The dung beetle Phelotrupes auratus is a holometabolous insect belonging to the order Coleoptera, and it is widely distributed in Japan. The P. auratus habitat depends on herbivores. P. auratus eats ...the dung of the herbivores and carries it underground for its young. In this process, herbivore droppings disappear from the ground, not only keeping the ground hygienic but also maintaining good soil conditions for plant growth. In this way, a rich ecosystem is maintained. In recent years, the population of P. auratus has decreased, and the main cause has been the decrease in grazing land. It seems that Japanese dung beetles are mainly dependent on herbivores for nutrient sources. However, the physiological relationship between herbivores and P. auratus has not been well investigated. Here, we investigated the nutritional metabolism system of P. auratus by performing whole gene expression analysis of individuals collected from two areas where the ecosystem is occupied by different herbivores. We obtained 54,635 transcripts from P. auratus from Nara Park and Cape Toi and identified 2,592 differentially expressed genes in the fat bodies of the Nara Park and Cape Toi groups. We annotated P. auratus transcripts using Homo sapiens and Drosophila melanogaster genes as references; 50.5% of P. auratus transcripts were assigned to H. sapiens genes, and 54.0% of P. auratus transcripts were assigned to D. melanogaster genes. To perform gene set enrichment analysis, we chose H. sapiens genes for P. auratus transcript annotation. Principal component analysis and gene set enrichment analysis revealed that the nutritional metabolism of P. auratus from Cape Toi might differ from that of P. auratus from Nara Park. We analyzed the nutritional metabolism system of P. auratus from Cape Toi and Nara Park and found that the characteristics of the nutritional metabolism process might depend on the plants consumed by the herbivores. Our findings will contribute to elucidating the relationships among habitat plants, herbivores, and dung decomposers and may aid in the maintenance of sustainable land health cycles.
ABSTRACT
For hundreds of millions of years, large vertebrates (megafauna) have inhabited most of the ecosystems on our planet. During the late Quaternary, notably during the Late Pleistocene and the ...early Holocene, Earth experienced a rapid extinction of large, terrestrial vertebrates. While much attention has been paid to understanding the causes of this massive megafauna extinction, less attention has been given to understanding the impacts of loss of megafauna on other organisms with whom they interacted. In this review, we discuss how the loss of megafauna disrupted and reshaped ecological interactions, and explore the ecological consequences of the ongoing decline of large vertebrates. Numerous late Quaternary extinct species of predators, parasites, commensals and mutualistic partners were associated with megafauna and were probably lost due to their strict dependence upon them (co‐extinctions). Moreover, many extant species have megafauna‐adapted traits that provided evolutionary benefits under past megafauna‐rich conditions, but are now of no or limited use (anachronisms). Morphological evolution and behavioural changes allowed some of these species partially to overcome the absence of megafauna. Although the extinction of megafauna led to a number of co‐extinction events, several species that likely co‐evolved with megafauna established new interactions with humans and their domestic animals. Species that were highly specialized in interactions with megafauna, such as large predators, specialized parasites, and large commensalists (e.g. scavengers, dung beetles), and could not adapt to new hosts or prey were more likely to die out. Partners that were less megafauna dependent persisted because of behavioural plasticity or by shifting their dependency to humans via domestication, facilitation or pathogen spill‐over, or through interactions with domestic megafauna. We argue that the ongoing extinction of the extant megafauna in the Anthropocene will catalyse another wave of co‐extinctions due to the enormous diversity of key ecological interactions and functional roles provided by the megafauna.
