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This paper reports on the first AMS (14)C dating of coatings over wall depressions, or cupules, from an archaeological site in sub-Saharan Africa. Rhino Cave is primarily a Late and Middle Stone Age site located at the Tsodilo Hills in the northwestern Kalahari Desert of Botswana. A secondary precipitate up to 10 cm thick covers many of the 544 cupules engraved into one wall of the cave; this precipitate or coating was removed from two of these depressions. The coatings consisted of calcium phosphate, presumably derived from bat guano or bird droppings above the hollows, that was overlain by calcium carbonate and then silica. Organic material in this precipitate provided minimum calibrated AMS (14)C ages of 6443 to 6204 cal. yr B. P. (5580 +/- 60 (14)C yr B. P.) for one depression, and 3000 to 2761 cal. yr B. P. (2830 +/- 50 (14)C yr B. P.) for the other. The AMS (14)C ages and paleoclimatic data recovered from the cupules are in agreement with the regional paleoclimatic sequence for the Holocene. Specifically, comparison with data from Etosha Pan in Namibia and the Makgadikgadi Pans in Botswana suggests that deposition of the coatings and associated organic matter occurred preferentially during three periods of increased moisture in the region at around 6200, 3700, and 1200 cal. yr B. P. The gradual change from phosphate at the base of the coatings to carbonate and then to silica suggests that the wet intervals were superposed on a long-term trend toward a drier climate in the late Holocene. (C) 2010 Wiley Periodicals, Inc.