Two Breeding Females within Free-Living Groups May Not Always Indicate Polygyny: Alternative Subordinate Female Strategies in Common Marmosets (Callithrix jacchus)

• Published in: Folia primatologica Vol. 76; no. 1; pp. 10 - 20
• Main Authors: Arruda, M.F, Araújo, A, Sousa, M.B.C, Albuquerque, F.S, Albuquerque, A.C.S.R, Yamamoto, M.E
• Format: Journal Article
• Language: English
• Published: The Netherlands Brill 01.01.2005; Karger; S. Karger AG
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Autoecology; Biological and medical sciences; Callithrix - physiology; Callithrix jacchus; Female; Females; Fundamental and applied biological sciences. Psychology; Male; Mammalia; New World monkeys; Primate behaviour; Primates; Primatology; Reviewed Article; Sexual Behavior, Animal - physiology; Sexual reproduction; Social relations; Vertebrata; South America; Brazil; America; Mating systems; Reproductive strategies; Marmoset; Callithrix jacchus; Extra-group copulations; Social group; Sexual behavior; Breeding behavior; Mating; Mating system; Reproduction; Vertebrata; Mammalia; Primates; Simioidea; Female; Strategy; Field study; Polygyny
• ISSN: 0015-5713; 1421-9980
• DOI: 10.1159/000082451

The mating system of callitrichids has been reported to be monogamous, polygynous and polyandrous. In Callithrix jacchus, groups with 2 breeding females and groups with 1 breeding female have been reported. Our purpose was to evaluate the occurrence of occasional reproduction by subordinate females in free-ranging C. jacchus groups characterized as monogamous. Four groups were monitored at a field site of IBAMA-Brazil for between 20 and 72 months. We recorded the birth of 7 sets of twins to subordinate females that had never reproduced before. Sexual activities were recorded opportunistically: dominant females copulated with only the resident male, while subordinates copulated with extra-group males. We suggest these were essentially monogamous groups that occasionally had 2 reproductive females. Between-group copulations seem to be an alternative strategy used by the subordinates. Despite the costs, there would probably be benefits as a result of scanning for vacancies for reproductive positionsin neighbouring groups and the establishment of ties with extra-group males that might become a reproductive partner in the future.