Landmark-Based Geometric Morphometrics in Describing Facial Shape of the Sama-Banguingui Tribe from the Philippines

Studies of human forms using traditional methods only show minimal variations. However, advances in image analysis and statistics have resulted to highly quantitative descriptions of detailed variations. To be able to describe detailed variations and to understand the human face of tribes practicing consanguineous marriages like the Sama-Banguingui tribe, landmark-based geometric morphometrics was used. Selected purebreed individuals (25 males and 21 females) of the tribe participated in the study. Face images were landmarked using the 28 anatomical landmarks defined in this study. Relative warps scores generated were used for the analysis of shape variations. Visualization of variations was done using histograms and boxplots. Results showed minor differences in the shapes of the whole face in RW2 and RW3 but not in RW1, RW4, RW5 and RW6 where variations observed were not significantly different. The similarity in the facial characters within and between sexes observed in this study could be attributed to common ancestry and possibly due to consanguinity. This study have shown that the tools of geometric morphometrics can be used for detailed quantification of variations in shapes of morphological structures. 