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(Clark et al.,
1973
) and Jebel 'Uweinat to the well-watered savanna woodlands further
south, with their ferociously biting
Tabanidae
flies (Wickens, 1982), to say nothing
of Trypanosomiasis, Sleeping Sickness and Yellow Fever. However, there seems little
doubt that the late Holocene in Ethiopia (Gasse,
1975
; Williams et al.,
1977
)andthe
Sahara was a time when increasing burning and clearing of land for cultivation in the
wetter areas and grazing by domesticated herds of cattle, sheep and goats in the drier
areas would have accentuated the biological pressures exerted by climatic desiccation
on a flora and fauna adapted to the moister climates of the early Holocene, a topic to
which we return in later chapters.
5.3 The deserts of peninsular Arabia and the Levant
Crossing the Rub' al Khali Desert or Empty Quarter of peninsular Arabia was some-
thing generally best avoided, according to the Bedu camel herders who accompanied
Bertram Thomas (1931), St. John Philby (1932) and especially Wilfred Thesiger
(1946-1950) on their travels in that region. Despite the difficulties, Thesiger in partic-
ular brought back some useful survey data and left a vivid account of his experiences
(Thesiger,
1959
). With the discovery of oil, geological exploration proceeded apace,
providing an impetus for detailed studies of dunes (McKee,
1979
), desert sediments
(Glennie,
1970
) and Quaternary landforms indicative of past climatic fluctuations
(Al-Sayari and Zotl,
1978
). Earlier work had concentrated more on the evidence
for a prehistoric human presence in this now waterless region and on excavating the
long-abandoned cities in former Mesopotamia, including Uruk in the lower Euphrates
Valley, whence came the clay tablets on which was inscribed the
Epic of Gilgamesh
(Sandars,
1972
; see
Chapter 12
).
Three of the world's great monotheistic religions arose in the drylands east of the
Mediterranean - a region that has attracted the interest of pilgrims, biblical scholars
and scientific explorers ever since. The 2,000-year-old Nabatean city of Petra enticed
archaeologists to the area north of Wadi Rum in the Jordanian desert. Occasional
Nabatean grindstones may be seen today near the entrance toWadi Rum, where springs
used to emerge high in the cliffs at the contact between the underlying Precambrian
granites and overlying Palaeozoic sandstones. Further north is Wadi Musa and the
spring where local tradition indicates that Moses struck water from the rock. In the
arid Negev Desert of southern Israel, there are also abundant remains of Nabatean and
later Byzantine settlements, as well as prehistoric remains dating back to the Lower
Palaeolithic (Evenari et al.,
1971
; Horowitz,
1979
; Ginat et al.,
2003
; Goren-Inbar
et al.,
2004
; Avni et al.,
2006
). The evidence of higher lake levels in the Dead Sea Rift
drew the attention of nineteenth-century observers already familiar with accounts of
much expanded lakes in now arid areas, such as central Asia. In his 1865 report on
the geology of the Dead Sea region, Hull was perhaps the first to coin the term
pluvial
to indicate a time when lake basins in now arid areas experienced wetter conditions
