7 research outputs found
Wood-boring beetles promote ant nest cavities: extended effects of a twig-girdler ecosystem engineer
No full textAnt Fauna on Cecropia pachystachya Trécul (Urticaceae) Trees in an Atlantic Forest Area, Southeastern Brazil
No full textCecropia are pioneer successional trees frequently associated with ants. Generally a single dominant colony of Azteca ant inhabits each mature Cecropia tree, but other ant species may be found living or foraging on the same tree. In this study, we assessed the diversity of ant species on Cecropia pachystachya trees in two sites in the Brazilian Atlantic Forest: a dust-free roadside and a dusty roadside. We also investigated the influence of tree architecture on ant species richness. We found a total of 24 ant species distributed in 11 genera and five subfamilies on C. pachystachya trees; 18 in the dust-free roadside and 14 in the dusty roadside. We found up to five ant species on a single tree, but only Azteca alfari was frequently encountered. Ant species richness per tree did not differ significantly between sites and was related to tree architectural traits. On the other hand, ant species composition on trees differed significantly between sites. Our study indicates that heavy dust deposition on Cecropia trees may affect associated ant communities, not by changing ant species richness, but by causing different species to live and forage on trees under different dust exposure
Ant Fauna on Cecropia pachystachya Trécul (Urticaceae) Trees in an Atlantic Forest Area, Southeastern Brazil
No full textCecropia are pioneer successional trees frequently associated with ants. Generally a single dominant colony of Azteca ant inhabits each mature Cecropia tree, but other ant species may be found living or foraging on the same tree. In this study, we assessed the diversity of ant species on Cecropia pachystachya trees in two sites in the Brazilian Atlantic Forest: a dust-free roadside and a dusty roadside. We also investigated the influence of tree architecture on ant species richness. We found a total of 24 ant species distributed in 11 genera and five subfamilies on C. pachystachya trees; 18 in the dust-free roadside and 14 in the dusty roadside. We found up to five ant species on a single tree, but only Azteca alfari was frequently encountered. Ant species richness per tree did not differ significantly between sites and was related to tree architectural traits. On the other hand, ant species composition on trees differed significantly between sites. Our study indicates that heavy dust deposition on Cecropia trees may affect associated ant communities, not by changing ant species richness, but by causing different species to live and forage on trees under different dust exposure
Explaining export regional involvement through marketing strategy : the case of Spanish companies exporting to Latin America
No full textThe equivalence between the absence of arbitrage and the existence of an equivalent martingale measure fails when an infinite number of trading dates is considered. By enlarging the set of states of nature and the probability measure through a projective system of topological spaces and Radon measures, we characterize the absence of arbitrage when the time set is countable
Arthropod diversity in a tropical forest
No full textMost eukaryotic organisms are arthropods. Yet, their diversity in rich terrestrial ecosystems is still unknown. Here we produce tangible estimates of the total species richness of arthropods in a tropical rainforest. Using a comprehensive range of structured protocols, we sampled the phylogenetic breadth of arthropod taxa from the soil to the forest canopy in the San Lorenzo forest, Panama. We collected 6144 arthropod species from 0.48 hectare and extrapolated total species richness to larger areas on the basis of competing models. The whole 6000-hectare forest reserve most likely sustains 25,000 arthropod species. Notably, just 1 hectare of rainforest yields >60% of the arthropod biodiversity held in the wider landscape. Models based on plant diversity fitted the accumulated species richness of both herbivore and nonherbivore taxa exceptionally well. This lends credence to global estimates of arthropod biodiversity developed from plant models.SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe
