We used a standard sampling protocol to measure elevational patterns of species richness and abundance of eusocial paper wasps (Hymenoptera: Vespidae) in Costa Rica. The sample transect of six sites spanned approximately 2000 m in elevation from lowland to montane forest. Species accumulation curves and species richness estimates both document a low elevation peak in paper wasp species richness...

Fig trees are pollinated by fig wasps, which also oviposit in female flowers. The wasp larvae gall and eat developing seeds. Although fig trees benefit from allowing wasps to oviposit, because the wasp offspring disperse pollen, figs must prevent wasps from ovipositing in all flowers, or seed production would cease, and the mutualism would go extinct. In Ficus racemosa, we find that syconia ('f...

Empirical observations have shown that cooperative partners can compete for common resources, but what factors determine whether partners cooperate or compete remain unclear. Using the reciprocal fig-fig wasp mutualism, we show that nonlinear amplification of interference competition between fig wasps-which limits the fig wasps' ability to use a common resource (i.e. female flowers)-keeps the c...

Figs and fig wasps form a peculiar closed community in which the Ficus tree provides a compact syconium (inflorescence) habitat for the lives of a complex assemblage of Chalcidoid insects. These diverse fig wasp species have intimate ecological relationships within the closed world of the fig syconia. Previous surveys of Wolbachia, maternally inherited endosymbiotic bacteria that infect vast nu...

Theory predicts that mutualisms should be vulnerable to invasion by cheaters, yet mutualistic interactions are both ancient and diverse. What prevents one partner from reaping the benefits of the interaction without paying the costs? Using field experiments and observations, we examined factors affecting mutualism stability in six fig tree-fig wasp species pairs. We experimentally compared the ...

Specialized face learning, the ability to learn and remember faces better than other visual stimuli, occurs across a wide range of social animal taxa. However, the ontogeny of specialized face learning, specifically whether it develops due to innate, learned, or a combination of innate and learned factors, remains debated in the literature. Empirical data on face specialization has supported al...

Mohammed Reza Zargaran, Nadir Erbilgin, and Youbert Ghosta (2012) Changes in oak gall wasps species diversity (Hymenoptera: Cynipidae) in relation to the presence of oak powdery mildew (Erysiphe alphitoides). Zoological Studies 51(2): 175-184. Plant-mediated interactions usually lead to multipartite interactions in a community of organisms. To evaluate the impact of oak powdery mildew Erysiphe ...