Table 1.

Distributions of younger and older adults for Late Pleistocene samples

			P value
Sample	Younger adults	Older adults (%)	Vs. archeological mean	Vs. ethnographic mean
Late Archaic*	45	14 (23.7)	0.0049	<0.0001
MPMH†	12	1 (7.7)	0.0128	<0.0001
Upper Paleolithic‡	36	13 (26.5)	0.0219	<0.0001

Late Pleistocene samples are shown in Table S1. Binomial P values are for comparisons with the average of the percentage of older adults in the Holocene archeological (39.3%) and ethnographic (65.0%) demographic samples (Table S2).

*Eurasian late archaic humans.

^†Late Pleistocene Middle Paleolithic modern humans from northeastern Africa and southern Asia.

^‡Earlier upper Paleolithic modern humans from approximately 45 to 25 kyr B.P., normally included in Early and Mid Upper Paleolthic human samples (cf. ref. 3).