Our knowledge about genetic mating systems and the underlying causes for and consequences of variation in reproductive success has substantially improved in recent years. When linked to longitudinal population studies, cross-generational pedigrees across wild populations can help answer a wide suite of questions in ecology and evolutionary biology. We used microsatellite markers and exhaustive sampling of two successive adult generations to obtain population-wide estimates of individual reproductive output of males and females in a natural population of the Neotropical frog Allobates femoralis (Aromobatidae), a pan-Amazonian species that features prolonged iteroparous breeding, male territoriality and male parental care. Parentage analysis revealed a polygynandrous mating system in which high proportions of males (35.5%) and females (56.0%) produced progeny that survived until adulthood. Despite contrasting reproductive strategies, successfully reproducing males and females had similar numbers of mating partners that sired the adult progeny (both sexes: median 2; range 1-6); the numbers of their offspring that reached adulthood were also similar (both sexes: median 2; range 1-8). Measures of reproductive skew indicate selection on males only for their opportunity to breed. Reproductive success was significantly higher in territorial than in nonterritorial males, but unrelated to territory size in males or to body size in both sexes. We hypothesize that female polyandry in this species has evolved because of enhanced offspring survival when paternal care is allocated to multiple partners.

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Phonotactic approaches by 17 male Allobates femoralis were videotaped and analysed in terms of spatial and temporal patterns to assess this species' ability to localise sound. Jump angles of consecutive jumps and the straightness of paths were measured to quantify the accuracy of approach. The effect of interbout intervals on phonotactic approach was examined by comparing movement parameters of two tests, using a standard call with interbout intervals, and a continuous call without interbout intervals. Phonotactic approach occurred almost exclusively during calling bouts. Interbout intervals interrupted movement and did not alter the accuracy of approach. Our results suggest that only the calling bouts, but not the silent interbout intervals, play a crucial role for male phonotaxis in this species. Furthermore, anuran phonotactic approach is not strictly axis-alternated and, thus, not appropriately described by the generally used term 'zig-zagging'.