Alport Laura J
Department of Anthropology, University of Texas, Austin, Texas 78212, USA.
Anat Rec A Discov Mol Cell Evol Biol. 2004 Nov;281(1):1182-9. doi: 10.1002/ar.a.20123.
In strepsirrhine primates, the accessory olfactory system plays an important role in intrasexual competition. However, it does not play the same role in most haplorhines. In these primates, the main olfactory system and neocortex may have evolved to serve similar functions as the accessory olfactory system in strepsirrhines. To test these hypotheses, the relative size of the main olfactory bulb and neocortex were analyzed for associations with male and female competition frequency and intensity (categorized as low or high). Because neocortex size and competition intensity are associated with diet, only frugivorous species were analyzed (catarrhines, n = 7; platyrrhines, n = 8). Neither the size of the main olfactory bulb nor the neocortex was significantly associated with intrasexual competition among males. However, neocortex size was related to the frequency of female competition. Because the main olfactory system and neocortex both serve multiple purposes, there may not be a single behavioral variable that has selected for their size. Furthermore, categorization of male and female competition intensity reflects physically aggressive behavior. Use of the neocortex for social manipulation may allow males to obtain copulations and females to obtain food resources despite poor physical fighting abilities and low dominance rank.
在狐猴型灵长类动物中，辅助嗅觉系统在同性竞争中发挥着重要作用。然而，在大多数类人猿中它并不起同样的作用。在这些灵长类动物中，主要嗅觉系统和新皮层可能已经进化到具有与狐猴型灵长类动物的辅助嗅觉系统相似的功能。为了验证这些假设，分析了主要嗅球和新皮层的相对大小与雄性和雌性竞争频率及强度（分为低或高）之间的关联。由于新皮层大小和竞争强度与饮食有关，因此仅分析了食果性物种（狭鼻猿，n = 7；阔鼻猿，n = 8）。主要嗅球的大小和新皮层的大小均与雄性之间的同性竞争无显著关联。然而，新皮层大小与雌性竞争频率有关。由于主要嗅觉系统和新皮层都有多种功能，可能不存在单一的行为变量来决定它们的大小。此外，对雄性和雌性竞争强度的分类反映了身体上的攻击行为。尽管身体战斗能力差且优势等级低，但利用新皮层进行社交操纵可能使雄性获得交配机会，使雌性获得食物资源。
