Attacks on neonates by a male mangabey (Cercocebus atys)
Curt D Busse1, Thomas P Gordon1
1Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia.
Insights
An alpha male sooty mangabey (Cercocebus atys) exhibited infanticide, attacking three infants. This behavior occurred in a stable group, differing from typical infanticide patterns in primates.
Area of Science:
- Primate Behavior
- Ethology
- Reproductive Strategies
Background:
- Long-term study of a captive social group of sooty mangabeys (Cercocebus atys).
- Observation of aggressive behavior by an adult male towards infants and mothers.
- Focus on reproductive dynamics within stable social structures.
Purpose of the Study:
- To document and analyze instances of infanticide in a captive sooty mangabey group.
- To investigate the behavioral patterns preceding and during infant attacks.
- To contextualize these observations within existing models of primate infanticide.
Main Methods:
- Long-term observational study of a captive sooty mangabey social group.
- Detailed recording of aggressive incidents, focusing on attacks on neonates.
- Behavioral analysis of the alpha male's interactions with mothers and infants.
Main Results:
- The highest-ranking adult male attacked three out of 13 infants, with direct attacks on mother-infant pairs.
- Attacks involved grabbing infants from mothers and biting the head; one infant was fatally injured.
- Preceding behavior included persistent stalking of mother-infant pairs, starting shortly after birth.
Conclusions:
- Infanticide by a resident alpha male occurred in a stable social group, challenging some existing theories.
- The male had recently attained alpha status, suggesting a potential link to reproductive competition.
- Observed behaviors provide new data for understanding infanticide dynamics in primates, particularly in stable social contexts.
Abstract:
Aggressive behavior by an adult male toward selected infants and their mothers was observed during a long-term study of reproduction in a captive social group of sooty mangabeys (Cercocebus atys). The highest-ranking adult male in this group was observed to attack and bite three neonates out of a total of 13 infants born in 1982. All three attacks were directed attacks in which infants were grabbed from their mothers and bitten in the head. The first infant was fatally injured; the other two probably would have sustained fatal wounds had the male's canines not been blunted beforehand and had observers not intervened. The attacks were preceded by a pattern in which the male persistently stalked or chased the mother-infant pairs, a behavior first observed in the hours immediately following parturition. Unlike attacks in wild baboon groups following male immigration, these attacks on infants occurred in a stable social group in which the male attacker had been a lifelong resident. This male, however, had gained alpha rank only 3 months before attacking the first infant. These attacks, in the context of other evidence of aggression and wounding, are discussed relative to current models of infanticide in primates.
