UNESCO Ancient Civilizations of Africa (Editor G. Mokhtar)

West Africa before the seventh century
from these levels are also described by the investigator as 'fitting well with
historic and modern Dyola practices', while the sequence of pottery types
links the ancient and the nearby modern middens.
On our present view, this sequence seems too recent to shed much light
on the origins of wet rice agriculture in the area. It may be useful, however
to note here that according to Portères, 63 Senegambia was a secondary
centre of Oryza glaberrima propagation, the primary centre being somewhere
near the middle Niger.
The lower Casamance sites appear to represent an advanced stage of
wet rice cultivation. At this time the use of iron tools makes it possible
to reclaim mangrove swamps and ridge heavy alluvial clay soils for paddy
fields. We may in fact do well to look for the first centres of Oryza glaberrima
cultivation in the looser soils of drained inland valleys where it would have
been possible to cultivate dry land or mountain rice by broadcasting or
punch-hole planting after clearing by girdling the trees with stone
implements.
What actually happened can only be discovered, if at all, by means of
more full-scale archaeological investigations of key areas. In any case it
is now known that recognizable aspects of Dyola culture were already
present from Period II onwards. Groups lived on sandy ridges in or near
alluvial valleys, just as they do today, depositing their rubbish in particular
spots. There it accumulated in regular middens, which contain pottery
fragments and other refuse comparable with Dyola material culture.
Throughout the sequence the ceramic tradition of lower Casamance
emphasized incised, punctuated and impressed rather than painted
decorations and utilitarian rather than ornamental or ceremonial shapes.
Whether or not these Casamance people buried pots with their dead remains
unknown, since no graves were found in or near the sites.
It has been suggested by scholars such as Arkell that the West African
iron working traditions described above were derived from Egypt or Nubia,
whilst others, such as Mauny, favour Carthage. But the proponents of
such views fail to appreciate, among other things, the fundamental
difference in the way iron metallurgy developed in the two areas. In Egypt
and Nubia the transition to the iron age was achieved through the working
of copper, gold, silver and meteoric iron in the predynastic period, and
then of terrestrial iron. In contrast, the centres of ancient iron working
in Africa south of the Sahara appear to have progressed straight from stone
to iron, with little or no copper or bronze except perhaps in Mauretania.
In fact copper and bronze were later worked in much the same way as
iron, whereas in Egypt and Nubia copper and iron were worked by very
different methods. Available dating evidence gives no more support to
either variant of the diffusion theory of iron working than does directly
retrieved cultural evidence. It appears, for instance, that the Garamantes
63. A. Portères, 1950.
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