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A mechanistic understanding of the relationship between multiple dimensions of species diversity and ecosystem functioning is needed to safeguard ecological processes critical to human well‐being.We evaluated how taxonomic, functional and phylogenetic diversities, as well as the assembly mechanisms of dung beetle communities, percent forest cover and landscape fragmentation, affect dung burial, soil excavation efficiency and dung fly larvae abundance in Los Tuxtlas Biosphere Reserve, a complex tropical landscape. Dung beetle functions were measured in 15 landscapes representing a gradient of forest cover loss (0%–100%).Phylogenetically clustered assemblages of large tunneler dung beetles showed the highest dung burial efficiency across the landscape. Fly larvae abundance was negatively correlated with the taxonomic diversity and functional evenness of dung beetles. Forest cover and landscape fragmentation did not significantly affect dung burial effectiveness, suggesting a high degree of functional redundancy.Dung burial efficacy is mainly driven by selection mechanisms, in which a single or a few phylogenetically close species disproportionately affect a given function. Fly larvae abundance was controlled by a complementary functional effect where each dung beetle species additively affected fly larvae survival. Hence, multiple functions are maintained by contrasting mechanisms and different diversity dimensions. High dung beetle species richness may foster pest fly control in tropical landscapes such as Los Tuxtlas Biosphere Reserve.Our findings highlight the need to assess multiple dimensions of diversity since each can operate concurrently and contrastingly on the different ecological functions of species assemblages. [ABSTRACT FROM AUTHOR]

Gut bacteria help dung beetles metabolize nutrients contained and synthesize those unavailable in their food, depending on the ecological scenario in which they develop. However, less is known about the influence of environmental and behavioral factors on the taxonomic composition of bacterial gut communities in Scarabaeinae beetles. To address this research topic, we analyzed 13 tropical dung beetle species in the Los Tuxtlas Biosphere Reserve, Mexico, to understand how the beetle tribe, habitat, food preference, food relocation, and parental care influence the composition of gut bacterial communities. We found that the beetle tribe is the primary factor impacting the taxonomic composition of gut bacterial communities. Among them, Deltochilini displayed the highest variability in diversity due to the different combinations of habitat and food preferences among its species. On the other hand, the other tribes studied did not exhibit such variable combinations. Habitat emerged as the second most influential factor, with forest-dwelling beetles displaying higher diversity. This can be attributed to the heterogeneous environments within tropical forests, which offer a greater diversity of food resources. In contrast, grassland beetles, living in more homogeneous environments and relying on cow feces as their main food source, exhibited lower diversity. Our findings suggest a correlation between bacterial diversity and food resource availability in complex habitats, such as tropical forests, which offer a wider array of food sources compared to simpler environments like grasslands. [ABSTRACT FROM AUTHOR]

Copyright of Entomologia Experimentalis et Applicata is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Applied Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We analysed the genetic divergence and morphology of the aedeagus (i.e. phallobase and parameres) in Canthon cyanellus at different geographical levels. The results from both approaches were compared with the current taxonomic assignment of the C. cyanellus complex, which includes three subspecies. We found a high variation in all the morphological characters of the aedeagus in the populations analysed; the morphometric variation was not geographically structured, either by population or by region. The genealogical analysis indicates a significant genetic structure that does not match either the morphological variation in the male genitalia or the previous subspecific taxonomic classification. Our results suggest that the morphological variation of the aedeagus is seemingly not an isolating reproductive barrier and that the intra- and interpopulation morphological variability of the aedeagus in the C. cyanellus complex does not permit the division into several species. We suggest that other evolutionary forces, such as genetic drift and sexual selection, have influenced the evolution of the male genitalia and the incipient differentiation of this species complex. [ABSTRACT FROM AUTHOR]

