Table 2.

Mahalanobis' distance test comparing KNM-WT 40000 using all PCs combined. D², squared Mahalanobis' distance of KNM-WT 40000 from centroid of species sample; SDU, standard deviation unit of Mahalanobis' distances within the sample; d.f., degrees of freedom; p, probability that KNM-WT 40000 belongs to the species. For sample sizes less than six, the probability is not calculated (n/a) because estimates of the variance are insufficiently reliable.

	D2	SDU	d.f.	p-value
KNM-WT 40000 (corrected)
A. afarensis	21.065	4.589	6	<0.0025
A. africanus	37.084	6.089	4	n/a
P. robustus	13.284	3.644	6	<0.05
KNM-WT 40000 (as preserved)
A. afarensis	18.909	4.348	6	<0.005
A. africanus	36.609	6.050	4	n/a
P. robustus	13.738	3.706	6	<0.05
KNM-WT 40000 (corrected), adults only
A. afarensis	33.088	5.752	5	n/a
A. africanus	28.397	5.328	3	n/a
P. robustus	20.390	4.515	4	n/a