulata by impairing feeding or absorption, hence reducing the SFG. In conclusion, mud substrate with ≥40% water content or with ≤40% sand content is suitable for proper burrowing and growth of P. undulata. Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P. undulata. [ABSTRACT FROM AUTHOR]

1-Introduction Carbon dioxide emissions caused by human activities, industrial activities and other sources are increasing day by day. The increase of this gas as an important greenhouse gas can cause fundamental changes in global temperature and climate change. Soil respiration is one of the main natural ways of releasing carbon dioxide into the atmosphere in terrestrial ecosystems, and by studying it, one can gain a lot of knowledge about the global carbon cycle. Tree species can influence soil microbial respiration by affecting biogeochemical processes through the amount of litterfall. On the other hand, the different directions of the trees, due to the changes in the radiation angle, which affects the amount of moisture and temperature, probably cause different responses of soil microbial respiration. 2-Methodology In this research, spatial changes of soil microbial respiration by integrating geographical aspects (north, west, east, south) and five different distances (0.5, 1, 1.5, 2 and 2.5 meters) from the tree trunk for the study of soil microbial respiration in three different oak species (Quercus infectoria Oliv., Quercus brantii Lindl. and Quercus libani Oliv.) were carried out in Baneh, Armardeh forests. Three oak trees were selected in the types with the dominant percentage of the desired species (almost identical in terms of height, diameter at breast and canopy). Soil microbial respiration was recorded using Anderson method and moisture in the laboratory and the temperature of the soil were also recorded at the same time sampling at the sample site (soil samples were taken from a depth of 0-10 cm). One-way analysis of variance and Tukey's test were used to check the significance of the difference in the measured characteristics between different oak species. 3-Results: The results showed that there was no significant difference in the parameters of microbial respiration and moisture between the different aspects of each of the different oak species. The results of soil temperature also showed a significant difference in Quercus brantii species between different aspects, and no significant difference was observed in Quercus infectoria and Quercus libani species. On the other hand, there were significant differences between different distances from the trunk. Also, the results of comparing the average soil microbial respiration between different species were not significant, but the results of comparing the average between different oak species at different distances showed differences between the three species. The main environmental factors in this study included soil temperature and soil moisture, which were significantly affected by spatial heterogeneity. The average soil temperature related to Quercus brantii species had a significant difference in different aspects, which could be due to the difference in the intensity of lighting during the day and the aspects of the sunlight and the change of shade over time. There was a difference in soil temperature at different distances in all three species, and this could be due to the low canopy density of the Zagros forests. 4-Discussion & Conclusions Single trees affect the substrates on which they grow and may leave their traces on the soil through the influence of the canopy and roots. The "single-tree influence" concept envisions the soil landscape as a mosaic of small patches that are spatially and genetically linked to individual trees. There are two aspects to this concept: first, within the circle of influence of each tree, soil properties vary predictably in relation to distance from the trunk and crown edge, and second, at any location relative to the trunk and crown, the degree of feature development varies as well. Soil properties are different among tree species. In other words, the organic matter produced by any tree species is different and the related grass cover contains different proportions of nutrients, lignin and secondary metabolites, which determine the quality of organic matter and the rate of decomposition. This study also showed that the spatial heterogeneity in soil temperature and moisture content may be intrinsic mechanisms that drive differences in soil microbial respiration. These findings can deepen our understanding of changes in microbial respiration and soil respiration and clarify the ecological role of different species for us. [ABSTRACT FROM AUTHOR]

Hg exposure led to significant changes in redox metabolism markers, including increases in malondialdehyde (MDA) content and a general trend of decreasing antioxidant levels. Closer analyses of these results will provide clues to understanding the evolution of antioxidant defense systems, the underlying mechanisms, the subtle connections of the redox metabolism with other vital systems, such as the immune system, and its participation in shaping existent biodiversity. Redox metabolism, encompassing non-radical redox metabolites (e.g., hydrogen peroxide and glutathione), redox-sensitive transcription factors (e.g., Nrf2 and FOXOs), and redox-sensitive proteins (e.g., thioredoxins and peroxiredoxins), forms a network of signaling pathways with extensive effects on various processes in aerobic organisms, spanning from circadian rhythms to the regulation of lifespan. Aerobic organisms have developed a complex system of endogenous antioxidants to manage the reactivity of oxygen and its byproducts. [Extracted from the article]

