Restore it,and they will come: trap-nesting bee and wasp communities (Hymenoptera: Aculeata) are recovered by restoration of riparian forests

Riparian forests have been greatly affected by anthropogenic actions with formerly continuous riparian forests being slowly converted into small and isolated patches. Riparian forests are extremely important habitats for many groups of insects, including bees and wasps, because they are sources of shelter and food for them and their offspring. There is a growing body of evidence of success in the restoration of riparian forest plant communities; however, little research has been done on the associated invertebrate communities. We test whether restoring plant communities is sufficient for restoring the taxonomic composition of trap-nesting bees and wasps and which functional traits are favored in different sites. We predict that species richness, abundance, and community composition of trap-nesting bees and wasps of riparian sites undergoing restoration will converge on the “target” of a reference site with increasing time, since restoration increases habitat complexity. We also predict that the width of restored patches will also influence the species richness, abundance and community composition of trap-nesting bees and wasps. Bee richness and abundance, and wasp richness, were strongly related to fragment width, but not to age since restoration. Our results indicate that although restored sites are relatively small and scattered in a fragmented landscape, they provide suitable habitat for re-colonization by community assemblages of trap-nesting bees and wasps and the traits selected captured the responses to the habitat restoration. Hence, restored riparian areas can be considered important habitats for invertebrates, thus contributing to an increase in local biodiversity and, possibly, the restoration of some of the ecosystem services they originally provided.     

How to fit the distribution of apex scavengers into land‐abandonment scenarios? The Cinereous vulture in the Mediterranean biome

Aim

Farmland abandonment or “ecological rewilding” shapes species distribution and ecological process ultimately affecting the biodiversity and functionality of ecosystems. Land abandonment predictions based on alternative future socioeconomic scenarios allow foretell the future of biota in Europe. From here, we predict how these forecasts may affect large‐scale distribution of the Cinereous vulture (Aegypius monachus), an apex scavenger closely linked to Mediterranean agro‐grazing systems.

Location

Iberian Peninsula.

Methods

Firstly, we modelled nest‐site and foraging habitat selection in relation to variables quantifying physiography, trophic resources and human disturbance. Secondly, we evaluate to what extent land abandonment may affect the life traits of the species and finally we determined how potential future distribution of the species would vary according to asymmetric socioeconomic land‐abandonment predictions for year 2040.

Results

Cinereous vultures selected breeding areas with steep slopes and low human presence whereas foraging areas are characterized by high abundance of European rabbits (Oryctolagus cuniculus) and wild ungulates. Liberalization of the Common Agricultural Policy (CAP) could potentially transform positively 66% of the current nesting habitat, favouring the recovery of mature forest. Contrarily, land abandonment would negatively affect the 63% of the current foraging habitat reducing the availability of preferred food resources (wild European rabbit). On the other hand, the maintenance of the CAP would determine lower frequencies (24%–22%) of nesting and foraging habitat change.

Main conclusions

Land abandonment may result into opposite effects on the focal species because of the increase in nesting habitats and wild ungulates populations and, on the other hand, lower availability of open areas with poorer densities of European rabbits. Land‐abandonment models’ scenarios are still coarse‐grained; the apparition of new human uses in natural areas may take place at small‐sized and medium‐sized scales, ultimately adding complexity to the prediction on the future of biota and ecosystems.

     

Matching consumer feeding behaviours and resource traits: a fourth‐corner problem in food‐web theory

For decades, food web theory has proposed phenomenological models for the underlying structure of ecological networks. Generally, these models rely on latent niche variables that match the feeding behaviour of consumers with their resource traits. In this paper, we used a comprehensive database to evaluate different hypotheses on the best dependency structure of trait‐matching patterns between consumers and resource traits. We found that consumer feeding behaviours had complex interactions with resource traits; however, few dimensions (i.e. latent variables) could reproduce the trait‐matching patterns. We discuss our findings in the light of three food web models designed to reproduce the multidimensionality of food web data; additionally, we discuss how using species traits clarify food webs beyond species pairwise interactions and enable studies to infer ecological generality at larger scales, despite potential taxonomic differences, variations in ecological conditions and differences in species abundance between communities.     