Background. Anthropized landscapes play a crucial role in biodiversity conservation, as they encompass about 90% of the remaining tropical forest. Effective conservation strategies require a deep understanding of how anthropic disturbances determine diversity patterns across these landscapes. Here, we evaluated how attributes and assembly mechanisms of dung beetle communities vary across the Selva El Ocote Biosphere Reserve (REBISO) landscape. Methods. Community attributes (species diversity, abundance, and biomass) were assessed at the landscape scale, using spatial windows and vegetation classes. Windows were categorized as intact, variegated, or fragmented based on their percent cover of tropical forest. The vegetation classes analyzed were tropical forest, second-growth forest, and pastures. Results. We collected 15,457 individuals and 55 species. Variegated windows, tropical forests, and second-growth forests showed the highest diversity values, while the lowest values were found in intact windows and pastures. Landscape fragmentation was positively and strongly related to dung beetle diversity and negatively related to their abundance; biomass was positively associated with forest cover. Beta diversity was the primary driver of the high dung beetle diversity in the landscape analyzed. Discussion. The landscape heterogeneity and its biodiversity-friendly matrix facilitate the complementarity of dung beetle assemblages in the Selva El Ocote Biosphere Reserve. Random processes govern beta diversity patterns in intact and variegated windows. Therefore, vegetation cover in the region is sufficient to maintain a continuous flow of dung beetles between forested landscape segments. However, intense anthropic disturbances acted as deterministic environmental filters in fragmented windows and pastures sites, leading to biotic homogenization processes. Our results suggest that increasing habitat variegation in highly fragmented sites is an effective strategy to prevent or buffer homogenization processes in the REBISO landscape. [ABSTRACT FROM AUTHOR]

Male dung beetles compete to obtain food and females, and early resource recognition and appropriation increase the probability of mating. The outcome of such encounters is expected to be defined by self‐ and the opponent's health condition. In this study, we analyzed the effect of body condition and immune defense on the contest dynamics between males that rolled a food ball with a partner female (owner males) and intruder males of dung beetle Canthon cyanellus. Body condition was measured as body size, body dry mass, lipid mass, and muscle mass; immune defense was estimated via phenoloxidase activity. Owner males with higher lipid mass contacted the food ball significantly earlier than owner males with lower lipid mass. Individuals with lower phenoloxidase activity started to roll food balls earlier than individuals with higher phenoloxidase activity. Owner males that had higher body dry mass, compared to female partners, began to roll the food ball significantly earlier than male–female pairs with lower differences in dry mass. Heavier males won significantly more contests than lighter males. Our results suggest that the health condition is a key factor related to the dynamics and outcome of male–male contests for resources and females in C. cyanellus. Consequently, differences in individual condition are main determinants of contest outcomes in dung beetles. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fights among females are frequent, although less attention has been placed on them than on male fights. They arise when females compete for food, oviposition, mates, brooding sites, or access to resources which increase offspring survival. It has been shown that the outcome of female fights may be less predictable by asymmetries in resource holding power, than in male fights. Male roller beetles fight over food resources, food balls, needed for mating and nesting, and it has been show in some species that asymmetries in reproductive experience and resource holding power in terms of size predict fight outcome, including ties in which contenders cut and split the food ball. In this study, we tested the influence of asymmetries in reproductive status (experience) and body size on female fight outcome in the carrion roller beetle Canthon cyanellus cyanellus. As predicted, and as previously found for males of the same species, female reproductive status of both contenders and relative size predict fight outcome. Larger and reproductively experienced contenders have a higher probability of winning. Furthermore, ties are more likely in fights involving opposing asymmetries (vgr. Large reproductively naïve owner versus small reproductively experienced intruder). Also as predicted, food ball splitting is more likely to be started by the predicted loser. This mode of resource sharing may be the result of a fighting strategy in which the costs of continuing to fight are greater than the benefits of not splitting, if a fraction of the disputed resource is more than the minimum needed for the present reproductive needs, and reduces costs associated to a longer fight. [ABSTRACT FROM AUTHOR]

The article focuses on a research conducted in order to evaluate the influence of body size and shape on the strength of inter-specific competitive interactions within a community of Neotropical dung beetles from the Atlantic Forest in Serra do Japi, Brazil. It discusses the use of the geometric morphometrics and the principal components analysis in understanding the influence of size and body shape on the strength of inter-specific competitive interactions.

