Supplementary material from: ZooMS confirms geometric morphometrics species identification of ancient sheep and goat

Geometric morphometrics can effectively distinguish isolated third lower
molars of present-day sheep and goat, but its applicability to
archaeological specimens has yet to be established. Using a modern
reference collection of 743 sheep and goats and a 2D-landmark-based
geometric morphometric (GMM) protocol, this study aimed to
morphometrically identify 109 archaeological specimens, used as case
studies, dating from the Late Neolithic to the modern period/era. These
morphometric identifications were then compared to molecular
identifications via collagen peptide mass fingerprinting, known as
Zooarcheology by Mass Spectrometry (ZooMS). ZooMS confirmed the
morphometric identifications for 104 specimens, with the five
misidentified specimens all morphometrically identified as goat. 
Modern sheep and goats have larger teeth and distinct shapes compared to
their archaeological counterparts, suggesting strong differences between
archaeological and modern specimens potentially linked with recent breed
improvement or geographic origin of the specimens. In addition, for both
species, some of the archaeological dental morphologies do not match with
any of our modern references. This study validates the applicability of
geometric morphometrics for identifying isolated archaeological sheep and
goat teeth. It represents a stepping stone for future, non-destructive,
bioarchaeological studies of the two species.