一项新的研究报告说，当涉及野外狒狒中的社会等级时，最高级别的或称“大哥大”的狒狒比第二等级的雄性狒狒有着更高的压力激素水平；这表明，处在社会的最高层可能会比过去认为的要付出更高的代价。 对大哥大级别的狒狒来说，它们的处于最高阶层的生活有着许多额外的待遇，其中包括能够更好地获得像食物和配偶这样的资源。 因此，人们一般假定，最高身份的益处会超越所付出的代价（除了在出现社会不稳定的时候，因为届时大哥大们常常必须用打斗来保护它们的地位或社会群体）。
成年雄性猴在监视其它猴活动时表示高度警惕
在过去的非人灵长类的研究中，获得最高身份的好处是明显的；在这些研究中，稳定组群中的高等级的雄性动物往往要比较低等级雄性动物的压力要少。 但是对野外狒狒激素水平的历时９年的一项研究，通过测试粪便样品中的激素水平，Jeanne Altmann及其同事发现，大哥大雄性狒狒与比低于它们的次高级别或称贝塔雄性狒狒相比有着更高的压力激素水平和较低的睾酮水平；即使在稳定的时期也是如此。
令人惊讶的是，大哥大雄性狒狒的压力激素水平与那些在低等级雄性中所发现的压力激素水平类似。 文章的作者猜测，造成这２个等级的雄性狒狒的压力原因可能是不同的：大哥大雄性狒狒的压力可能来自必须持续性地保持它们的地位及高度地参与交配活动，而狒狒社会中等级最低的雄性狒狒的压力则与获取食物和其它资源有关。 这些结果提示，处在动物（可能还有人）的社会中的最高地位可能具有独特的有待进一步探索的成本和收益。
生物探索推荐英文摘要
Pity your boss -- The stress of being at the top
Abstract：When it comes to social hierarchy in wild baboons, top-ranking or “alpha” males have higher stress hormone levels than second high ranking males, suggesting that being at the very top of society may be more costly than previously thought, a new study reports. Life at the top has many perks for alpha male baboons, including better access to resources like food and mates. Thus, it’s generally assumed that the advantages of top-status outweigh the costs (except in times of social instability, when alpha males usually have to fight to preserve their position or social group). The advantages of top-status are evident in previous non-human primate studies, where high-ranking males in stable groups tended to be less stressed than lower-ranked males. But a nine year study of hormone levels in wild baboons shows there’s more to this story. By testing hormone levels from feces samples, Jeanne Altmann and colleagues found that alpha males have higher stress hormone and lower testosterone levels than the second highest ranked or beta males below them--even in times of stability. Surprisingly, alpha male stress levels are similar to those found in low-ranked males. The authors surmise that the cause of stress for these two male classes are probably different: alpha male stress likely comes from having to continually preserve their status and engage high levels of mating activity, while males in the lowest rank of society experience stress related to access to food and other resources. The results suggest that the top position in animal (and possibly human) societies may have unique costs and benefits to be further explored.
