摘要:

AbstractReproductive activity is limited to only one female in many species of callitrichid primates (marmosets and tamarins): daughters and subordinate females do not produce offspring. A suppression of ovulatory cyclicity is responsible for the lack of reproductive activity in three species of callitrichids studied to date. This study evaluated the endocrine status of golden lion tamarins (Leontopithecus rosalia) housed as daughters or sons in family groups and of individuals housed in isosexual peer groups. Daughters 17 months of age and older and a subordinate female had high levels of estrogen excretion. Mean levels of estrogen excretion in these females were similar to those of nonpregnant, breeding adult females (17.14 ± 6.82 versus 11.93 ± 6.33 μg/mg creatinine, respectively). Estrogen profiles were similar to those of breeding adult females, with sinusoidal cycles in estrogen excretion. Younger daughters in family groups (10 and 12 months old) showed markedly lower levels of estrogen excretion (0.84 ± 0.58 μg/mg creatinine). Estrogen profiles lacked the sinusoidal nature of cycles in older daughters and breeding females, and elevations in estrogen excretion occurred frequently and remained elevated for 1 or 2 days. Plasma testosterone levels in males varied widely, but mean concentrations did not differ among males housed in different social conditions. These results suggest that older daughters and subordinate females may be capable of expressing normal ovarian function in the presence of a breeding adult female. This finding may account for two unusual observations in the lion tamarin: the high level of female‐female aggression and the presence of groups in the wild with more than one actively breeding

ISSN:0275-2565    

DOI:10.1002/ajp.1350180202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe activity budgets of individual orangutans were investigated at the Kutai Reserve, Indonesia. Activity profiles within and between individuals were compared to examine monthly variations in feeding patterns, potential energetic constraints imposed by large body size and parturition, and the costs of sociality. Animals showed monthly changes in travelling, feeding, and resting patterns. Monthly increases in travelling and feeding were associated with marked reductions in the time spent resting. Inter‐individual variations in activity budgets did not exist among animals of the same age‐sex class. Activity patterns differed, however, as a function of age and sex. Adult females and subadult males travelled and fed significantly longer than an adult male. Parturition had predictable effects on activity; one female reduced her feeding and travelling immediately following parturition. Adult male orangutan sociality appears to be limited by travel costs. Associations with females forced a male orangutan to travel significantly more compared with periods in which he was solitary. The male did not lose an appreciable amount of time feeding when accompanying a fem

ISSN:0275-2565    

DOI:10.1002/ajp.1350180203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractAn adult female ringtailed lemur (Lemur catta) known not to have been pregnant showed spontaneous lactation in response to twin infants born to an unrelated female. The females had met only 7 months earlier, when they and two other unrelated adult females were released from separate locations in a forest enclosure to form a new social group. Three months after release, an adult male from an adjacent enclosure gained access to the new group for 1 day, the day of one female's estrus. No males had access to the females throughout the remainder of the breeding season. Within 2 weeks of the birth of the twins, one of the other adult females began carrying the infants frequently, typically one at a time. All three females were checked for lactation when the infants were two months old. Both their mother and the unrelated adult who had been carrying the infants were producing milk. The third adult female, who never carried either infant, had no milk. The third adult female, who never carried either infant, had no milk. This female, however, like the two maternal females, frequently attacked unfamiliar immigrating adult males when the males approached the infants. Potential implications of these observations concerning the social organization of ringtailed lemurs are discussed.

ISSN:0275-2565    

DOI:10.1002/ajp.1350180204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0275-2565    

DOI:10.1002/ajp.1350180201

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY