Fig. 4

Shape differences of the mandible among the three feeding types (omnivory, phytophagy and coprophagy) based on Principal Component Analysis. The 90 % equal frequency ellipses containing approximately 90 % of the data points are shown. The thin-plate splines show the average shape of the mandible for each feeding type, corresponding to the deformation of the landmarks compared with the origin (the average mandibular shape of all species)