In spite of meadow bird protection programs, a severe decline of meadow birds is taking place in the Netherlands. It is hypothesized that pesticides and other agrochemicals may contribute to this ...decline through a negative impact on the entomofauna; a very important food source of meadow birds and especially of their chicks. The present study analysed the presence of 664 pesticides (including biocides and some metabolites) in soil, concentrated feed, manure and some fodder samples from 23 cattle farms in the province of Gelderland (the Netherlands). Furthermore, the presence of 21 anti-parasitic medicines in manure from storage facilities was analysed. For farms practicing field grazing, the number of dung beetles in field samples of fresh manure was determined and a potential relationship with the presence of pesticide residues was explored. Of the 23 farms included in present study, 22 participated in meadow bird protection schemes. A total of 129 different pesticides (including biocides and metabolites) was detected, of which 115 at the 15 conventional farms and 69 at the 8 certified organic farms. The average total amount of pesticide residues detected tended to be lower at organic cattle farms than at conventional farms; for organic concentrated feed this difference was significant at a factor of 3.7. A significant negative correlation was found between the estimated daily intake of insecticides by cattle through the consumption of concentrated feed and hay, and the numbers of dung beetles detected in fresh manure samples in the field. We discuss the most important insecticides detected in concentrated feed and hay, and conclude that their quantities in manure and feed, if compared with LR50 values, give a reason for concern. More research is needed to establish the role of agrochemicals in the decline of meadow birds.
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•129 different pesticides found on 23 cattle farms•69 pesticides found on 8 certified organic cattle farms and 115 at 15 conventional farms•Negative correlation between total insecticide uptake by cows and Coleoptera counts in cow dung•Pesticide concentrations in cattle manure of organic farms 43% lower than of conventional farms•No difference found in the numbers of Coleoptera in manure of organic and conventional farms
Stress-tolerant yeasts are highly desirable for cost-effective bioprocessing. Several strategies have been documented to develop robust yeasts, such as genetic and metabolic engineering, artificial ...selection, and natural selection strategies, among others. However, the significant drawbacks of such techniques have motivated the exploration of naturally occurring stress-tolerant yeasts. We previously explored the biodiversity of non-conventional dung beetle-associated yeasts from extremophilic and pristine environments in Botswana (Nwaefuna AE et.al., Yeast, 2023). Here, we assessed their tolerance to industrially relevant stressors individually, such as elevated concentrations of osmolytes, organic acids, ethanol, and oxidizing agents, as well as elevated temperatures. Our findings suggest that these dung beetle-associated yeasts tolerate various stresses comparable to those of the robust bioethanol yeast strain, Saccharomyces cerevisiae (Ethanol RedTM). Fifty-six percent of the yeast isolates were tolerant of temperatures up to 42 degreesC, 12.4% of them could tolerate ethanol concentrations up to 9% (v/v), 43.2% of them were tolerant to formic acid concentrations up to 20 mM, 22.7% were tolerant to acetic acid concentrations up to 45 mM, 34.0% of them could tolerate hydrogen peroxide up to 7 mM, and 44.3% of the yeasts could tolerate osmotic stress up to 1.5 M. The ability to tolerate multiple stresses is a desirable trait in the selection of novel production strains for diverse biotechnological applications, such as bioethanol production. Our study shows that the exploration of natural diversity in the search for stress-tolerant yeasts is an appealing approach for the development of robust yeasts.
•Eucalyptus edge effects on forest dung beetles can be non-linear and species-specific.•Eucalyptus plantation edge effects penetrated >400m into adjacent Amazonian forests.•Dung beetle responses to ...sand soil content were mostly positive and non-linear.•Forest practitioners should account for exotic tree plantation edge effects on tropical forest-specialist biodiversity.
Large-scale exotic tree planting programmes are widespread in the tropics and growing in the Brazilian Amazon – initially to meet global timber and cellulose demands and now as a nature-based solution to fight climate change and promote global ecosystem restoration. However, we still lack an understanding of how far might edge effects of exotic tree plantations spread into the interior of neighbouring tropical forests. Moreover, few studies have demonstrated how Amazonian forest insect populations may change in response to proximity to exotic tree plantations and along continuous (rather than categorical) gradients of environmental changes. We address these knowledge gaps by investigating how Eucalyptus plantation proximity, litter biomass, soil structure, and canopy openness influence distinct dung beetle responses surveyed within 34 plots of undisturbed primary forest in the Brazilian Amazon. Although the impacts of Eucalyptus plantation proximity were species-specific and varied across behavioural guilds and community metrics, we show that exotic tree plantation edge effects were the main driver of most dung beetle responses, penetrating up to 500–800 m into the forest interior. Dung beetle responses also varied along gradients of soil texture, canopy openness and leaf litter biomass, highlighting the importance of environmental context for dung beetle assemblages and populations. Overall, our findings for dung beetles show that the ongoing expansion of exotic tree plantations may affect our ability to maintain and conserve forest-specialist biodiversity due to edge effects in adjacent tropical forests.
