Morphometric affinities of the human shoulder



A recent discussion by Corruccini and Ciochon ('76) implies that previous multivariate morphometric studies of the shoulder, reviewed in Oxnard ('73), have been misinterpreted because due allowance was not made for the overall sizes of the specimens. Results that were given functional significance in the earlier investigations are cited as being due at least in part to overall bodily size. Although examination of the range of genera selected for mention by Corruccini and Ciochon seems superficially to support this view, it is demonstrated here that examination of the full range of genera in the earlier studies refutes, unequivocally, that suggestion.

The discussion by Corruccini and Ciochon ('76) also implies that the more complex size correction applied in their study produces a result different from that of the previous workers. Again, although perusal of the particular part of the earlier study selected for discussion by Corruccini and Ciochon would appear to bear that out, it is demonstrated here that comparisons with all parts of the earlier results provide a different picture. Thus the main result of Corruccini and Ciochon replicates rather closely a more restricted part of the earlier result not mentioned by Corruccini and Ciochon. The difference between Corruccini and Ciochon's principal result and the main result of the prior authors is shown to rest upon the difference between the more restricted earlier study of “residual” shoulder dimensions and the other broader studies; i.e., not upon any multivariate manipulation, but upon the inclusion in the broader study of a wider range of information about the shape of the primate shoulder.

Knowledge of these and other points is important in assessing the overall contribution of the discussion of Corruccini and Ciochon.