Ambient temperature does not affect the tactile sensitivity of mystacial vibrissae in harbour seals.

Vibrissae provide pinnipeds with tactile information primarily in the aquatic environment, which is characterized by its high thermal conductivity and large potential cooling power. Since studies of thermal effects on human tactile sensitivity have revealed that cooling below normal skin temperature impairs sensitivity, the present study investigates the tactile sensitivity of the vibrissal system of harbour seals at varying ambient temperatures. Using plates bearing gratings of alternating grooves and ridges, the texture difference thresholds of two adult seals were determined under water.