Comprehending bacterial genomic variation linked to distinct environments can yield novel insights into mechanisms underlying differential adaptation and transmission of microbes across environments. Gaining such insights is particularly crucial for pathogens as it benefits public health surveillance. However, the understanding of bacterial genomic variation is limited by a scarcity of investigations in genomic variation coupled with different ecological contexts. To address this limitation, we focused on Listeria, an important bacterial genus for food safety that includes the human pathogen L. monocytogenes, and analyzed a large-scale genomic dataset collected by us from natural and food-associated environments across the United States. Through comparative genomics analyses on 449 isolates from the soil and 390 isolates from agricultural water and produce processing facilities representing L. monocytogenes, L. seeligeri, L. innocua, and L. welshimeri, we find that the genomic profiles strongly differ by environments within each species. This is supported by the environment-associated subclades and differential presence of plasmids, stress islands, and accessory genes involved in cell envelope biogenesis and carbohydrate transport and metabolism. Core genomes of Listeria species are also strongly associated with environments and can accurately predict isolation sources at the lineage level in L. monocytogenes using machine learning. We find that the large environment-associated genomic variation in Listeria appears to be jointly driven by soil property, climate, land use, and accompanying bacterial species, chiefly representing Actinobacteria and Proteobacteria. Collectively, our data suggest that populations of Listeria species have genetically adapted to different environments, which may limit their transmission from natural to food-associated environments. [ABSTRACT FROM AUTHOR]

Mining is a major threat for tropical rainforests as it induces rapid land degradation. Reforestation of mined areas is important to mitigate degradation and biodiversity losses. Microbial diversity, which serve as a good indicator of environmental perturbations, is crucial for reforestation and ecosystem functioning. Yet, limited information is available on how it is influenced by mining. We investigated the bacterial and fungal taxonomic alpha (richness and abundance) and beta diversities (Bray–Curtis dissimilarities (BCD)), root traits and nutrients among mined, undisturbed, and reforested soils in a tropical rainforest in Hainan Island (China). Soil organic matter (SOM) content was highly associated with bacterial and fungal abundances, fungal species richness, and BCD. Mining‐led vegetation removal largely reduced the SOM, and it decreased bacterial and fungal abundances, fungal species richness, and BCD. After using mined soil to plant multiple fast‐growing tree species, the root traits functioned at the levels of an original secondary forest, and it quickly recovered SOM. This process restored bacterial and fungal abundance, fungal species richness, and BCD to originally undisturbed levels. We further conclude that (i) soil fungal diversity in tropical rainforest is more sensitive to mining and reforestation than bacterial diversity. This could be attributed to largely reduced/increased SOM resulting from loss/gain in vegetation during mining/reforestation, respectively. (ii) Reduced SOM, after mining and removal of vegetation, has profound negative influences on tropical rainforest. (iii) Use of mined soil as a post‐mining substrate along with fast‐growing tree species ensures the recovery of SOM during reforestation, which alleviates the negative impacts of mining on tropical rainforests. [ABSTRACT FROM AUTHOR]

Prioritisation of flood defence maintenance is typically based on visual inspection. However, literature shows that the Probability of Detection (PoD) of visual inspection can vary significantly. Here we investigate the PoD for visual inspections of flood defence structures, the consistency of damage classification, and the influence of different variables on the PoD, such as past experience. Four flood defence sections were inspected by 22 different inspectors for a variety of damage types, such as animal burrowing and damage to block revetments. It is found that the PoD varies significantly both per damage type and inspector. Additionally, the estimated severity of damages varies significantly in comparison to the reference situation: over half of the registered damages is assigned a different severity compared to the reference, which potentially leads to incorrect maintenance measures. A likely explanation for the variation in results is the complexity of inspection guidelines and task definitions. Therefore it is advised to simplify inspection guidelines and use more focussed inspections for the most important types of damage. This likely leads to both a reduction of the number of false negatives associated with an increase in flood risk, and better risk-based asset management and maintenance prioritisation in general. [ABSTRACT FROM AUTHOR]

Animal burrowing activity affects soil texture, bulk density, soil water content, and redistribution of nutrients. All of these parameters in turn influence sediment redistribution, which shapes the earth's surface. Hence it is important to include bioturbation into hillslope sediment transport models. However, the inclusion of burrowing animals into hillslope-wide models has thus far been limited and has largely omitted vertebrate bioturbators, which can be major agents of bioturbation, especially in drier areas. Here, we included vertebrate bioturbator burrows into a semi-empirical Morgan–Morgan–Finney soil erosion model to allow a general approach to the assessment of the impacts of bioturbation on sediment redistribution within four sites along the Chilean climate gradient. For this, we predicted the distribution of burrows by applying machine learning techniques in combination with remotely sensed data in the hillslope catchment. Then, we adjusted the spatial model parameters at predicted burrow locations based on field and laboratory measurements. We validated the model using field sediment fences. We estimated the impact of bioturbator burrows on surface processes. Lastly, we analyzed how the impact of bioturbation on sediment redistribution depends on the burrow structure, climate, topography, and adjacent vegetation. Including bioturbation greatly increased model performance and demonstrates the overall importance of vertebrate bioturbators in enhancing both sediment erosion and accumulation along hillslopes, though this impact is clearly staggered according to climatic conditions. Burrowing vertebrates increased sediment accumulation by 137.8 % ± 16.4 % in the arid zone (3.53 kg ha -1 yr -1 vs. 48.79 kg ha -1 yr -1), sediment erosion by 6.5 % ± 0.7 % in the semi-arid zone (129.16 kg ha -1 yr -1 vs. 122.05 kg ha -1 yr -1), and sediment erosion by 15.6 % ± 0.3 % in the Mediterranean zone (4602.69 kg ha -1 yr -1 vs. 3980.96 kg ha -1 yr -1). Bioturbating animals seem to play only a negligible role in the humid zone. Within all climate zones, bioturbation did not uniformly increase erosion or accumulation within the whole hillslope catchment. This depended on adjusting environmental parameters. Bioturbation increased erosion with increasing slope, sink connectivity, and topography ruggedness and decreasing vegetation cover and soil wetness. Bioturbation increased sediment accumulation with increasing surface roughness, soil wetness, and vegetation cover. [ABSTRACT FROM AUTHOR]

