Eu sei quem você é: fêmeas de anuros (Pristimantis ramagii) percebem e discriminam cantos de machos exóticos congêneres alopátricos

Abstract

In Anuran Amphibians, acoustic recognition is closely linked to reproductive function, and may act as a prezygotic barrier. In this scenario, songs of exotic species can interfere with the interaction of native species when in a situation of acoustic convergence. Researches indicate that ovate females who have already gone through a lived acoustic experience can mitigate the harmful consequences of distractions or revulsions to ambient noises. However, although there is already an understanding of the role of sound recognition in female sexual selection, the literature still needs to address the relationship between phonotaxy and female age, especially in natural environments. In view of the information presented, we conducted a field study with the purpose of investigating whether there is any correlation between the age/experience of female frogs and their response to stimuli created from the song of a native male, an exotic male and a control stimulus. The native species used was Prisimantis ramagii, endemic to the Atlantic Forest in northeastern Brazil, while the exotic species was Pristimantis koehleri, endemic to the Amazon Forest in Bolivia. We expect that (i) older/experienced females would have more positive behavioral responses to the native male; (ii) older/experienced females would have more negative behavioral responses to the exotic male stimulus. For this research, we used 30 sexually mature and ovate females of P. ramagii, which were identified individually, so that their ages were estimated via rostrum-cloacal length. The experiment involved playing the different sound stimuli while simultaneously observing the females. The results indicated that the different types of stimuli had an impact on the attractiveness and response latency to the phonotaxy of the tested females, with the native stimulus being the most attractive and with the lowest response latency. Surprisingly, female experience did not influence attractiveness and response latency to stimuli. These findings suggest that female anuran amphibians may have learning limitations during the development of their behavioral acoustic recognition skills. This can be attributed to the influence of the group's short lifespan, leading them to rely more on innate recognition.