Type
Text
Type
Dissertation
Advisor
Doran-Sheehy, Diane M | Koenig, Andreas | Janson, Charles | Wright, Patricia | Watts, David.
Date
2015-08-01
Keywords
aggression, diet, dominance, nutrition, rank, socioecological | Physical anthropology
Department
Department of Anthropology.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76944
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
In wild primates, feeding competition is believed to influence female social relationships, patterns of dispersal, energy gain, and reproductive success. When high– quality foods are distributed in monopolizable patches, high– ranking females can use aggression to exclude low– ranking females from patches, thereby consistently gaining more food. Rank– related differences in female energy gain are expected to arise, and selection for aggression is thought to lead to unidirectional female agonistic relationships and a linear dominance hierarchy. The social and energetic effects of within– group contest competition have been extensively documented in small– bodied monkeys living in cohesive groups. However, the impact of contest competition is less clear among large– bodied primates with reduced predation pressure and relaxed group cohesion. To address this question I examined the social, nutritional, and energetic consequences of increased frugivory (a proxy for high– quality monopolizable foods) in wild western gorillas compared to published records for mountain gorillas. Focal follows of adult females in one social group of western gorillas (Gorilla gorilla) were conducted during a 14– month period between 2004 and 2006 at the Mondika Research Center in the Central African Republic and Republic of Congo. Results reveal that the diet (by wet weight) of western gorilla females contained nearly three times more fruit compared to mountain gorillas (41– 43 % and ≤ 15 %, respectively) and that western gorilla fruits contained more total non-structural (‘ simple’ ) carbohydrates than mountain gorilla fruits. Most female aggression (89 %, n = 551 events) in western gorillas occurred over access to food. Decided dominance relationships were indicated in a relatively high proportion (53 – 60 %) of female western gorilla dyads based on aggression, and females could be ordered into a steep and linear dominance hierarchy. Rank, however, did not influence overall energy intake, suggesting that within– group contest competition has minimal fitness consequences in western gorillas. Reduced group cohesion in western gorillas may be an important factor allowing females to spread out and avoid contest competition. Implications of dietary and nutritional differences between gorillas occupying lowland forests versus montane habitats are discussed with regard to differing life history strategies between the two species. | 209 pages
Recommended Citation
Lodwick, Jessica Lee, "Links between foraging strategies, feeding competition, and female agonistic relationships in wild western gorillas (Gorilla gorilla)" (2015). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2815.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2815