Vocal Communication and Ontogeny of Foraging
Lisa G. Rapaport
This study began in October 1999 and is being funded by a five-year National Institute of Mental Health grant to Lisa Rapaport, through the University of New Mexico Anthropology Department. We are working out a collaborative agreement with Paula Procópio de Oliveira and her translocation team (Kierulff, Procópio de Oliveira, Rapaport & Ruiz-Miranda ) in the Reserva Biológica União. We are interested in the issues of alternative behavioral strategies used by offspring to obtain resources, caregiver-offspring conflict, and the relationship between trial and error versus social learning in regard to food acquisition and preferences.
We have had two primary study groups during the first year of the project (LB and Funil). We plan to collect data on three different groups of tamarins at União in 2001. We have seen exciting confirmation with regard to our conjectures about social foraging strategies as a function of age. Infants do appear to monitor adult foraging activities. As our study subjects entered the second half of their first year, they quickly traveled over ever-greater distances to commandeer food and foraging sites from older group members. We look forward to converting impressions into quantitative analysis as the sample size increases.
The project hired three field assistants (Marcio Moraes, Eraldo dos Santos and Rachel Tabet) and one housekeeper in late 1999. The project financed the reconstruction of one house in União Reserve. The NIMH project will use the house for the duration of the field study (which is planned to be 2-3 years).
We have chosen to conduct our experiments at the Centro de Primatologia do Rio de Janeiro (CPRJ). Within the next month or two, we will begin to augment the daily ration of 4-5 groups of Leontopithecus chrysomelas, and possibly Leontopithecus chrysopygus, at the CPRJ to encourage reproduction. Food transfer experiments, similar to those I conducted for my dissertation, will be performed on these groups to determine how food familiarity interacts with age to influence food consumption and feeding preferences of immature lion tamarins.
Although we are interested in the nutritional content of foods eaten by immature golden lion tamarins, we have not been collecting samples of plant or animal foods. We are working out a collaboration with Paula Procópio de Oliveira to nutritionally analyze plant samples collected at the União Reserve. We are developing criteria to select those foods that regularly appear in the tamarin diet. We plan to determine not only caloric content but also percentages of fat, fiber, protein, calcium and phosphorus. Eleonora D'Avila Erbesdobler, a graduate student of Carlos Ruiz Miranda¹s at UENF, will begin caloric analysis of samples of tamarin plant foods collected in União.
Carlos Ruiz coordinated or adviser the following research: