A new field method, now termed the “FM technique”, for age estimation in wild African elephants was outlined in a previous paper (Sikes, 1966a). In this technique, the stage reached in the molar progression which occurs throughout the life of any elephant, is related to a fixed point, namely the foramen mentale, in the lower jaw. The stage reached in any individual elephant of either sex may thus be described as its “molar age” by the “FM formula” (a descriptive, non-mathematical formula). Up to the age of 30 years, molar age may be converted with reasonable accuracy to year age. Above this point, however, any such conversion must be regarded as arbitrary and of doubtful value until such time as adequate additional data from older African elephants of known age become available.
The molars are briefly described, and the molar progression in the species outlined. A hypothesis is offered as a possible explanation of the mechanism of the progression. The field procedure for using the FM technique is explained, and its advantage over previous methods discussed. A comprehensive Age Reference Chart for field use is given, covering the whole potential life span of the African elephant.