Not only vertebrates but also invertebrates can display personalities and behavioural syndromes. Here, three multiple behaviours (activity, thanatosis and distress call emission) were investigated in ...Copris umbilicatus. Moderate to excellent levels of repeatability were found in all behavioural traits considered. Results suggest the existence of a behavioural syndrome involving thanatosis and activity, with ‘bolder’ individuals exhibiting shorter thanatosis and higher locomotor activity, in contrast with ‘fearful’ individuals which display longer thanatosis and poor locomotor activity. Noticeable differences between individuals, which were not due to differences in sex or body size, could be attributable to differences in personality among individuals. Although personality studies have primarily focused on vertebrates, the evidence showing invertebrates to be capable of displaying personalities has been steadily growing in recent years. In this study, we investigated the behavioural repeatability (repetition of a behaviour over time) and behavioural syndromes (a set of correlated behaviours) in Copris umbilicatus, which is a dung beetle species showing complex sub-social behaviour. We analysed three behaviours (activity, thanatosis and distress call emission) by measuring seven distinct behavioural traits (i.e., three activity-, one thanatosis- and three distress call-related traits). We found moderate to high levels of individual repeatability in all behavioural traits considered. The duration of thanatosis was inversely correlated with two activity traits, hinting a behavioural syndrome for thanatosis and activity, with bolder individuals exhibiting shorter thanatosis and higher locomotor activity in contrast with fearful individuals, which display longer thanatosis and poor locomotor activity. No relationships were found between the behavioural traits and body size or sex. Results of the principal component analysis (PCA) suggested personality differences among individuals. Dung beetles provide an impressive variety of ecosystem services. Since the provision of these services may depend on the personalities represented in local populations and communities, studies on the ecology of personality in dung beetles should be encouraged in future research.
Abstract Land‐use changes and habitat fragmentation can alter biodiversity and associated ecosystem functions. We investigated whether cropland expansion in south‐east Amazonia decreases ecosystem ...functions performed by ants and dung beetles by altering their communities. We sampled both groups in two forest types, in south‐eastern Amazonia: undisturbed riparian forests and riparian forests surrounded by croplands. We sampled ants and dung beetles with epigaeic pitfall traps, and experimentally assessed seed removal and predation by ants, and faeces and seed removal by dung beetles. Although ant and dung beetle abundance and richness did not differ across riparian forests, species composition of both groups did. Ants found seeds faster in undisturbed riparian forests, but the proportion of seed removal did not differ between forests. The abundance of predatory ants and the predation of termites by ants did not differ between forests. Seed and dung removal by dung beetles did not differ across riparian forests. Despite the observed differences in dung beetle composition, we did not find the effects on ecosystem functions probably due a functional redundancy of species. The quality of ecosystem functions provided by ants is lower in riparian forests surrounded by croplands, while changes in dung beetle diversity did not impact their ecosystem functions, with potential effects on the natural recovery of these disturbed riparian forests.
We provide occurrence records of the members of dung beetle's tribe Onitini from the northern parts of Pakistan, including Gilgit-Baltistan, Khyber Pakhtunkhwa Province and Islamabad Capital ...Territory. This study is based on extensive field sampling from different ecological biomes including Alpine Meadows, the Sub-Alpine Zone, Mountain Temperate Forest, and Subtropical Deciduous Forest. As a result, we report six species under two genera of tribe Onitini: Onitis falcatus, O. lama, O. philemon, O. subopacus, O. virens, and Cheironitis arrowi. The genus Cheironitis is recorded for the first time from northern parts of Pakistan. We provide photographs of the dorsal and ventral habitus, diagnosis, distribution maps and identification keys to known genera and species in the tribe Onitini from Pakistan.
