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| Author(s): |
Jéferson Pedrosa dos Santos
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Ribeirão Preto. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (PCARP/BC) |
| Defense date: | 2021-08-02 |
| Examining board members: |
Fabio Santos do Nascimento;
Denise de Araujo Alves;
Cristiano Menezes
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| Advisor: | Fabio Santos do Nascimento |
| Abstract | |
The perception of inner and outdoor environments in relation to colonies and their interactive responses were fundamental for the ecological success of social insects. As a consequence, several aspects of their social behavior are mediated by chemical substances, such as cuticular hydrocarbons (CHCs). In bees, volatile chemicals released by females are responsible for attracting mating partners at greater distances, in turn these individuals aggregate at the entrance of their colonies, where the copulation events take place. However, the proximal mechanisms that promote such behaviors are still not well explored. The present study aimed to determine whether two factors, age and social context in which gynes of the stingless bee Scaptotrigona aff. depilis are living, are involved in the process of attracting males. The main gols were: (1) Investigate whether gynes produced in vitro have a different chemical composition over their cuticles and within their Dufour gland depending on their age; (2) Check the fitness of gynes with different ages through sexual attractiveness bioassays; (3) Explore whether the social context in which a female is in contact with affects the chemical composition of their cuticular layer and Dufour gland; (4) Examine how the social context affects the fitness of gynes and inseminated queens; (5) Investigate how social context and age influence the social attractiveness of gynes, as well as the chemical composition of their cuticle and Dufour gland. Females of S. aff. depilis were produced in vitro and it was expected that their age and the social context they were exposed would have a direct impact on their sexual attraction ontogeny. According to the results, gynes of S. aff. depilis produced in vitro do not emerge attractive, however, once they become attractive, they remain like that for at least 21 days, additionally, their attractiveness levels are similar through their adulthood. The social context has an impact over their sexual attractiveness (at least in a social context in which gynes are likely competing among each other), besides that, it also affects the chemical composition of the cuticle and Dufour gland in gynes with the same age. The sexual attractiveness of gynes is not ceased after they copulate. Furthermore, the chemical compounds present over the cuticle and in the Dufour gland of gynes with different ages are different. These results mean that even in gynes produced in vitro the chemical compounds vary according to age, which is likely to be involved with their sexual attractiveness or merely indicate their reproductive status. The Dufour gland compounds likely contribute with the chemical composition of the gynes cuticle and also with their sexual attractiveness. (AU) | |
| FAPESP's process: | 19/07885-4 - Ontogeny of sexual attractiveness in gynes of Scaptotrigona aff. depilis (Hymenoptera, Apidae, Meliponini) |
| Grantee: | Jéferson Pedrosa dos Santos |
| Support Opportunities: | Scholarships in Brazil - Master |