Mating strategies and parental care in glassfrogs (Amphibia Anura Centrolenidae)

Author(s)

Anyelet Valencia Aguilar

• Document type: Doctoral Thesis
• Press: Rio Claro. 2020-03-11.
• Institution: Universidade Estadual Paulista (Unesp). Instituto de Biociências. Rio Claro
• Defense date: 2020-03-02
• Advisor: Cynthia Peralta de Almeida Prado

Abstract

Many species in the Centrolenidae family, know as glassfrogs, exhibit paternal care of eggs. Although parental care promotes offspring survival, it may impose survival and mating cost; hence, males should intensify or weaken resource allocation between its fitness’ components. Furthermore, anuran males compete to attract females, but since it is an energetically demanding activity, in some cases individuals use some tactics to offset these costs and gain access to mates. In this thesis, I studied different aspects of the paternal care and mating strategies in glassfrogs species, which were separated in four chapters. In chapter 1, we made field observations and conducted behavioral experiments in attending and non-attending males of the glassfrog Hyalinobatrachium cappellei to examine the importance of attending activities on offspring survival, as well as the effects of predation risk on male’s behavior. We also assessed how parental care influences time allocation in males’ activities. We found that care activities do not affect male’s mating success and that paternal care is crucial to avoid embryo dehydration. Besides, our results show that although attending males are more risk tolerant, they will prioritize their own survival, even with negative effects on offspring, when the threat reaches a certain threshold. In chapter 2, we examined female mate preference in H. cappellei. Our results indicate that females of H. cappellei do not select males based on body condition, call persistence, or territory characteristics. Instead, females choose males based on care status; attending males had higher chance of attracting new females and gain new clutches. Additionally, we also found that males adjust their parental care effort in response to genetic relatedness, by caring only for their own offspring; however, they may remain close to unrelated clutches as a strategy to attract females and increase chances of successful mating. In chapter 3, we experimentally investigated the existence of allopaternal care in two centrolenid species, Hyalinobatrachium chirripoi and Centrolene peristicta, as well as the possible costs and benefits of this behavior. Attending males of both species males adopted unrelated clutches, whereas non-attending males abandoned their territories when unrelated clutches were placed close to them. Contrary to our expectations, once males adopted the unrelated clutches, they cared for all the eggs in their territories with a similar frequency. Our finding suggest that alloparenting in glassfrogs only occurs in males that already have clutches of their own and, most likely, cannot distinguish unrelated clutches. Finally, in chapter 4, we tested whether glassfrog males that care for their offspring have smaller relative testes volume compared with species that do not exhibit paternal care. We collected data on testis size of breeding frogs using information from specimens we have collected, as well as from museum specimens, and literature. For the 26 species of glassfrogs included in our data set, we found that attending males tend to have smaller testes compared with non-attending males in glassfrogs. Besides, no significant effects of clutch size on testes size were detected. These results suggest that testes size may also vary in response to a pots-fertilization investment, such as parental care. (AU)

• FAPESP's process: 16/05070-5 - Evolution of parental care in glassfrogs (Amphibia: Anura: Centrolenidae)
• Grantee: Anyelet Valencia Aguilar
• Support Opportunities: Scholarships in Brazil - Doctorate