Many studies have analyzed the effect of forest fragmentation on dung beetle diversity in tropical landscapes. Few of them, however, have analyzed how forest fragmentation affects the assemblage structure of necrophagous beetles and their removal rates of carrion in tropical forests. This study compares the effect of the time of the day in which carrion is offered to dung beetles (in the morning or at night) on the rates of carrion removal over time (12, 24, and 36 h) in tropical rain forest fragments of different sizes. Fragment size, time, and carrion offer had no effect on carrion removal rates in this study, but these factors affected abundance and species richness of necrophagous beetles. Carrion removal was the highest 12 h after the carrion had been offered. The average rate per hour of carrion removal in all fragments after 12 h was 4.47 g/h, after 24 h was 3.27 g/h, and 36 h later 2.64 g/h. Carrion removal rates are likely to be affected by beetle abundance and species richness. The most abundant species captured when carrion was offered at night was Coprophanaeus telamon Harold, a nocturnal necrophagous tunneler beetle. When carrion was offered in the morning, the most abundant species was the diurnal copro-necrophagous roller beetle Canthon cyanellus LeConte. Large nocturnal tunneler beetles were only found in large fragments, but small diurnal roller species were abundant in both large and small fragments. Our results suggest that different species contribute unevenly in different ways to carrion removal in tropical forest fragments. Carrion removal is not affected by fragment size per se, but by the fragmentation process. [ABSTRACT FROM AUTHOR]

Many studies have evaluated the effect of forest fragmentation on dung beetle assemblage structure. However, few have analyzed how forest fragmentation affects the processes carried out by these insects in tropical forests where their food sources consist mainly of dung produced by native herbivore mammals. With the conversion of forests to pastures, cattle dung has become an exotic alternative and abundant food for dung beetles. This study compares dung removal rates of native (monkey) and exotic (cow) dung in different-sized fragments of tropical rain forests, during the dry and rainy seasons at the Los Tuxtias Biosphere Reserve. Dung removal rates were affected by season, dung type, and the interaction between resource type and season. During the dry season, the removal rates of monkey dung were somewhat similar than during the rainy season, whereas the removal rates of cow dung were much higher during the rainy season. Dung beetle biomass and species richness were almost three times greater in monkey dung than in cow dung. Monkey dung attracted species belonging to the dweller, roller, and tunneler guilds; cow dung attracted mostly tunnelers. Therefore, the use of exotic dung may result in a biased misconception of the rates of dung removal in tropical forest and an underestimation of dung beetle diversity. This study highlights the importance of working with natural tropical forest resources when attempting to identify realistic tendencies concerning processes in natural habitats and those modified by fragmentation and by other human activities. [ABSTRACT FROM AUTHOR]

• Increased forest coverage preserves the taxonomic diversity of dung beetles. • Forest fragmentation lowers dung beetles' functional evenness and divergence. • Dung beetle assemblages show greater taxonomic than functional differences. • Dung beetles are functionally resilient to forest cover loss and fragmentation. • Forest coverage favors the coexistence of small-sized dung beetle species. We evaluated how the taxonomic and functional diversity of dung beetles responds to landscape fragmentation in Los Tuxtlas Biosphere Reserve (LTBR). We sampled dung beetle assemblages in 15 landscapes (spatial windows) representing a gradient of forest cover loss and evaluated the degree of forest fragmentation in each landscape. The percentage of forest coverage of each landscape had a significant positive effect on species richness (0 D), Shannon diversity (1 D), and functional divergence of dung beetles. Forest fragmentation was negatively related to Simpson diversity (2 D) , biomass, and functional evenness of dung beetles, whereas their functional richness expanded as forest fragmentation increased. Taxonomic and functional beta diversity were positively correlated; the former was driven mainly by species replacement and the latter by nestedness. Functional alpha and beta diversities varied mostly at random, as did the probability of co-occurrence between species. However, the few non-random positive associations between species involved small-bodied forest dung beetles. Species and their ecological traits are lost randomly in the landscape, suggesting a surprising resilience of dung beetle assemblages to forest cover loss. Nevertheless, loss and fragmentation of forest coverage had an unbalancing effect on dung beetle abundance and trait distribution, reducing their functional evenness, and divergence while favoring the establishment of small-sized species. In conclusion, although the LTBR has buffered further loss of dung beetle species and functional richness, it cannot effectively safeguard all aspects of their functional diversity. Our results suggest that the recovery of the original forest cover and large mammals is crucial for maintaining the taxonomic and functional diversity of dung beetles in tropical rainforests. [ABSTRACT FROM AUTHOR]

