Fig. 1
From: Shape variation and modularity of skull and teeth in domesticated horses and wild equids
Principal component analysis of a the cranial landmark data of 216 adult equid specimens: zebras (n = 47), donkeys (n = 31), Przewalski’s horses (n = 5), and domesticated horses (n = 133), b Shape changes in dorsal and lateral view for PC 1 and PC 2 with black lines presenting positive shape and dotted, grey lines presenting negative shape, c the mandible landmark data of 224 adult equid specimens: zebras (n = 48), donkeys (n = 33), Przewalski’s horses (n = 2), and domesticated horses (n = 141), d Shape changes in dorsal and lateral view for PC 1 and PC 2 with black lines presenting positive shape and dotted, grey lines presenting negative shape, e of the upper 3rd molar landmark data of 225 adult equid specimens: zebras (n = 42), donkeys (n = 25), Przewalski’s horses (n = 3), and domesticated horses (n = 122), f the upper 2rd premolar landmark data of 225 adult equid specimens: zebras (n = 42), donkeys (n = 25), Przewalski’s horses (n = 3), and domesticated horses (n = 122), g of the lower 3rd molar landmark data of 225 adult equid specimens: zebras (n = 29), donkeys (n = 20), Przewalski’s horses (n = 3), and domesticated horses (n = 92), h of the lower 2rd premolar landmark data of 225 adult equid specimens: zebras (n = 29), donkeys (n = 20), Przewalski’s horses (n = 3), and domesticated horses (n = 92); Symbols are circles: domesticated horses, diamonds: Przewalski’s, triangles: zebras, and squares: donkeys