Epidermal cell proliferation in the bottlenose dolphin (Tursiops truncatus)

Epidermal cell proliferation in four bottlenose dolphins, Tursiops truncatus, was studied using radioactively labelled thymidine. The epidermal proliferation index (PI) of 7.4 ± 0.6% is 1.3 to 1.9 times higher than that reported for terrestrial mammals. The size of the proliferative pool, a function of the ratio of basal to surface area of the epidermis, was found to be 13.1:1. These two factors combine to give a large proliferative capacity, which contributes to the unusual thickness of the epidermis of Tursiops.