• The creation of the Reserve allowed the recovery of beetle assemblages through time. • Species turnover is the main component that drives beta diversity in the Reserve. • Forest indicator species increased 17 years after the creation of the Reserve. Studies addressing the temporal changes of ecological communities within fragmented forests transformed into natural protected areas are urgently needed. The creation of the Los Tuxtlas Biosphere Reserve (LTBR) in 1998 stopped the deforestation process of the northernmost tropical rainforest of the Neotropical region, allowing the analysis of the long-term effects on native communities after the halting of habitat fragmentation. We compared the diversity of dung beetles in 11 forest fragments and eight pastures in the LTBR between two periods: 1999–2000, the early years after the creation of the LTBR; and 2016–2017, i.e., 17 years later. Species richness and abundance of dung beetles were similar in both periods, being higher in forest fragments than in pastures; however, the dominant species were different in each period in both forest fragments and pastures. The number of habitat indicator species increased in 2016–2017 compared to 1999–2000, with a high species diversity of forest indicators relative to pasture indicators at both periods. Alpha and gamma diversities were lower in 1999–2000 than in 2016–2017. Beta-diversity at the spatial level was strongly driven by species turnover, which was higher in pastures than in forest fragments. All functional groups (dwellers, rollers, and tunnellers) showed higher abundances in forest fragments than in pastures in both 1999–2000 and 2016–2017 periods. Our results suggest that stopping the fragmentation process in the LTBR has allowed the survival of native dung beetle assemblages, which are undergoing a recovery process of their populations and ecological functions over the years. [ABSTRACT FROM AUTHOR]

In recent years much has been learned about the intrasexual relationships and nesting behavior of Scarabaeus Linnaeus and Kheper Janseen. In this study, based on the published literature, as well as our unpublished observations, the intra- and intersexual relationships during periods of feeding, copulation and nesting are analyzed in detail for both genera. We define two types of behavior: 1) One that we refer to as the sacer type, the most characteristic traits of which are the male offering the female a prenuptial ball of dung which she consumes but does not use for nesting; later when the ovary is mature the female can nest alone without copulating again and without the support of the male. 2) That which occurs in several African species of Scarabaeus and Kheper where the female copulates with different males, but once the ovary is developed nesting is a joint activity carried out by the male and female; the female making one or several brood balls from the rolled and buried dung ball and all of the brood balls receiving postoviposition care. Although almost all nesting females store sperm from previous copulations in their spermathecae, the presence of the last male mate during nesting appears to be associated with an increase in his paternity as he is the last male to have copulated with the female and prevents the intrusion of other males. [ABSTRACT FROM AUTHOR]

• Urbanization threatens biodiversity and ecosystem services. • Coprophagous and roller dung beetles were severely affected by urbanization. • Urban forests serve as reservoirs of dung beetles. • Urbanization drives the homogenization and impoverishment of dung beetle assemblages. The maintenance of forest fragments within urban landscapes is essential for human well-being, as the loss of biodiversity may result in a reduction of ecological services in cities. Conserving diverse functional groups within urban landscapes is essential, since it is directly related with the resilience of such ecosystems. Through the use of indicator groups, it is possible to draw predictions on how communities respond to increasing urbanization. The goal of our study was to assess how the increase of urban land cover affects the assemblage and functional groups of dung beetles (Scarabaeinae) that inhabit forest fragments in a tropical city. We sampled dung beetles in nine fragments embedded in the metropolitan region of João Pessoa, Brazil. Increasing urbanization negatively affected the abundance of coprophagous species, as well as the species richness, abundance and biomass of roller beetles. Assemblages from the most urbanized forest fragments were significantly different from the other fragments. According to the decomposition of β diversity, species turnover was the main process shaping the dung beetle assemblages in João Pessoa. In this study we provide evidence that specific functional groups of dung beetles are affected by urbanization. Furthermore, as each functional group has different strategies to occupy habitats and use resources, urbanization has contrasting effects for each group. Our results confirm that dung beetles are highly sensitive to urbanization and that protected areas within cities are fundamental to conserve biodiversity and ecosystem services. [ABSTRACT FROM AUTHOR]

