Genetic mating system, population genetics and effective size of Saffron Finches breeding in southern South America

BENÍTEZ SALDÍVAR, MARÍA JULIANA; MIÑO, CAROLINA ISABEL; MASSONI, VIVIANA

GENETICA

SPRINGER

Lugar: Berlin; Año: 2019

0016-6707

Thraupidae(Tanagers and allies) show a remarkable array of behaviors, ecologies,morphologies and plumage colors, offering agreat opportunity to investigate the evolution of avian mating strategies. Wecharacterize the population genetics and mating systemof Sicalis flaveola pelzelni, a socially monogamous Neotropicalsongbird with biparental care. We found moderate to high levels of neutral genetic variation,similar across three breeding seasons, consistent with large and stablepopulations, and no temporalgenetic structure. Parentage analyses of 114 adults and 198 nestlings (54nests) revealed 31.8 % of extra-pairoffspring (EPO) and 51.8% of broods with at least one extra-pair chick.Extra-pair paternity (EPP) rates varied across seasonsand were significantly higher in 2014 /2015. Neither breeding synchrony norpair genetic relatedness was significantly associatedto EPP rates. Males paired with females in nests with and without EPO wereequally heterozygous, and EPO were significantlyless heterozygous than within-pair offspring, not supporting the ?indirectgenetic benefits? hypotheses. Females weremore related to their extra-pair mates than to their social mates, notsupporting the ?inbreeding avoidance? hypothesis. The non-monogamous genetic mating systemuncovered here seems not to lower the effective size of the population, which was higher than the sample size of adultbreeders. We report and discuss possible cases of quasi-parasitism, asindicated by maternityexclusion patterns. We contribute novel information to expand the knowledgeabout the largely unexplored genetic matingsystems of Thraupidae. Our findings also set the stage for further studiesexamining if plumage coloration or song traitspredict paternity gain or loss in Saffron Finches.