Figure 1.

Scatterplot of the length of the fingers on right hands in 297 biology students. The common line estimated by the ordinary least-square linear regression is depicted as the solid line (length of the 2nd finger = 0.823 (length of the 4th finger) + 11.223; p < 0.00001; r² = 0.81). Its intercept is significantly larger than zero (b = 11.223 ± 1.654; p < 0.00001), which means the 2D : 4D ratio necessarily decreases with increasing finger length. The sexes do not significantly differ in the scaling relationship between the length of the 2nd and 4th finger (see table 1 for statistics). Women, circles and dotted line; men, squares and broken line.