Abstract # 165:

Scheduled for Saturday, June 23, 2007 08:45 AM-09:00 AM: Session 15 (North Main Hall E) Oral Presentation

Grooming Payment for Infant Handling in Long-tailed Macaques (Macaca fascicularis)

M. D. Gumert
Hiram College, Hiram, OH 44234, USA
     Social markets may be a proximate influence on grooming exchange in primates. In some situations, grooming can be directly associated with the receipt of other social acts or with increased access to social partners. In many primates, including long-tailed macaques, females are attracted to infants and groom mothers with infants more than other females. Grooming in this context may be payment to the mother to touch, groom, or hold an infant. A study was conducted on 18 females and 24 infants investigating all grooming bouts that included infant handling during a 13-month study in Kalimantan, Indonesia. These bouts were labeled grooming-infant handling interchanges because of the sequential association between the two acts. Ten-minute focal samples and post-grooming (PG) samples were also collected. PG samples were observed on a mother immediately following female-to-mother grooming. A comparison of PG and baseline samples using a paired-t-test [a=0.05] showed that grooming significantly increased the frequency of infant handling towards a mother’s infant. Regression analysis [a=0.05] of the sample of grooming-infant handling interchanges showed that there was a significant negative relationship between grooming duration and the ratio of infants per female around an interchange. Rank also significantly influenced grooming duration. A t-test [a=0.05] showed that up-rank bouts were significantly longer than down-rank bouts. These results indicate the role of grooming, partner supply, and dominance in an infant market.