Gut Microbes Egested during Bites of Infected Sand Flies Augment Severity of Leishmaniasis via Inflammasome-Derived IL-1β

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Expected impacts of climate change threaten the anuran diversity in the Brazilian hotspots

We performed Ecological Niche Models (ENMs) to generate climatically suitable areas for anurans in the Brazilian hotspots, the Atlantic Forest (AF), and Cerrado (CER), considering the baseline and future climate change scenarios, to evaluate the differences in the alpha and beta diversity metrics across time. We surveyed anuran occurrence records and generated ENMs for 350 and 155 species in the AF and CER. The final predictive maps for the baseline, 2050, and 2070 climate scenarios, based on an ensemble approach, were used to estimate the alpha (local species richness) and beta diversity metrics (local contribution to beta diversity index and its decomposition into replacement and nestedness components) in each ~50 × 50 km grid cell of the hotspots. Climate change is not expected to drastically change the distribution of the anuran richness gradients, but to negatively impact their whole extensions (i.e., cause species losses throughout the hotspots), except the northeastern CER that is expected to gain in species richness. Areas having high beta diversity are expected to decrease in northeastern CER, whereas an increase is expected in southeastern/southwestern CER under climate change. High beta diversity areas are expected to remain in the same AF locations as the prediction of the baseline climate, but the predominance of species loss under climate change is expected to increase the nestedness component in the hotspot. These results suggest that the lack of similar climatically suitable areas for most species will be the main challenge that species will face in the future. Finally, the application of the present framework to a wide range of taxa is an important step for the conservation of threatened biomes.     

Experimental field tests of Batesian mimicry in the swallowtail butterfly Papilio polytes

The swallowtail butterfly Papilio polytes is known for its striking resemblance in wing pattern to the toxic butterfly Pachliopta aristolochiae and is a focal system for the study of mimicry evolution. Papilio polytes females are polymorphic in wing pattern, with mimetic and nonmimetic forms, while males are monomorphic and nonmimetic. Past work invokes selection for mimicry as the driving force behind wing pattern evolution in P. polytes. However, the mimetic relationship between P. polytes and P. aristolochiae is not well understood. In order to test the mimicry hypothesis, we constructed paper replicas of mimetic and nonmimetic P. polytes and P. aristolochiae, placed them in their natural habitat, and measured bird predation on replicas. In initial trials with stationary replicas and plasticine bodies, overall predation was low and we found no differences in predation between replica types. In later trials with replicas mounted on springs and with live mealworms standing in for the butterfly's body, we found less predation on mimetic P. polytes replicas compared to nonmimetic P. polytes replicas, consistent with the predator avoidance benefits of mimicry. While our results are mixed, they generally lend support to the mimicry hypothesis as well as the idea that behavioral differences between the sexes contributed to the evolution of sexually dimorphic mimicry.     

Yeast communities of the cactusPilosocereus arrabidae and associated insects in the Sandy Coastal Plains of Southeastern Brazil

The yeast communities from necrotic tissues, decaying flowers and fruits, and from larval feeding sites of the mothSigelgaita sp. in the cactusPilosocereus arrabidae were surveyed in three restinga ecosystems in Southeastern Brazil. Insects associated with these substrates were sampled to verify the vectoring of yeasts. The cactusPilosocereus arrabidae was shown to have four different yeast communities associated with it. Necrotic stems had a diverse yeast community with the prevalent speciesPichia barkeri, Candida sonorensis, Pichia cactophila, Geotrichum sp.,Myxozyma mucilagina andSporopachydermia sp. A, representing about 80% of the total isolates.Pichia sp. A and aCandida domercqii-like species represented more than 90% of the yeast isolates from decaying flowers. Fruits had a heterogeneous yeast community with typical fruit yeasts of the genusKloeckera, basidiomicetous anamorphs of the genusCryptococcus, the black yeastAureobasidium pullulans, Pichia sp. A, aCandida domercqii-like species, and some cactophilic yeasts, especiallyClavispora opuntiae. The feeding site ofSigelgaita sp. larvae hadClavispora opuntiae as the prevalent species. Insect vectors are suggested as one the most important factors influencing the composition of these yeast communities.