Clarke M R
Delta Regional Primate Research Center, Tulane University, Covington, La.
Folia Primatol (Basel). 1990;54(1-2):1-15. doi: 10.1159/000156422.
A 22-month field study was carried out on free-ranging mantled howlers in Costa Rica. Six female and 5 male infants were observed systematically from birth until they died, left the group, or the study ended. Interaction patterns, activity patterns, and proximity data were analyzed from 703 h of focal observations and 753 h of ad lib observations. Developmental trends in weaning and nonmother care were associated with mothers' feeding patterns, suggesting an increase in maternal feeding efficiency. As howler immigration patterns resulted in groups of adults of low relatedness, analyses based on social bonding or kin selection were inappropriate, and socialization patterns instead appeared to prepare howler infants to respond predictably in an adult world. Females, which were more sociable as adults, were also more sociable as infants, initiating interactions and reacting positively. They also exhibited less weaning stress than males. Males, which were forced out of the group sooner, remained solitary longer, and primarily interacted with adult females as adults, were forced to be independent sooner, reacted negatively to interactions, and ceased interacting with adult males by 3 months of age. Ecological constraints on development could not be determined from this study, although there was no evidence for developmental trends being influenced by predator stress.
在哥斯达黎加对自由放养的鬃毛吼猴进行了为期22个月的实地研究。从出生起就对6只雌性和5只雄性幼猴进行系统观察，直至它们死亡、离开群体或研究结束。从703小时的焦点观察和753小时的随意观察中分析了互动模式、活动模式和接近度数据。断奶和非母亲照料的发育趋势与母亲的喂养模式有关，这表明母亲的喂养效率有所提高。由于吼猴的迁徙模式导致成年个体之间亲缘关系较低的群体形成，基于社会联系或亲缘选择的分析并不合适，相反，社交模式似乎使吼猴幼崽能够在成年世界中做出可预测的反应。成年后更善于社交的雌性幼猴在幼年时也更善于社交，会主动发起互动并做出积极反应。它们断奶时的压力也比雄性幼猴小。雄性幼猴更早被赶出群体，独自生活的时间更长，成年后主要与成年雌性互动，它们被迫更早独立，对互动反应消极，到3个月大时就停止与成年雄性互动。尽管没有证据表明发育趋势受到捕食者压力的影响，但本研究无法确定生态对发育的限制因素。