The assessment of species' diet and trophic plasticity serve as key elements to understand their adaptations to harsh ecosystems, such as deserts and dry forests. Among dung beetles, coprophagy is the main feeding habit, which may be substituted or complemented by other unusual diets, such as granivory and necrophagy. This study presents new records of dung beetle uncommon diets in Caatinga, the largest Seasonally Dry Tropical Forest in America. We include novel descriptions of the genera Dichotomius Hope, 1838 and Canthidium Erichson, 1847 in using and removing seeds in Caatinga. We also present the first report of dung beetles from Caatinga attracted to dead millipedes, specifically for Coprophanaeus pertyi (Olsufieff, 1924). Also, we found goat hairballs along with the roller beetle Deltochilum verruciferum Felsche, 1911 inside a pitfall trap, suggesting that this species may use animal fur to feed or breed. Finally, we included an updated list on unusual food records of dung beetle species in Caatinga dry forest. Our findings indicate that dung beetles in Caatinga display diverse feeding habits in response to extreme environmental conditions and/or limited resources. We expand the still-scarce knowledge regarding dung beetle feeding ecology outside their interaction with dung or the soft tissues of carrion. Despite our findings, new evidence is essential to reinforce our understanding on trophic plasticity of dung beetles in Caatinga. A better comprehension of resource plasticity by dung beetles will also be a significant input for biodiversity conservation due to the changes in food availability in anthropogenic landscapes. • Resource scarcity in arid environments may favor unusual diets in dung beetles. • Fur, seeds, and millipedes are consumed by dung beetles in Caatinga dry forest. • Unusual dung beetles' diet in Caatinga dry forest suggests resource-use plasticity. [ABSTRACT FROM AUTHOR]

The expanded use of macrocyclic lactones (ML) to treat endo- and ectoparasites in cattle in tropical regions, can reduce dung beetle populations, and thus interrupt the dung removal process in cattle pasture ecosystems. During the reproductive period (the rainy season) of two functional groups of dung beetles (paracoprid and telocoprid Scarabaeinae), we compared dung removal amount in ranches where ML are and are not used in Yucatan, Mexico, through exclusion traps baited with 500 g of ML-free cow dung. On each ranch, two transects (separated by 500 m) with six traps each, were set up for 24 hours. After this time, all the dung remnants in each trap were obtained and weighed in order to record the dung removal. Results showed that dung removal amounts were similar in ranches with and without ML use. Dung beetles removed 40.1% of all cow dung weighed. Paracoprids removed 87.46% and telocoprids 12.54% of all the dung that was removed. Our results indicated that the ecological function of dung beetles in the pastures studied, does not seem to be affected by the ML use, and that paracoprid species removed most of the dung. For both types of ranch, further studies that take into account the population dynamics and movement of the most important dung beetle species in the region are required, coupled with laboratory studies evaluating the effect of ML on their reproductive success. This could give some light on the effect of ML on the ecological function of this important insect group in the sustainability of cattle production systems. Rev. Biol. Trop. 64 (3): 945-954. Epub 2016 September 01. [ABSTRACT FROM AUTHOR]

• Important ecosystem services depend on the health and behavior of individual animals. • Parasitism and malnutrition affected dung burial carried out by dung beetles. • Three dung beetle species responded differently, suggesting physiological diversity. • Dung burial was driven by terminal investment in reproduction and compensatory feeding. • Energetic depletion is a risk of maintaining high levels of dung burial. Ecosystem services relies on several insects that provide fundamental functions. Despite the quality of these ecosystem services depends on insect diversity, abundance and biomass, little is known about the effects that individual body condition has over such services. One prediction is that starving or sick animals may provide a reduced service. Dung beetles bury dung in forests and cattle farms, contributing to soil fertilization and reduction of greenhouse gas emissions from livestock. However, some species are highly sensitive to habitat disturbance and this leads to important losses of ecosystem services in disturbed areas. Here we experimentally tested the effect of diet quality and parasite pressure impact on dung removal rate using three species of dung beetles from contrasting habitats. We exposed wild beetles to an immune challenge combined with experimental diets that varied in protein content. We predicted that dung removal would be better carried out by healthy and well-fed individuals. However, if a species incurs in compensatory feeding or terminal investment in reproduction, ill individuals will still exhibit intense dung removal and reproductive activity but with a physiological cost. For Euoniticellus intermedius beetles, the immune challenge reduced dung removal rates, and this was because the challenge reduced the weight, although not the number of built brood masses. This suggests that implanted individuals made an intense reproductive effort. Therefore, a strategy of terminal investment in reproduction might be occurring. In the same species, couples fed low-protein diets increased dung removal rates compared to control-fed animals, probably as a compensatory feeding strategy that increased energetic condition. Conversely, Onthophagus incensus and O. rhinolophus beetles did not change dung removal rates despite suffering changes in energetic condition resulting from treatment. This is the first evidence that ecosystem services provided by dung beetles depend on individual health and nutritional status that drive reproductive and feeding behavior. Understanding the environmental factors that affect individual physiology and behavior is fundamental to guarantee conditions not only for the survival of key species but also for the maintenance of ecosystem services. [ABSTRACT FROM AUTHOR]