Shrub cover in semiarid rangelands may induce changes in soil resources and ecosystem functioning. However, it is unknown the real influence that shrub vegetation has on soil quality in rangelands used for livestock purposes. We evaluated the shrub cover effect on 12 chemical and biochemical parameters of soil quality. In a semiarid Monte rangeland of Argentina, 6 paddocks were selected and 10 m transects were placed in a patch with (Sh) and without shrubs (WSh). Then, sites with grasses (Sh‐G and WSh‐G), bare ground‐litter (Sh‐BL and WSh‐BL), and under shrub cover (Sh‐S) were selected. In spring 2017 and 2018, a composite soil sample (0–10 cm in depth) was taken at each site (n = 6). Sh‐G and Sh‐S sites presented high values of soil organic matter, soil organic nitrogen, particulate organic matter (POM), and cellulase activity (CA); WSh‐BL and Sh‐BL sites were associated with the lowest contents of these variables. For the rest of the soil quality parameters, the soil sampling sites showed similar values. These results show that woody presence should not be directly linked to soil quality loss. Although we did not detect a shrub effect in all parameters studied, in the context of appropriate grazing management, the presence of plant species of different functional groups has a positive effect on organic matter and N content of soil close to them. Moreover, in these sites, high POM values represent an important reservoir of potentially available nutrients, and promote CA necessary for fresh litter decomposition improving the soil quality of semiarid rangelands. [ABSTRACT FROM AUTHOR]

Information on freshwater mussel behavior in the sediment is scarce worldwide, especially in the Amazon. Laboratory experiments were used to measure the responses of the single mussel species Castalia ambigua in relation to combinations of two co‐occurring different morphotypes (Morphotype I with an elongated shell and Morphotype II with a rounded shell), and three different densities (four, eight, and 16 mussels). Horizontal movements (cm) were calculated by summing changes in the position of each specimen and the shell exposure at the sediment–water interface was obtained by measuring (mm) the exposed part of the shell. Castalia ambigua presented different patterns of shell exposure and horizontal movements linked with shell shape and density. Castalia ambigua Morphotype I remained less exposed with 4 mussels. In contrast, this morphotype was more exposed and tended to aggregate in treatments with 8 and 16 mussels, similar to observations of Morphotype II at all densities. Morphotype II is mainly found in low hydrodynamic energy habitats, suggesting that patches with high densities may stabilize the substrate around the shells of Morphotype I, which is associated with high hydrodynamic energy habitats. We suggest that these patterns may be associated with intrinsic factors of the species, such as reproduction, sexual dimorphism and feeding. Moreover, additional studies using other mussel species belonging to the families Hyriidae and Mycetopodidae are important, since the behavior of these mussels in the sediment may provide useful information on their functional roles in river ecosystems. [ABSTRACT FROM AUTHOR]

Spiders have become a model group for sexual selection and mating system studies, but our understanding of courtship behavior in the group is heavily biased towards the infraorder Araneomorphae ('modern' spiders, such as orb weavers, jumping spiders, wolf spiders, crab spiders and many more). In the Mygalomorphae (tarantulas, trapdoor spiders, funnel‐web spiders and relatives), only a few descriptions of courtship are available and recent developments in the phylogenetics of the group offer an opportunity to remap and investigate the evolution of mating behaviors. Using 81 trials filmed in captivity, we report on the courtship behaviors of the iconic Sydney funnel‐web spider (Atracidae: Atrax robustus), which belongs to a large clade of biologically understudied mygalomorphs. Thirteen distinct behaviors are described for males, out of which at least two seem new to mygalomorphs, while four female behaviors are described. Moreover, the sequences of male behaviors are presented for when they come into contact with females inside or outside of their burrows. The mating positions of the pair, including details of how males use their legs and clasping spurs to grasp the females, are also presented. We discuss our results in a modern phylogenetic context, filling a gap in the understanding of sexual selection in the Mygalomorphae where such studies are rare and biased towards tarantulas. Finally, we attempt to consolidate descriptions of potentially homologous behaviors from several families in the group and offer insights into the evolution of cannibalism, male clasping spurs and female catalepsis (quiescence while mating). [ABSTRACT FROM AUTHOR]