Journal of Chemical Ecology. Vol. 23. No. 11. 1997 DIFFERENTIAL DISPLAY OF INVESTIGATIVE BEHAVIOR PERMITS DISCRIMINATION OF SCENT SIGNATURES FROM FAMILIAR AND UNFAMILIAR SOCIALLY DOMINANT FEMALE MARMOSET MONKEYS (Callithrix jacchus) TESSA E. SMITH, 1'* DAVID H. ABBOTT,2 ANDREW J. TOMLINSON,3 and JERZY A. MLOTKIEWICZ4 1 Nebraska Behavioral Biology Group & Department of Psychology University of Nebraska, Omaha, Nebraska 68182 2 Wisconsin Regional Primate Research Center and Department of Obstetrics and Gynecology University of Wisconsin, Madison, Wisconsin 53715 *The Biomedical Mass Speclrometry Facility Department of Biochemistry and Molecular Biology Mayo Clinic, Rochester, Minnesota 55905 *Dalgety Food Technology Center, Dalgety PLC Station Rd, Cambridge, UK (Received April 4, 1996; accepted July 5, 1997) Abstract—The hypothesis was tested that marmosets have differential displays of investigatory behavior towards circumgenital scent marks from socially dominant females based on degree of familiarity. In a series of two-choice behavioral discrimination bioassays, dominant males together with subordi- nate and dominant females were presented concurrently with scent secretions from familiar versus unfamiliar dominant females, and their investigative behaviors towards the scent were recorded. Test animals directed significantly different amounts of investigative behaviors towards familiar versus unfamiliar scents when the scent stimuli involved complete circumgenital scent marks, glandular secretion only, or urine only. When animals discriminated between the two scent samples, they did so by directing significantly increased amounts of behavior to scent from unfamiliar females. Chemical cues promoting dif- ferential displays of behavior to familiar versus unfamiliar scents appeared to be volatile in nature and were effective in the scent mark for at least one day following deposition. The reliable ability of marmosets to consistently dis- criminate between odors from familiar versus unfamiliar dominant females provides strong circumstantial evidence that individual female marmosets have distinct chemical signatures. The ability of marmosets to discriminate the odor *To whom correspondence should be addressed. 2523 0098-0331/97/1100-2523/$12.50/0 © 1997 Plenum Publishing Corporation