TY - JOUR
T1 - From nest to nest - Influence of ecology and reproduction on the active period of adult gombe chimpanzees
AU - Lodwick, Jessica L.
AU - Borries, Carola
AU - Pusey, Anne E.
AU - Goodall, Jane
AU - McGrew, William C.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2004/11/10
Y1 - 2004/11/10
N2 - The time spent between sleeping periods, which is called the active period, has to accommodate all essential activities, including feeding, resting, social behavior, and reproduction. To minimize costs in terms of, e.g., predation risk, suboptimal foraging, or sleep deficiency, the active period of diurnal animals should be less than or equal to the daylight period. Thus, the active period of an animal should be shaped by local environmental conditions as well as by metabolic and reproductive demands. Chimpanzees, which exhibit reduced predator pressure and a flexible fission-fusion society, were chosen as a model to explore these links. We investigated the influence of sex, female reproductive status, dominance rank, and season on the duration of the active period of adult chimpanzees at Gombe National Park, Tanzania (1975-1992). Sexually nonreceptive females had shorter active periods compared to males, while receptive females had even longer active periods than males. Dominance rank did not influence the duration of the active period of nonreceptive females, but high- and middle-ranking males had shorter active periods compared to low-ranking males. Nonreceptive females exhibited longer active periods during the dry season than in the wet season. No seasonal effect was discovered for males, perhaps because they already had long active periods in the wet season. Nonreceptive females seem to be able to accommodate all essential activities in the daylight period available, probably because they live less socially than males. Thus, the active period does not reflect differences in female competitive abilities, but does reflect such differences in males. The duration of the active period appears to be a simple, reliable tool for exploring basic responses and constraints in animal societies.
AB - The time spent between sleeping periods, which is called the active period, has to accommodate all essential activities, including feeding, resting, social behavior, and reproduction. To minimize costs in terms of, e.g., predation risk, suboptimal foraging, or sleep deficiency, the active period of diurnal animals should be less than or equal to the daylight period. Thus, the active period of an animal should be shaped by local environmental conditions as well as by metabolic and reproductive demands. Chimpanzees, which exhibit reduced predator pressure and a flexible fission-fusion society, were chosen as a model to explore these links. We investigated the influence of sex, female reproductive status, dominance rank, and season on the duration of the active period of adult chimpanzees at Gombe National Park, Tanzania (1975-1992). Sexually nonreceptive females had shorter active periods compared to males, while receptive females had even longer active periods than males. Dominance rank did not influence the duration of the active period of nonreceptive females, but high- and middle-ranking males had shorter active periods compared to low-ranking males. Nonreceptive females exhibited longer active periods during the dry season than in the wet season. No seasonal effect was discovered for males, perhaps because they already had long active periods in the wet season. Nonreceptive females seem to be able to accommodate all essential activities in the daylight period available, probably because they live less socially than males. Thus, the active period does not reflect differences in female competitive abilities, but does reflect such differences in males. The duration of the active period appears to be a simple, reliable tool for exploring basic responses and constraints in animal societies.
KW - Pan troglodytes
KW - Rank
KW - Receptivity
KW - Seasonality
KW - Sex differences
UR - http://www.scopus.com/inward/record.url?scp=11144275752&partnerID=8YFLogxK
U2 - 10.1002/ajp.20076
DO - 10.1002/ajp.20076
M3 - Article
C2 - 15538768
AN - SCOPUS:11144275752
SN - 0275-2565
VL - 64
SP - 249
EP - 260
JO - American Journal of Primatology
JF - American Journal of Primatology
IS - 3
ER -