Toward a reduction in tooth number: the case of P_1 in roe deer from Slovenia

摘要

The permanent dentition of roe deer (Capreolus capreolus L.) comprises 30-32 teeth with the following dental formula: I 0/3, C 0/(1), P 3/3, M 3/3. Variations in tooth number and shape are rather uncommon in this species and factors determining roe deer dentition are considered to be quite stable. In both upper and lower jaws the first premolar is normally missing, but can be occasionally observed. To discover the frequency of P_1 in the whole population, its occurrence was studied in the left hemi-mandibles of the total one-year (2007) roe deer mortality in Slovenia, representing a large sample set of 41,895 individuals. The first premolar was detected in only 27 individuals (13 males, 12 females, 2 without data), indicating that its occurrence isvery low and sporadic (0.6%). Furthermore, the results of previous archaeozoological and embryological studies were analyzed. On the basis of observed facts, we conclude that the first mandibular premolars of roe deer belong to a category of tooth that has been suppressed in the evolution of the Cervidae.