日本一项研究表明，猴子具有与人一样的面部识别能力，能根据眼和嘴等特征来识别同伴，一旦这些特征发生变化，它们立即能发现其中的不同，但把同伴的面部照片倒立，它们就感觉不到异样。
猴子和人的这个共同特性，在生物学上被称为“撒切尔效应”，这是根据英国前首相撒切尔夫人命名的，因为撒切尔夫人面部的这一特征比较典型。猴子也是人类以外第一个被发现具有“撒切尔效应”的灵长类动物。
日本京都大学灵长类研究所足立几磨等人以恒河猴为研究对象，他们让4只雄性恒河猴观察某些猴子的面部照片，连续观察10次后，它们便逐渐丧失兴趣，最后只花3秒钟左右简单瞄一眼照片。
研究人员接着把照片颠倒，又把照片中的眼睛和嘴颠倒，做出一些新照片让恒河猴观看，结果恒河猴没有表现出兴趣，就好像什么变化都没发生似的；但如果不把照片颠倒，只把照片中的眼睛和嘴颠倒，恒河猴就会对照片再次产生兴趣，它们盯着照片看的时间约有6秒。研究人员认为，注视时间延长表明恒河猴发现了照片中的变化。
研究人员在美国《当代生物学》（Current Biology）杂志上说，这是人们首次发现人类以外的灵长类动物具有“撒切尔效应”，3000万年前人和恒河猴的共同祖先可能就具有了这种能力。（生物谷Bioon.com）
生物谷推荐原始出处：
Current Biology, 25 June 2009 doi:10.1016/j.cub.2009.05.067
Thatcher Effect in Monkeys Demonstrates Conservation of Face Perception across Primates
Ikuma Adachi1,3,Dina P. Chou2andRobert R. Hampton1,2,,
1 Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
2 Department of Psychology, Emory University, Atlanta, GA 30322, USA
3 Present address: Kyoto University Primate Research Institute, Kyoto University, Kanrin, Inuyama City, Aichi, 484-8506, Japan
Accurate recognition of individuals is a foundation of social cognition. The remarkable ability of humans to distinguish among thousands of similar faces depends on sensitivity to unique configurations of facial features, including subtle differences in the relative placement of the eyes and mouth [1,2]. Determining whether similar perceptual processes underlie individual recognition in nonhuman primates is important for both the study of cognitive evolution and the appropriate use of primate models in social cognition research. In humans, some of the best evidence for a keen sensitivity to the configuration of features in faces comes from the Thatcher effect. This effect shows that it is difficult to detect changes in the orientation of the eyes and mouth in an image of an inverted face, even though identical changes are unmistakable in an upright face [3,4]. Here, we demonstrate for the first time that a nonhuman primate species also exhibits the Thatcher effect. This direct evidence of configural face perception in monkeys, collected under testing conditions that closely parallel those used with humans, indicates that perceptual mechanisms for individual recognition have been conserved through primate cognitive evolution.
