HOLOCENE PALEOENVIRONMENTS OF YEMEN RECONSTRUCTED FROM FOSSIL HYRAX MIDDENS

The paleoenvironmental history of a remote desert area in the Hadamawt region of southern Yemen was reconstructed using plant macrofossils, pollen, and stable isotopes contained within hyrax middens. These fossil deposits, left in caves by the rock hyrax (Procavia capensis) are similar to packrat middens found in western North America. Eleven hyrax middens radiocarbon dated thus far range between 415 and 5239 yr B.P., making this the oldest hyrax midden series yet found. Each deposit contains abundant plant macrofossils and pollen, with an assortment of insects, bones, and snails. One midden, dated to 2159 yr B.P., contains linen cloth, hand-carved amber beads, and a human finger bone suggesting that a human burial took place within the cave. The most abundant shrubs at this site in the Wadi Sana now are: Ziziphus leucodermis, Acacia hamulosa, and A. ehrenbergiana. While the first two have been present since 5239, the third was not found until 2159 yr B.P. This late Holocene appearance of Acacia ehrenbergiana, widespread throughout Yemen today, indicates a return to moister climates following an extremely arid late-middle Holocene. When considered with other geophysical and archaeological results from this site of a moist early-to-middle Holocene, these midden deposits suggest that the period of maximum Holocene aridity in southern Arabian highlands may have been between 5000 and 2500 yr B.P., during which time archaeological evidence also suggests that people abandoned the area. Rock hyrax is not found at this locality today, and the landscape is barren, probably due to recent browsing by goats and camels.