The Effects of Nectar-Robbing on Fruit Production in Sparattosperma leucanthum (Bignoniaceae)

Many animals behave as robbers or thieves of floral resources, causing damage to floral tissues or consuming resources used to attract pollinators, or producing effects similar to emasculation by reducing the pollen load in the anthers (which generally results in losses in terms of sexual reproduction). The present work examined the direct and indirect impacts caused by nectar-robbing on the reproductive success of Sparattosperma leucanthum. Different manipulations of the flowers were tested to determine if fruit production was influenced by the perforations made in the floral tissues (direct damage), and if there were changes in visitation frequencies or in the behaviors of effective pollinators (indirect damage). Perforations made by nectar robbers did not lower the reproductive success of the plant species studied. The bee Trigona spinipes was the most frequent visitor and caused the largest perforations in the calyx and corolla of S. leucanthum. Additionally, we noted the occurrence of pollen theft by this same bee in flowers that had been protected against nectar-robbing. These results suggest that if S. leucanthum had developed a mechanism of resistance to robbery by T spinipes it would probably have experienced even lower pollination levels as a result of reductions in the quantities of pollen available for transfer by effective pollinators. We were not able to evaluate if nectar depletion through robbery modified the behavior of the effective pollinators (bumblebees of the genus Bombus).

Do fato à notícia e ao filme: o assalto ao trem pagador

Pós-graduação em Comunicação - FAAC

Uma abordagem para um plano de gestão de fluxo de dados na TV Unesp

Pós-graduação em Televisão Digital: Informação e Conhecimento - FAAC

Modelos organizadores na resolução de conflitos morais: um estudo com adolescentes autores de infração

Pós-graduação em Psicologia - FCLAS

Dinâmica populacional e comportamento predatório individual da aranha social Parawixia bistriata (Rengger) (Araneae: Araneidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Adolescentes em conflito com a lei e suas famílias

Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

Um modelo para a criminalidade no município de São Paulo em 2001

This work aims to estimate an empirical model for three kinds of crime in Sao Paulo city: homicides, robberies and car thefts. It uses as geographical units the areas belonging to each police districts and takes in account spatial effects among the variables. The results show important differences when we deal with crime against people and crime against property.