摘要:

During a long-term study of wild Thomas’s langurs (Presbytis thomasi), the adult male of one of the bisexual study groups, group M, suddenly disappeared. Just after the adult male’s disappearance, the females of group M actively avoided other groups and sometimes formed subgroups. Infants were attacked by extra-group males and 1 infant disappeared. After about 2 months, the females initiated affiliative interactions with males of neighbouring groups. Aggressive interactions between females of group M and females of other groups were also observed. Females of group M did not leave their home range in spite of efforts by adult males to lead them away. After about 4.5 months, a former all-male band member joined group M. The coincidences of this case suggest that increased infanticide risk, increased food competition, loss of knowledge of the home range and loss of established social relationships could be important constraints on female transfer. A comparison with 5 other studies of 1 -male groups in which the adult male disappeared showed that proximate factors, such as the presence of infants, the size of neighbouring groups and the presence of extra-group males, influence female decisi

ISSN:0015-5713    

DOI:10.1159/000157220

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

In order to quantify the relative position and extent of the nasal and orbital openings in hominoid primates, a new methodology based on image analysis was developed and applied to a series of 134 hominoid skulls (52 Gorilla gorilla; 30 Pan troglodytes; 44 Homo sapiens, and, as comparison material, 8 Pongo pygmaeus). The areas and the centres of area of the orbital and nasal openings were determined automatically. The orbitonasal triangle connecting these three centres of area was then constructed. This triangle was used to quantify the elongation of the face. It was most elongated in Gorilla, shortest in the human species and intermediate in Pan; the elongation in Pongo was close to that in Gorilla. The proportions of the areas of the orbital and nasal openings in the face were related to the extent of the bony structures of the midface and were thus used to quantify the facial robustness. A robust face was demonstrated in Gorilla, but a gracile face in the human species. Robusticity in Pan was intermediate.

ISSN:0015-5713    

DOI:10.1159/000157221

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0015-5713    

DOI:10.1159/000157222

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0015-5713    

DOI:10.1159/000157223

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0015-5713    

DOI:10.1159/000157224

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0015-5713    

DOI:10.1159/000157225

出版商:S. Karger AG    

年代:1996

数据来源: Karger

ISSN:0015-5713    

DOI:10.1159/000157219

出版商:S. Karger AG    

年代:1996

数据来源: Karger