Shape-based identification of caprine taxa using fragmentary skull regions

Fragmentary skull remains are common in zooarchaeological assemblages, yet they pose significant challenges for taxonomic identification because complete skulls are rare. This study investigated whether three resilient cranial regions: the body of the maxilla, the exoccipital region, and the bony palate, retain sufficient shape information to discriminate among caprine taxa. The sample comprised domestic sheep (Ovis aries), wild Marco Polo sheep (Ovis ammonpolii), domestic goat (Capra hircus), and Tatra chamois (Rupicapra tatrica). Three-dimensional landmarks were digitized on surface-scanned skulls. All three regions exhibited significant inter-group shape differences (p: 0.0001). The body of the maxilla provided the strongest discrimination (R² = 0.520), clearly separating ovine from caprine taxa along an axis linked to the relative position of the caudodorsal facial-orbital region versus the infraorbital and alveolar sectors. The exoccipital region showed intermediate discriminatory power, whereas the bony palate exhibited the weakest group structure and the greatest overlap. Centroid size differed significantly among groups (wild sheep being the largest), but shape differences remained significant after accounting for size. Isolated skull fragments, particularly the maxillary body, retain reliable diagnostic shape information for distinguishing caprine taxa. When analyzed using geometric morphometrics, these fragments can serve as valuable analytical units in zooarchaeological studies, even in highly fragmented assemblages.