Abstract # 93:

Scheduled for Saturday, September 17, 2011 07:00 PM-09:00 PM: Session 14 (Salon G (Sixth Floor)) Poster Presentation


V. James-Aldridge1,2, L. Veliz1 and A. Fernandez1
1University of Texas - Pan American, Dept. of Psychology & Anthropology, Edinburg, TX 78539, USA, 2Gladys Porter Zoo

It is increasingly clear that variability in maternal competence among captive gorillas cannot be explained by birth type or rearing history. The three subjects of the present study, for example, had remarkably homogeneous backgrounds; they were full siblings, zoo born and nursery reared, and multiparous, yet only two of the three were successful mothers. We examined a total of 4363 minutes of behavioral data for the three females, collected from 2005 through 2009 by means of focal animal sampling, to search for clues to the differences in maternal competence. A difference that emerged was amount of contact with any other member of the group (n=12), with the successful mothers producing higher 5-year means than the unsuccessful mother, not only on a combined contact score (time in proximate contact plus time in physical contact), 72% and 59% of total observation time versus 14%, F(2,69)=17.38, p<.001; but also on a measure of only proximate contact that removed the effect of expected high levels of physical contact of successful mothers with infants, 26% and 28% of observation time versus 12%, F(2,69)=6.40, p<.003. Frequently described as “easygoing,” the unsuccessful mother was also described as being “bothered” by her infants. Her characteristic response to any stress was withdrawal, a pattern that could underlie both her low levels of social contact and her lack of maternal success.