Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California.
Am J Primatol. 1981;1(4):439-452. doi: 10.1002/ajp.1350010409.
The behavioral and hormonal responses of squirrel monkeys of the Bolivian and Guyanese subspecies were compared after a group formation procedure. Two groups of each subspecies, consisting of five females and three males (later reduced to two) were observed daily during the week of group formation and for nine weeks following removal of a single male from each group. Measures of plasma cortisol were examined in the females after the initial group formation and after the groups were reduced by one male. The levels of plasma testosterone were assessed in all the males during the initial week of group formation. Linear dominance hierarchies were determined both within and across the sexes in both subspecies. The frequency and directionality of low-level aggressive interactions indicated that females of the Bolivian subspecies were dominant to the males, while the males of the Guyanese subspecies ranked over all the females. Additionally, the Bolivian squirrel monkey females showed an elevation of plasma cortisol on the day of group formation, which declined 48 hr later, then reelevated after the groups were reduced by one male and declined gradually over a nine-week period. Guyanese females showed little change in cortisol levels during both periods. This suggests fundamental hormonal, as well as behavioral, differences between the two subspecies. The change in plasma testosterone levels in the males during the initial week of group formation was positively correlated with social status. Furthermore, differences in the dynamics within individual groups for each subspecies were reflected by the levels of plasma cortisol of the female members.
比较了玻利维亚亚种和圭亚那亚种的松鼠猴在群体形成程序后的行为和激素反应。每组包括五只雌性和三只雄性（后来减少到两只）的两个亚种群体，在群体形成的一周内以及在从每组中移除一只雄性后的九周内每天进行观察。在初始群体形成后以及在减少一只雄性后，对雌性的血浆皮质醇进行了测量。在初始群体形成的第一周，对所有雄性的血浆睾丸激素水平进行了评估。在两个亚种的雌雄两性中都确定了线性优势等级制度。低水平攻击性相互作用的频率和方向性表明，玻利维亚亚种的雌性对雄性具有优势，而圭亚那亚种的雄性则对所有雌性具有优势。此外，玻利维亚松鼠猴雌性在群体形成当天的血浆皮质醇升高，48 小时后下降，然后在减少一只雄性后再次升高，并在九周内逐渐下降。圭亚那雌性在这两个时期的皮质醇水平几乎没有变化。这表明两个亚种之间存在基本的激素和行为差异。雄性在群体形成的初始周内的血浆睾丸激素水平的变化与社会地位呈正相关。此外，每个亚种个体群体内部的动态差异反映在雌性成员的血浆皮质醇水平上。
