社交对动物认知能力的影响是演化生物学中一个热门话题。在灵长类中，有证据支持社会智能假说，即社会环境决定能力的选择，如估计其他个体间社会关系的能力。尽管该话题在生物演化中具有潜在重要性，但这一假说仅在灵长类中做过验证。现在，对斑胸草雀（被研究得最彻底的鸣鸟）所做的一项研究表明，它们也能估计群体中配偶间的社会关系。当一只雄鸟处在未配对的同伴面前时，它对来自自己配偶的叫声和来自其他雌鸟的叫声反应是一样的。在一对配对的雄鸟和雌鸟面前，它对自己的配偶的反应更为强烈。本期封面所示为一只雄斑胸草雀（右上、黄色栖木）、其配偶和一些旁观的鸟。
Audience drives male songbird response to partner's voice
According to the social intelligence hypothesis, social context represents an important force driving the selection of animal cognitive abilities such as the capacity to estimate the nature of the social relationships between other individuals. Despite this importance, the influence of this force has been assessed only in primates and never in other animals showing social interactions. In this way, avian communication generally takes place in a network of signallers and receivers, which represents an audience altering individual signalling behaviours. Indeed, vocal amplitude and repertoire are known to be socially regulated and the attitude towards the opposite sex may change depending on the audience. This 'audience effect' provides support for the reality of social awareness in some bird species. However no evidence has yet been found to suggest that birds are able to estimate the characteristics of the social relationships between group-mates. Here we show that the male of a gregarious songbird species—the zebra finch (Taeniopygia guttata)—pays attention to the mating status of conspecific pairs, and uses this information to control its behaviour towards its female partner.
