Harris L J
Department of Psychology, Michigan State University, East Lansing 48824.
Psychol Bull. 1993 Sep;114(2):203-34; discussion 235-47. doi: 10.1037/0033-2909.114.2.203.
Cross-sectional life span studies of handedness typically show decreasing percentages of left-handers in older age groups. In an article in Psychological Bulletin, S. Coren and D. F. Halpern (1991) argued that this age trend reflects the shorter life span of left-handers than right-handers. They presented 2 studies of their own providing what they regard to be direct evidence that left-handers, on average, die sooner than right-handers. They also proposed a variety of reasons for what they called left-handers' "decreased survival fitness." I discuss Coren and Halpern's reasons for rejecting a more conventional explanation of the life span data; the 2 studies that they offered in support of their argument; their analysis of other evidence they invoked to account for left-handers' putative decreased survival fitness; and, finally, new studies in which the longevity explanation was tested by more direct means than have been used thus far. I conclude that the case for the "decreased survival fitness" hypothesis cannot be sustained.
关于用手习惯的横断面寿命研究通常表明，在年龄较大的群体中左撇子的比例逐渐下降。在《心理公报》上的一篇文章中，S. 科伦和D. F. 哈尔彭（1991年）认为，这种年龄趋势反映了左撇子的寿命比右撇子短。他们展示了自己的两项研究，提供了他们认为的直接证据，即平均而言，左撇子比右撇子死得更早。他们还为他们所谓的左撇子“生存适应性下降”提出了各种原因。我讨论了科伦和哈尔彭拒绝用更传统的方式解释寿命数据的原因；他们为支持自己的论点而提供的两项研究；他们对为解释左撇子假定的生存适应性下降而援引的其他证据的分析；最后，讨论了通过比迄今为止使用的方法更直接的方式对寿命解释进行检验的新研究。我的结论是，“生存适应性下降”假说的论据站不住脚。
