ASYMMETRIC VAULT MODIFICATION IN HOPI-CRANIA

Cradleboarding was practiced by numerous prehistoric and historic popu lations, including the Hopi. In this group, one result of cradleboardi ng was bilateral or asymmetric flattening of the posterior occipital. We test whether cradleboarding had significant effects on the morpholo gy of the cranial vault, cranial base, and face. Additionally, we exam ine associations between direction of flattening and asymmetric cranio facial growth. A skeletal sample of Hopi from the Old Walpi site inclu des both nonmodified (N = 43) and modified individuals (N = 39). Three -dimensional coordinates of 53 landmarks were obtained using a diagrap h. Thirty-six landmarks were used to define nine finite elements in th e cranial vault, cranial base, and face. Finite element scaling was us ed to compare average nonmodified individuals, with averages of bilate rally, right, and left modified individuals. The significance of varia tion among ''treatment'' groups was evaluated using a bootstrap test. Pearson product-moment correlations test the association of asymmetry with direction of modification. Hopi cradleboarding has a significant effect on growth of the cranial vault, but does not affect morphology of the cranial base or face. Bilateral flattening of the cranial vault leads to decreased length and increased width of the cranial vault. F lattening of the right or left cranial vault results in ipsilaterally decreased length and width coupled with a corresponding increased leng th and width on the contralateral side of the cranial vault. There is a significant correlation of size asymmetry with direction of modifica tion in the cranial vault, but not with size or shape change in the cr anial base or face. (C) 1995 Wiley-Liss, Inc.