Browsing by Author "Vera, Gabriel A. Brito"

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    Atypical case of sex ratio disruption in Tabanidae collections with Malaise traps in Ecuadorian forests
    (2024) Buestan, Jaime; Vera, Gabriel A. Brito
    Male horseflies have low capture rates in Malaise traps, a widely documented pattern observed in numerous ecological studies. We present findings from a specific locality in Ecuador where a departure from this established pattern is observed. In this locality, males accounted for 59.14% of Tabanidae captures. The disruption in capture patterns observed using Malaise traps represents an uncommon feature in the scientific literature and during collections conducted over eight years in Ecuador. Despite the inherent limitations of Malaise traps in capturing male horseflies, it is possible that under specific conditions, such as the presence of optimal aggregation areas for horseflies, Malaise traps may enhance the capture efficiency of males. Additionally, we provide a detailed discussion on the disruption and disparity in capture sex proportions in Tabanidae, commonly reported in the scientific literature.
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    Nitrogen overfertilization: Impact on ecological interactions and floral morphology in a peri-urban environment
    (2024) Vera, Gabriel A. Brito; Calderon, Ximena; Perez, Fernanda
    Nitrogen is a crucial element that affects plant metabolic processes and indirectly influences the structure and dynamics of ecological interactions in terrestrial ecosystems. Since the invention of the Haber-Bosch process, human activity has significantly influenced the amount of nitrogen released into the environment. However, how do these overfertilization processes affect flora and fauna in urban ecosystems? In our experiments, we used elevated nitrogen concentrations to simulate terrestrial eutrophication processes in Nicotiana tabacum L. We evaluated reproductive traits such as floral morphology using geometric morphometrics. Additionally, nectar volume and solute concentration, along with other vegetative traits, were quantified. Subsequently, the impacts of these modifications on herbivory and pollination interactions in a peri-urban environment were measured. Overfertilization resulted in notable modifications to the floral shape of the lobes, as well as a significant increase in percentage of herbivory by chewing insects, without affecting floral visitation rates. We also observed that elevated herbivory on fertilised plants did not show a direct correlation with overall pollination rates per plant or seed set. In contrast, the reduction in leaf size during the second phase of the experiment, owing to overfertilization effects, affected seed production. The roles of potential pollinators and their influence on seed quantity in control plants are discussed. Nitrogen is a crucial element not only for plants in natural terrestrial ecosystems but also plays a fundamental role in the modification and shaping of reproductive and vegetative structures. Moreover, it affects the functionality of ecological interactions of pollination and herbivory in anthropogenic environments, such as peri-urban areas.
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    Richness, Endemism and Seasonality of Horseflies (Diptera: Tabanidae) in Forests of the Equatorial Pacific Region of Ecuador
    (2024) Buestan, Jaime; Pazmino-Palomino, Alex; Vera, Gabriel A. Brito
    The Equatorial Pacific Region (EPR) in Ecuador is characterized by high rates of vegetation diversity, and rapid loss of vegetation cover due to anthropogenic pressures. In this study, general ecological aspects of the Tabanidae family, including richness, endemism, and seasonality, were evaluated. Analyses reveal that approximately 42% of the species recorded for Ecuador are present in the EPR, and out of the 84 species cataloged in the EPR, 6 are endemic, representing an endemism of 7.14%. Furthermore, it was established that tabanid populations in a coastal dry forest significantly increased their population density during the dry season, while decreasing during the wet season.
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    Use of artificial nest boxes by two species of small, arboreal mammals in Ecuadorian tropical dry forest
    (2022) Vera, Gabriel A. Brito; Salas, Jaime A.; Heimpel, George E.; Bulgarella, Mariana
    We record, for the first time, the nest structure of two species of small, non-volant mammals, Marmosa simonsi and Rhipidomys latinamus, inside artificial nest boxes in a dry forest ecosystem of Western Ecuador. We describe the nests and categorized them as rearing nest, permanent resting nest and transient refuge, depending on their intended use. Artificial nest boxes provide an optimal place for pup rearing and resting for small mammals, and they can be useful for ecological studies of elusive, poorly-known mammalian species.