Development of the tush and tusk and tusklessness in African elephant (Loxodonta africana)

Abstract

The embryologic development of the tush and tusk of the African elephant was studied by means of serial histologic sections prepared from elephant embryos with masses varying between Ig and 240 g. Statistics on tusklessness obtained during a four year population control programme in the Kruger National Park were analysed and compared with those reported in other elephant reserves in Southern Africa. Maxillae of eight elephant embryos, the maternal histories of which were available in six cases, were radiographed, dissected and examined microscopically. This study has shown that the tush and tusk develop from one tooth germ in a deciduous to permanent tooth relationship. Tusklessness was found to be unilateral or bilateral and associated with either the absence or presence of a tush. The possible causes of the differences in the frequency of bilateral tusklessness in different elephant populations are discussed.