Reproductive conflicts within animal societies occur when all females can potentially reproduce. In social insects, these conflicts are regulated largely by behaviour and chemical signalling. There is evidence that presence of signals, which provide direct information about the quality of the reproductive females would increase the fitness of all parties. In this study, we present an association between visual and chemical signals in the paper wasp Polistes satan. Our results showed that in nest-founding phase colonies, variation of visual signals is linked to relative fertility, while chemical signals are related to dominance status. In addition, experiments revealed that higher hierarchical positions were occupied by subordinates with distinct proportions of cuticular hydrocarbons and distinct visual marks. Therefore, these wasps present cues that convey reliable information of their reproductive status.

In the Epiponini, queen number may vary from many to few during the colonial cycle. This cyclical oligogyny may be important for the maintenance of high genetic relatedness found in several taxa of epiponines. Even though queen reduction in accord with the colony cycle has either been demonstrated or inferred for many taxa, the factors responsible for queen number reduction remain largely unknown. In this study, behavioral interactions (queen-queen and queen-worker) were analyzed in Asteloeca ujhelyii. Conflicts among queens leading to queen elimination were more intense during colony establishment, and queens' behavioral performances were significantly correlated with their potential reproductive capacity. Frequency of workers' testing behaviors toward queens did not relate as a function of the colony cycle. Thus, it seems that in Asteloeca ujhelyii cyclical oligogyny is indeed behaviorally mediated.

Padrões de Forrageamento na Vespa Noturna Apoica flavissima van der Vecht (Hymenoptera: Vespidae) RESUMO -O comportamento de forragear é fundamental para o desenvolvimento das colônias de insetos sociais, pois permite que as colônias sejam supridas de alimento, água e materiais utilizados para a construção dos ninhos. Vespas sociais do gênero Apoica Lepeletier (Hymenoptera: Vespidae) têm comportamento de forrageamento noturno como uma de suas principais características, porém estudos sobre aspectos abióticos que influenciam esse comportamento são ainda escassos. Este estudo mostra que a freqüência de forrageamento foi maior em noites de luas cheia e crescente. Além disso, as saídas e retornos ao ninho correlacionaram-se positivamente com o período da noite e a temperatura. Os resultados sugerem que a luminosidade é um componente importante nas atividades gerais das colônias do gênero. PALAVRAS-CHAVE: Insecta, Polistinae, inseto social, Epiponini, bionomia ABSTRACT -Foraging behaviour has a remarkable significance to colonies of social insects since it is directly related to the supply of food, water, and pulp. Social wasps of the genus Apoica Lepeletier are primarily nocturnal, but studies concerning the general aspects related to this habit are still scarce. This study showed that the rates of foraging flights were higher during the full moon and last quarter moon phases. Frequencies of arrival and departure were correlated with time and temperature at night. The results suggest that the moonlight is an important component to general activities in this genus.

The capacity to distinguish colony members from strangers is a key component in social life. In social insects, this extends to the brood and involves discrimination of queen eggs. Chemical substances communicate colony affiliation for both adults and brood; thus, in theory, all colony members should be able to recognize fellow nestmates. In this study, we investigate the ability of Dinoponera quadriceps workers to discriminate nestmate and non-nestmate eggs based on cuticular hydrocarbon composition. We analyzed whether cuticular hydrocarbons present on the eggs provide cues of discrimination. The results show that egg recognition in D. quadriceps is related to both age and the functional role of workers. Brood care workers were able to distinguish nestmate from non-nestmate eggs, while callow and forager workers were unable to do so.