Differences in the 2nd to 4th digit length ratio in humans reflect shifts along the common allometric line
2009
Abstract
The use of ratios has been abandoned in most comparative studies. However, ratios are still widely used in evolutionary biology and medicine.
The ratio of the 2nd to the 4th finger (2D:4D), has been the subject of much recent interest in both humans and animals. Most studies agree that 2D:4D is sexually dimorphic.
Nevertheless, here we demonstrate that the sexes do not greatly differ in the scaling between the 2nd and 4th digit. Sexual differences in 2D:4D are mainly caused by the shift along the common allometric line with non-zero intercept.