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Ant Queens (ant + queen)
Selected AbstractsMating triggers dynamic immune regulations in wood ant queensJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2009G. CASTELLA Abstract Mating can affect female immunity in multiple ways. On the one hand, the immune system may be activated by pathogens transmitted during mating, sperm and seminal proteins, or wounds inflicted by males. On the other hand, immune defences may also be down-regulated to reallocate resources to reproduction. Ants are interesting models to study post-mating immune regulation because queens mate early in life, store sperm for many years, and use it until their death many years later, while males typically die after mating. This long-term commitment between queens and their mates limits the opportunity for sexual conflict but raises the new constraint of long-term sperm survival. In this study, we examine experimentally the effect of mating on immunity in wood ant queens. Specifically, we compared the phenoloxidase and antibacterial activities of mated and virgin Formica paralugubris queens. Queens had reduced levels of active phenoloxidase after mating, but elevated antibacterial activity 7 days after mating. These results indicate that the process of mating, dealation and ovary activation triggers dynamic patterns of immune regulation in ant queens that probably reflect functional responses to mating and pathogen exposure that are independent of sexual conflict. [source] Recognition of Host Plant Volatiles by Pheidole minutula Mayr (Myrmicinae), an Amazonian Ant-Plant SpecialistBIOTROPICA, Issue 5 2009Wesley F. C. Dáttilo ABSTRACT In the tropics, several ant species are obligate inhabitants of leaf pouches and other specialized structures in plants known as myrmecophytes. However, the cues used by ant queens to locate suitable host-plants following dispersal remain poorly understood. Here we tested the hypothesis that Pheidole minutula queens use volatiles to distinguish their host Maieta guianensis (Melastomataceae) from other sympatric myrmecophytes. To do so, we used a Y-tube olfactometer to quantify the preference for volatiles of different plant species. Our results indicate that P. minutula queens discriminate the chemical volatiles produced by its host-plant from those of other sympatric ant-plant species. However, queens failed to distinguish the volatiles of Maieta from those of the ant-plant Tococa bullifera (Melastomataceae), with which P. minutula is not mutualistically associated. Nevertheless, a strong preference for Maieta over Tococa was observed during a subsequent bioassay, where the ants had physical contact with a domatium of each plant species. These results suggest that additional, short distance mechanisms are also necessary for host discrimination. Overall, our findings suggest that the high degree of compartmentalization observed in symbiotic ant,plant relationships is achieved, at least in part, by the relatively high degree of specificity in host selection displayed by foundress queens. [source] |