We provide occurrence records of the members of dung beetle's tribe Onitini from the northern parts of Pakistan, including Gilgit-Baltistan, Khyber Pakhtunkhwa Province and Islamabad Capital Territory. This study is based on extensive field sampling from different ecological biomes including Alpine Meadows, the Sub-Alpine Zone, Mountain Temperate Forest, and Subtropical Deciduous Forest. As a result, we report six species under two genera of tribe Onitini: Onitis falcatus, O. lama, O. philemon, O. subopacus, O. virens, and Cheironitis arrowi. The genus Cheironitis is recorded for the first time from northern parts of Pakistan. We provide photographs of the dorsal and ventral habitus, diagnosis, distribution maps and identification keys to known genera and species in the tribe Onitini from Pakistan.
A primary goal of community ecologists is to understand the processes underlying the spatiotemporal patterns of species distribution. Understanding the dispersal process is of great interest in ...ecology because it is related to several mechanisms driving community structure. We investigated the mobility of dung beetles using mark-release-recapture technique, and tested the usefulness of the current recommendation for interaction distance between baited pitfall traps in the Brazilian Atlantic Forest. We found differences in mean movement rate between Scarabaeinae species, and between species with different sets of ecological traits. Large-diurnal-tunneler species showed greater mobility than did both large-nocturnal tunneler and roller species. Our results suggest that, based on the analyses of the whole community or the species with the highest number of recaptured individuals, the minimum distance of 50 m between pairs of baited pitfall traps proposed roughly 10 years ago is inadequate. Dung beetle species with different sets of ecological traits may differ in their dispersal ability, so we suggest a new minimum distance of 100 m between pairs of traps to minimize interference between baited pitfall traps for sampling copronecrophagous Scarabaeinae dung beetles.
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•Onthophagus taurus respond plastically to increased temperature mean and variance.•Pupal metabolism was lowest in O. taurus in the warmest, most variable treatment.•Adults were three ...times smaller when reared in the warmest, most variable treatment.•A threshold of mean and variance triggered lower metabolism and smaller body sizes.•Reduced metabolism may not overcome energetic costs of temperature changes.
Though organisms may use thermal plasticity to cope with novel temperature regimes, our understanding of plastic responses is limited. Research on thermal plasticity has traditionally focused on the response of organisms to shifts in mean temperatures. However, increased temperature variation can have a greater impact on organismal performance than mean temperature alone. In addition, thermal plasticity studies are often designed to investigate plasticity in response to more extreme temperatures despite the fact that organisms make physiological adjustments to diurnal temperature fluctuations that they experience. Using pupae of the dung beetle Onthophagus taurus, we investigated the potential for plasticity in response to increasing temperature mean and variance using thermal regimes that were well within the species critical thermal limits. We reared 40 beetles from egg to pupae (n = 20) or adults (n = 20) at one of nine incubation treatments, including all combinations of three mean temperatures (22, 24, 26 °C) and three amplitudes of fluctuation (±2, ±4, ±8 °C). To measure thermal plasticity of pupae, we quantified CO2 production across a range of temperatures (i.e., 15, 20, 25, and 30 °C) for 20 beetles per treatment. The relationship between CO2 production and temperature provides an estimate of energetic costs at a given temperature (i.e., using the intercept) and thermal sensitivity (i.e., using the slope). We reared the remaining O. taurus in each treatment (n = 20) to adulthood and then recorded mass (g) to determine body size, a proxy for fitness. Pupae exhibited thermal plasticity in response to the additive and interactive effects of temperature mean and variance. Pupae reared in the warmest and most variable treatment (26 ± 8 °C) showed the greatest decrease in overall metabolism compared to all other treatments, and adult beetles from this treatment (26 ± 8 °C) were also significantly smaller than adult beetles from any other treatment. We found that both temperature mean and variance contributed to thermal plasticity of pupae and had consequences for adult body size, a trait related to dung beetle fitness. Importantly, the temperatures we used in our treatments are not extreme and are likely well below the critical thermal maxima of the species, demonstrating that organisms can make adjustments to temperatures they experience across diurnal or seasonal timescales.
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