Finger ridge patterns and tactile sensitivity.

Tactile sensitivity has been measured in 101 normal individuals (38 females and 63 males) of European origin, and compared with ridge pattern characteristics of the fourth fingertip of the right hand. There is a relationship of tactile sensitivity performance with the type of pattern, particularly in females, and also with the number of junctions within the pattern, particularly in males. The possible origin of sex differences in tactile sensitivity and in its relationships with dermatoglyphic variables is discussed. In spite of sex differences, optimal tactile sensitivity performance seems to be associated with medium-sized loop patterns which have a greater number of junctions than ends and also have grooves wider than ridges. The possible evolutionary significance of these associations is discussed in relation to evidence for epistatic genetic variation for pattern intensity.