TY - JOUR
T1 - Assessing the Occurrence of Sexual Segregation in Spider Monkeys (Ateles geoffroyi yucatanensis), Its Mechanisms and Function
AU - Hartwell, Kayla S.
AU - Notman, Hugh
AU - Bonenfant, Christophe
AU - Pavelka, Mary S.M.
N1 - Funding Information:
Acknowledgments Thanks to Dr. Gil and Lillian Boese from the Zoological Society of Milwaukee and the Foundation for Wildlife Conservation for permission to work in RCNR and Birds without Borders/Aves sin Fronteras for their ongoing support and assistance with this project. Stevan Reneau in particular spent hundreds of hours assisting in data collection. Sharon Matola of the Belize Zoo is responsible for initiating the discussions that led to the establishment of this project in 2007, and we thank the staff at the Belize Zoo and Tropical Education Center for ongoing assistance of all kinds.We thank Kathreen Ruckstuhl for putting us in touch with Christophe Bonenfant and launching what is proving to be a very productive collaboration. We also thank Brittany Dean for assisting in data collection. This research was supported by the Natural Sciences and Engineering Research Council of Canada, the National Geographic Society, the University of Calgary, and Athabasca University. We also thank two anonymous reviewers and the editor for their careful and thoughtful reviews and constructive feedback.
PY - 2014/4
Y1 - 2014/4
N2 - Sexual segregation is a recognized dimension of the socioecology of many vertebrates, but it has not been systematically examined in primates. We investigated temporal patterns of sexual segregation in spider monkeys (Ateles geoffroyi yucatanensis) using a test that distinguishes sexual segregation from aggregation and random association between the sexes. We further investigated how sexual segregation varies over time as a function of food availability, and then tested other possible factors that might be causally linked to sexual segregation in spider monkeys. We predicted that male philopatry and cooperative territorial defence leads to sexual dimorphism in behavior, which in turn creates different optimal energetic requirements for males and females as reflected in differing activity budgets and diet. We investigated sexual segregation in a group of 33-35 spider monkeys at Runaway Creek Nature Reserve in Belize over 23 mo in 2008-2009. We used the sex compositions of subgroups recorded in scan samples to test the occurrence of sexual segregation at monthly and biweekly time scales.We found that males and females were significantly segregated in 15 out of the 23 mo of the study, and that periods of nonsegregation coincided with months of low food availability. The sexes differed significantly in activity and diet; males spent more time traveling, and less time resting and feeding than females, and they had a higher proportion of ripe fruits in their diets than did females. We propose that sexual segregation in spider monkeys is primarily a form of social segregation that results from males and females pursuing optimal dietary and behavioral strategies to satisfy sex-specific energetic demands. We further suggest that sexual segregation represents an important constraint on fission-fusion dynamics that should be considered when assessing the potential for variability in subgroup composition.
AB - Sexual segregation is a recognized dimension of the socioecology of many vertebrates, but it has not been systematically examined in primates. We investigated temporal patterns of sexual segregation in spider monkeys (Ateles geoffroyi yucatanensis) using a test that distinguishes sexual segregation from aggregation and random association between the sexes. We further investigated how sexual segregation varies over time as a function of food availability, and then tested other possible factors that might be causally linked to sexual segregation in spider monkeys. We predicted that male philopatry and cooperative territorial defence leads to sexual dimorphism in behavior, which in turn creates different optimal energetic requirements for males and females as reflected in differing activity budgets and diet. We investigated sexual segregation in a group of 33-35 spider monkeys at Runaway Creek Nature Reserve in Belize over 23 mo in 2008-2009. We used the sex compositions of subgroups recorded in scan samples to test the occurrence of sexual segregation at monthly and biweekly time scales.We found that males and females were significantly segregated in 15 out of the 23 mo of the study, and that periods of nonsegregation coincided with months of low food availability. The sexes differed significantly in activity and diet; males spent more time traveling, and less time resting and feeding than females, and they had a higher proportion of ripe fruits in their diets than did females. We propose that sexual segregation in spider monkeys is primarily a form of social segregation that results from males and females pursuing optimal dietary and behavioral strategies to satisfy sex-specific energetic demands. We further suggest that sexual segregation represents an important constraint on fission-fusion dynamics that should be considered when assessing the potential for variability in subgroup composition.
KW - Ateles
KW - Fission-fusion dynamics
KW - Sex differences
KW - Sexual segregation
KW - Social organization
UR - http://www.scopus.com/inward/record.url?scp=84897576445&partnerID=8YFLogxK
U2 - 10.1007/s10764-013-9746-0
DO - 10.1007/s10764-013-9746-0
M3 - Journal Article
AN - SCOPUS:84897576445
SN - 0164-0291
VL - 35
SP - 425
EP - 444
JO - International Journal of Primatology
JF - International Journal of Primatology
IS - 2
ER -