McFadden Dennis, Shubel Erin
Department of Psychology, Institute for Neuroscience, University of Texas, Austin, Texas 78712, USA.
Horm Behav. 2002 Dec;42(4):492-500. doi: 10.1006/hbeh.2002.1833.
Digital scans of the hands and feet were obtained from 62 heterosexual females and 60 heterosexual males. Scans only of the hands were obtained from 29 homosexual females and 35 homosexual males. The lengths of the individual fingers and toes were estimated from those images by two experienced judges, and length ratios were constructed for all possible pairs of fingers (or toes) on each hand (or foot). Thumbs were not measured, but the great toe was measured and used to construct length ratios. Past research had concentrated on the relative lengths of the index and ring fingers (the 2D:4D ratio). This ratio is close to 1.0 in females and smaller than 1.0 in males. Here 2D:4D did exhibit the largest sex difference, for both hands, followed by 2D:5D and 3D:4D. The sex differences were larger for the right hand than for the left. For both homosexual females and homosexual males, nearly all of the length ratios for fingers were intermediate to those for heterosexual females and heterosexual males; that is, the ratios of homosexual females were masculinized and those of homosexual males were hypomasculinized, but few of these differences were significant. Because many toes were substantially arched, acceptable estimates of length often could not be obtained from the two-dimensional scans, meaning that conclusions about toes are much less certain than those for fingers. Nevertheless, the length ratios were generally larger for toes than for fingers, and the sex differences were generally smaller for toes.
对62名异性恋女性和60名异性恋男性的手和脚进行了数字扫描。对29名同性恋女性和35名同性恋男性仅进行了手部扫描。两名经验丰富的评判员根据这些图像估算了各个手指和脚趾的长度，并为每只手（或脚）上所有可能的手指（或脚趾）对构建了长度比。拇指未进行测量，但对大脚趾进行了测量并用于构建长度比。以往的研究集中在食指和无名指的相对长度（2D:4D比率）上。该比率在女性中接近1.0，在男性中小于1.0。在这里，双手的2D:4D确实呈现出最大的性别差异，其次是2D:5D和3D:4D。右手的性别差异比左手更大。对于同性恋女性和同性恋男性而言，几乎所有手指的长度比都介于异性恋女性和异性恋男性之间；也就是说，同性恋女性的比率男性化，而同性恋男性的比率男性化不足，但这些差异很少有统计学意义。由于许多脚趾明显弯曲，二维扫描通常无法获得可接受的长度估算值，这意味着关于脚趾的结论远不如关于手指的结论确定。尽管如此，脚趾的长度比通常大于手指，并且脚趾的性别差异通常较小。
