Behaviour 2019
Loss of the father, not the mother, reduces infant survival in a pair-living, sexually monogamous primate
Alba T. Garcia de la Chica1, Carola Borries2, Eduardo Fernandez-Duque1,3,4. 1Owl Monkey Project-Fundación ECO, Formosa, Formosa, Argentina; 2Stony Brook University, Stony Brook, New York, United States; 3Yale University, New Haven, Connecticut, United States; 4University of FormosaY, Formosa, Formosa, Argentina

In group-living species infant survival has been associated with immigration of new individuals into the group. In pair-living species the replacement of one reproducing adult can influence infant survival through the effects of group instability and the loss of one parent. In these species paternal care is often required for infant survival and it may benefit males by enhancing their own offspring survival, future mating opportunities, and by reducing the energetic burden of females. I evaluated the relationship between the replacement of a biological parent and the age of death of 149 identified infants in wild pair-living sexually monogamous owl monkeys (Aotus azarae) from Argentina. The presence of a new male is associated with infants dying at younger ages. This association is stronger if the replacement occurs during their first year of life, when they are dependent on direct paternal care. New males do not seem to be more likely to sire infants the next season, nor is the help of males associated with a reduction of females’ energetic burden. My findings strongly suggest that paternal care may have evolved as a strategy for advancing the genetic benefits of male owl monkeys