Biology subjects

Marcolin, L.

Publications and source records attributed to Marcolin, L..

3 recordsLinked to original sources

bioRxiv2026

West Nile virus response to mosquito and avian biodiversity in rural environments

ContextThe relationship between biodiversity and zoonotic disease risk is a central topic in community ecology, yet empirical evidence in Europe remains scarce and often contradictory compared to North American studies. Addressing this gap is fundamental to better anticipate zoonotic disease dynamics. ObjectivesWe investigated the transmission dynamics of West Nile virus (WNV) in Veneto (Italy), a major European hotspot. Because this vector-borne pathogen is primarily transmitted by Culex mosquitoes and maintained by several avian hosts, we analysed how multiple facets of both avian and mosquito biodiversity influence its transmission. MethodsUsing Generalized Additive Models (GAMs) trained on longitudinal entomological and ornithological surveillance data, we modelled the probability of WNV presence in mosquito pools as a function of host and vector community structure. To isolate the effects of biodiversity, we explicitly controlled for climatic and landscape covariates. ResultsIn agricultural landscapes, we found that higher avian diversity leads to higher viral presence, driven by the dominance of highly competent synanthropic hosts. Conversely, a dilution effect emerges across the broader regional landscape where areas of higher ecological integrity allow for more complex and functionally diverse avian communities. Furthermore, we identified significant vector-mediated regulation, where high abundances of mammophilic vectors effectively suppress viral prevalence through larval competition. ConclusionsOur findings suggest that the dilution effect is a property of intact ecosystems which can be lost, or even locally reversed, in anthropogenically altered environments. Because such habitat degradation fundamentally alters zoonotic transmission dynamics, landscape planning must prioritize ecological restoration. Ultimately, embedding these practices into One Health strategies represents a proactive approach to mitigating disease emergence.

ecology↗

bioRxiv2025

Two forms, two functions: functional strategies of parasitoid bristle flies and their larvae

Species with complete metamorphosis undergo substantial changes in ecological functions, especially parasitoid insects with parasitic larvae and free-living adults. While parasitoids play essential ecosystem roles, limited knowledge is available about their shifting functional strategies. Here we focus on parasitoid bristle flies (Diptera: Tachinidae) to investigate the relationship between larval vs adult functional strategies. We retrieved trait data for 767 European species and defined functional trait spaces for larvae and adults. We then measured both functional distinctiveness (rarity in functional trait combination) and specialisation (variety of resources consumed). We found little correspondence in the functional distinctiveness of adults and larvae, with highly distinct larvae generating either functionally distinct or functionally common adults. In contrast, only specialised larvae (attacking a limited number of hosts) give origin to specialised adults (feeding on a limited number of flowers). This suggests selective pressure towards specialisation might act synergistically across life stages, if trophic resources are restricted in space for both the larva (e.g. caterpillar host) and adult (e.g. flowers). Global change can generate complex patterns of functional homogenisation in parasitoids, which can occur at different (or both) life stages and lead to ecosystem-wide consequences: from the outbreak of herbivore insects to the loss of pollination capacity.

ecology↗

bioRxiv2025

Mapping the habitat suitability of Culex pipiens in Europe using ensemble bioclimatic modelling

Anthropogenic pressure on natural ecosystems has profoundly influenced the dynamics of disease vectors, altering their distribution and phenology, and increased the risk of vector-borne diseases. Culex pipiens is a widespread mosquito species and an important vector of zoonotic pathogens in Europe, including West Nile virus. Understanding Cx. pipiens distribution is essential to orient monitoring and mitigation strategies for vector-borne disease risk. Here, we employed an ensemble modelling framework to investigate the climatic and environmental determinants of Cx. pipiens distribution in continental Europe. We integrated high-resolution occurrence data from entomological surveillance with bioclimatic, topographic, and anthropogenic variables. Our findings identified imperviousness as the most influential predictor of Cx. pipiens distribution, with a strong association with human-modified low-elevation areas that reflects its adaptability to anthropogenic environments. The ensemble prediction approach we employed demonstrated higher predictive accuracy and transferability compared to individual models during independent block validation. These results emphasize the need to incorporate anthropogenic factors into disease vector distribution models to support evidence-based surveillance and control strategies, while also offering updated, robust, and spatially explicit predictions of the habitat suitability for Cx. pipiens in Europe. Overall, this study highlights the role of human modification of the natural environment in shaping Cx. pipiens distribution, extending previous knowledge on the role of urban areas.

ecology↗