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The Pantanal is the largest wetland in the world and a World Heritage Site. During 2019–2020, the Pantanal has experienced the most severe burning in its history, with vast destroyed areas of vegetation and killed wildlife. Since the long‐term damage caused by fire to the Pantanal is still unknown, understanding how the biodiversity responds to post‐fire disturbance over a short‐term is an important step for conservation initiatives.The authors studied the effects of fire on dung beetle communities, a recognised bioindicator group, in the Brazilian Pantanal. For this, the authors assessed the patterns of taxonomic and functional diversity between unburned and burned sites (16 months post‐fire).The authors found that taxonomic and functional diversity of dung beetles were similar between unburned and burned grasslands, but with a distinct taxonomic composition post‐fire. The functional traits composition was similar between unburned and burned sites, demonstrating that this metric is less sensitive to fire effects in the Brazilian Pantanal.The study's results provide evidence that dung beetles exhibit high resistance to the occurrence of fire and fast recovery from its consequences. Thus, due to its ecological functions (secondary seed dispersion, nutrient cycling and others), these insects may assist ecological restoration of burned sites, being useful tools in restoration approaches for areas of the Pantanal that have been affected by fire.Finally, combining traditional taxonomic community attributes with functional diversity measurements provides a more comprehensive picture of responses of dung beetle communities, post‐fire, over a short‐term in the Brazilian Pantanal. [ABSTRACT FROM AUTHOR]

The dung roller beetle Canthon smaragdulus (Scarabaeinae) has a pair of pygidial glands whose secretions have different functions. However, the factors influencing the production of pygidial secretions in these dung beetles are not known. This study is the first to evaluate differences in the amount of pygidial secretions produced by C. smaragdulus individuals in relation to body mass, sex and social status (mature males and females alone or in couple). We also evaluated whether the production of pygidial secretions is stable over time in individual beetles. To achieve this, we collected pygidial secretions from 120 C. smaragdulus individuals and measured their body mass and body size. Secretions were collected twice more, for a total of three samples per specimen, which were obtained every seven days. Our results suggest that alone males produce higher amounts of pygidial secretions than females alone, couple males and couple females. Only the body mass of couple males was positively correlated with the amount of pygidial secretions. This was probably due to couple males remaining in the nest for a few days. Our results confirm that the production of pygidial secretions in dung roller beetles can be influenced by body mass, sex and social status. Thus, further experiments should assess the production of pygidial secretions throughout the dung beetle life cycle under different behavioural contexts such as defence, protection of the nest and reproduction. [ABSTRACT FROM AUTHOR]

There is increasing recognition that community assembly theory can offer valuable insights for ecological restoration. We studied community assembly processes following tropical forest restoration efforts, using dung beetles (Scarabaeinae) as a focal taxon to investigate taxonomic and functional patterns of biodiversity recovery. We evaluated the relative importance of the local environment (i.e., canopy cover, understory cover, tree basal area, and soil texture), landscape context (i.e., habitat patch proximity and availability and percentage of surrounding area classified as natural forest or Eucalyptus spp. plantation), and space (i.e., spatial proximity of the study areas to estimate dispersal limitation or unmeasured spatially structured processes) on dung beetle species and functional trait composition across a gradient of 15 restoration sites in Brazilian Atlantic Forest. We also assessed which factors were the primary determinants in the establishment of individual dung beetle functional groups, classified according to size, food relocation habit, diet, and period of flight activity. Both species and functional trait composition were most strongly influenced by the local environment, indicating that assembly was predominantly driven by niche-based processes. Most of the variation explained by space was co-explained by local environment and landscape context, ruling out a strong influence of dispersal limitation and random colonization on assembly following restoration. In addition, nearly all of the variance explained by landscape context was co-explained by local environment, suggesting that arrival and establishment at a site depends on both local and landscape-scale environmental factors. Despite strong evidence for niche-based assembly, a large amount of variation remained unexplained in all models, suggesting that stochastic processes and/or unmeasured environmental variables also play an important role. The relative importance of local environment, landscape context, and space changed considerably when analyzing the assembly mechanisms of each functional group separately. Therefore, to recover distinct functional traits in restoration sites, it may be necessary to manipulate different components of the local environment and surrounding landscape. Overall, this study shows that assembly rules can help to better understand recovery processes, enabling improvement of future restoration efforts. [ABSTRACT FROM AUTHOR]

Patterns of diversity and community composition in forests are controlled by a combination of environmental factors, historical events, and stochastic or neutral mechanisms. Each of these processes has been linked to forest community assembly, but their combined contributions to alpha and beta-diversity in forests has not been well explored. Here we use variance partitioning to analyze ~40?000 individual trees of 49 species, collected within 137 ha of sampling area spread across a 900-ha temperate deciduous forest reserve in Pennsylvania to ask (1) To what extent is site-to-site variation in species richness and community composition of a temperate forest explained by measured environmental gradients and by spatial descriptors (used here to estimate dispersal-assembly or unmeasured, spatially structured processes)? (2) How does the incorporation of land-use history information increase the importance attributed to deterministic community assembly? and (3) How do the distributions and abundances of individual species within the community correlate with these factors? Environmental variables (i.e., topography, soils, and distance to stream), spatial descriptors (i.e., spatial eigenvectors derived from Cartesian coordinates), and land-use history variables (i.e., land-use type and intensity, forest age, and distance to road), explained about half of the variation in both species richness and community composition. Spatial descriptors explained the most variation, followed by measured environmental variables and then by land-use history. Individual species revealed variable responses to each of these sets of predictor variables. Several species were associated with stream habitats, and others were strictly delimited across opposing north- and south-facing slopes. Several species were also associated with areas that experienced recent (i.e., <100 years) human land-use impacts. These results indicate that deterministic factors, including environmental and land-use history variables, are important drivers of community response. The large amount of "unexplained" variation seen here (about 50%) is commonly observed in other such studies attempting to explain distribution and abundance patterns of plant communities. Determining whether such large fractions of unaccounted for variation are caused by a lack of sufficient data, or are an indication of stochastic features of forest communities globally, will remain an important challenge for ecologists in the future. [ABSTRACT FROM AUTHOR]