Correlation of CSF 5-HIAA concentration with sociality and the timing of emigration in free-ranging primates.
OBJECTIVE
The purpose of this study was to examine the relationship between behavior and serotonin in nonhuman primates.


METHODS
During a routine capture and medical examination, 26 adolescent male rhesus macaques (Macaca mulatta) were selected as subjects from a free-ranging population of 4,500 rhesus monkeys inhabiting a 475-acre sea island. Blood samples (N = 23) and CSF samples (N = 22) were obtained, and each subject was fitted with a radio transmitter collar for rapid location. The subjects were released into their social groups, and quantitative behavioral observations were made over a 3-month period.


RESULTS
CSF 5-hydroxyindoleacetic acid (5-HIAA) concentration was positively correlated with three measures of sociality: 1) total time spent grooming others, 2) total time spent in close proximity to other group members, and 3) mean number of neighbors within a 5-m radius. In addition, CSF 5-HIAA concentration was positively correlated with age at emigration from the natal group (in months).


CONCLUSIONS
In adolescent male rhesus macaques living in naturalistic settings, CSF 5-HIAA concentration is positively correlated with affiliative sociality. Rhesus males with low CSF 5-HIAA concentrations exhibit less social competence and emigrate from their social groups at a younger age than do males with higher concentrations of CSF 5-HIAA.
Mehlman
P T
PT
Laboratory Animal Breeders and Services, Inc., Yemassee, SC 29945, USA.
Higley
J D
JD
Faucher
I
I
Lilly
A A
AA
Taub
D M
DM
Vickers
J
J
Suomi
S J
SJ
Linnoila
M
M
D000367:Age Factors; D000374:Aggression / Q000502:physiology; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D015415:Biomarkers; D006120:Grooming / Q000502:physiology; D006702:Homing Behavior; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid*; D008253:Macaca mulatta / Q000134:cerebrospinal fluid* / Q000502:physiology; D008297:Male; D012701:Serotonin / Q000502:physiology*; D012919:Social Behavior; D013686:Telemetry
D015415:Biomarkers; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid