Phenotypic differentiation in a resilient dung beetle species induced by forest conversion into cattle pastures

The Impact of Eucalyptus and Pine Plantations on the Taxonomic and Functional Diversity of Dung Beetles (Coleoptera: Scarabaeidae) in the Southern Region of Ecuador

This study sheds light on the complex relationship between land use, biodiversity, and the functional traits of dung beetles in Ecuador. The results indicate that the richness and abundance of dung beetles vary across different land uses and regions, with forests generally having a positive impact, while eucalyptus and pine plantations have a negative effect in certain areas. Specific indicator species, such as Homocopris buckleyi for forest areas and Onthophagus curvicornis for eucalyptus plantations, were identified. This study also found that functional diversity analysis, based on morphological traits, revealed that certain traits, such as biomass, pronotum width, head width, and elytra length, were significant contributors to differences in dung beetle communities across various land uses and regions. This study highlights the potential conservation value of certain modified habitats and emphasizes the importance of considering both taxonomic and functional diversity when assessing the impact of land use on the ecosystem services provided by dung beetles. It underscores the potential value of plantations as refuges for dung beetle communities and the need for long-term assessments to better understand biodiversity changes over time.

Livestock grazing impact differently on the functional diversity of dung beetles depending on the regional context in subtropical forests

The replacement of native forest by cattle pastures reduces functional diversity; however, little is known about whether the changes depend on regional variation. Dung beetles are one of the most diverse and functionally important taxa; through organic matter burial, dung beetles improve soil quality. We collected dung beetles in native forests and cattle ranching areas in subtropical forests with contrasting climatic conditions: the Atlantic Forest, the Humid Chaco, and the Dry Chaco. We measured 11 traits related to the ecology and the physiology of species. Irrespectively of the region, functional richness was higher in forests (native and with cattle) when compared to open pastures. Humid forests (Atlantic Forest and Humid Chaco) showed higher functional richness than Dry Chaco. Functional dispersion in humid forests was similar between native forest and livestock systems, however, functional dispersion in the Dry Chaco was higher in open pastures compared to native forest. According to our results, native forests and forests with cattle maintain functional diversity in all regions. However, in the case of open pastures, the response depends on the regional context; the replacement of native forest by open pastures strongly affected functional diversity in humid forests and showed less impact on dry forest.

Morphological responses of three persistent native anuran species after forest conversion into monoculture pine plantations: tolerance or prosperity?

Species loss by habitat replacement operating as an ecological filter is a well-known consequence of modern human activities. In contrast, the ecological and evolutionary response of species overcoming those filters in converted habitats has not been thoroughly explored. Species that persist are subject to novel and potentially stressful conditions that may induce certain morphological changes. We evaluated changes in the functional morphology of three anuran species persisting after the conversion of areas of the Atlantic Forest into pine plantations. We specifically evaluated differences in body size and body condition indices, head width, and hind legs' length between adult individuals from both habitats and sexes. Habitat conversion and sexual dimorphism affected the morphology of the three anurans, with varying effects upon species and traits. Regarding the effect of habitat conversion, Elachistocleis bicolor increased body condition in plantations with no changes in the other traits, Physalaemus cuvieri showed only a marginal increment in residual body mass in plantations, and Odontophrynus americanus exhibited a substantial increment in body size while maintaining its body condition in plantations. Remarkably, none of the results suggested these persistent anurans were stressed by forest conversion. This study shows that habitat conversion may induce intraspecific morphological changes in ecologically relevant traits of persistent species, and that disturbed areas do not necessarily imply stressful, low quality habitats affecting all persistent native species negatively.