Inbreeding risk, avoidance and costs in a group-living primate, Cebus capucinus

• Published in: Behavioral ecology and sociobiology Vol. 70; no. 9; pp. 1601 - 1611
• Main Authors: Godoy, Irene, Vigilant, Linda, Perry, Susan E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer 01.09.2016; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Age; Animal Ecology; Behavioral Sciences; Biomedical and Life Sciences; Cebus capucinus; Dyadics; Females; Genetics; Grants; Inbreeding; Inbreeding depression; Infants; Life Sciences; Monkeys; Monkeys & apes; Mothers; Offspring; Original Article; Primates; Siblings; Zoology; Primates; Inbreeding avoidance; Capuchin monkeys; Inbreeding depression
• DOI: 10.1007/s00265-016-2168-1
• ISSN: 0340-5443

Documenting inbreeding and its potential costs in wild populations is a complicated matter. Early infant death before genetic samples can be collected limits the ability of researchers to measure fitness costs, and pedigree information is necessary to accurately estimate relatedness between breeding individuals. Using data from 25 years of research from the Lomas Barbudal Capuchin Monkey Project, and a sample of 109 females that have given birth, we find that despite frequent co-residency of adult opposite-sexed individuals, capuchins produce offspring with close kin (i.e., related at the halfsibling level or higher) less often than would be expected in the absence of inbreeding avoidance. We do not find support for alternative, non-behavioral explanations for this pattern and thus argue for mate choice. Furthermore, we find evidence for fitness costs among inbred animals in the form of delayed female age at first birth but not significantly higher juvenile mortality. Further research is necessary in order to determine the mechanisms by which individuals develop sexual aversion to close kin. Through a combination of demographic records, maternal pedigrees, and genetically determined paternity, this study provides a detailed study of inbreeding and inbreeding avoidance in a well-studied mammal population. This study provides (1) evidence that capuchin monkeys avoid mating with close kin at both the level of parent-offspring and half sibling and (2) evidence of fitness costs to inbreeding in the form of delayed first age at reproduction.