Gone fishing...

Fishing is an ancient practice in Africa, dating back 100,000 years, when modern humans started moving into coastal environments. The remains of thousands of fish bones and shellfish from sites on the southern African coastline dating to the Middle Stone Age testify to its antiquity. At the same time that human populations in Africa were developing more sophisticated terrestrial hunting technologies, they were also acquiring innovative and productive fishing and riverine hunting skills. Concomitantly, marine shells were being collected to thread on to twine, probably for use as items of personal ornamentation. Archaeological research has shown that aquatic environments have been exploited for both subsistence and cultural purposes for tens of thousands of years.

We rarely consider the Sahara as the optimum environment for fishing. Seeing painted and engraved images of fish located in these waterless and unfavourable landscapes therefore seems at odds with our present-day knowledge of this vast desert. However, as we have noted before in these project pages (see introductions to Libya and Algeria), water-dependent animals such as crocodile and hippo have regularly been depicted in Saharan rock art, illustrating a once wetter and more fertile landscape. To date, the African rock art image project has catalogued representations of aquatic species in Libya, Algeria and Morocco, depicted with varying degrees of proficiency and ease of identification. This has been an insightful encounter, because it not only informs our thinking about the nature of the environment in the past and the way people were using their available resources, but also allows us to think about the cultural importance of water-based species.

The rock art in these places is a glimpse into an aquatic past that is now supported by environmental evidence. In a recent collaborative project mapping ancient watercourses in the Sahara, it has been shown that during the Holocene (a period which started around 11,700 years ago), this now arid landscape was once covered by a dense interconnected river system, as well as large bodies of water known as ‘megalakes’. When these lakes overflowed, they linked catchment areas, resulting in a dense palaeoriver network that allowed water-dependent life (fish, molluscs and amphibians) to migrate and disperse across an extensive landscape. This interlinked waterway of the Sahara formed a single and vast biogeographic area. Perhaps not surprisingly, rock art sites appear to be clustered around inland deltas where resources would have been most plentiful.

Across the Sahara, at least twenty-three species of fish have been identified in archaeological deposits from the Holocene, the most common being Tilapia, Catfish, African jewelfish, Silver fish and Nile perch. But can we go as far as to correlate the archaeological record with the rock art to species level?

Rock art imagery is replete with both very naturalistic representations and also those which are more conceptual or abstract in nature, and the depictions of fish are no exception. While some representations are clearly identifiable as fish, other are more difficult to identify. For example, the image above from Afforzighiar shows vertical red dots on the left of the photograph are arranged in a fish-like shape that converges at the top and bottom. Additionally it has been deliberately placed on a section of the rock face where there is water seepage, blending the art with the natural environment. The dotted pattern is reminiscent of the African jewelfish (Hemichromis bimaculatus) or even the Redbelly Tilapia (Tilapia zillii), both shown to be species of fish found throughout much of the Sahara during the Holocene.

Some of the engravings bear close morphological resemblances to Catfish, with even the barbels depicted. Catfish seem to occur more regularly in rock art than other species of fish, possibly due to their physical characteristics. They possess an auxiliary breathing organ which allows them to inhabit extremely de-oxygenated water; in fact, when necessary they can obtain up to 50% of their total oxygen requirements from the air. In some cases they will leave the water and crawl on dry ground to escape drying pools. This capacity to live in very shallow waters and to occupy the liminal spaces between land and water has elevated them to more than a simple food source and given them a place of cultural significance in many African societies.

In arid ecosystems, bodies of water are characterised by daily and seasonal fluctuations in water temperature, evaporation and other natural phenomena, and some fish species have adapted well to cope with these extreme changes in water chemistry. Catfish and Tilapia in particular are able to survive high salinity, which occurs through evaporation, while Redbelly Tilapia can also tolerate temperatures above 35° C. Both Sharptooth Catfish and Tilapia are floodplain dwellers and possess the ability to live and spawn in shallow waters, making them easily susceptible to predation. Catfish spines were also used to decorate Saharan pottery with dotted wavy-line patterns. These biological characteristics, which meant they could be easily hunted, may explain their frequent depiction in rock art. Perhaps their value was also reinforced by their being (possibly) the last fish species to survive once aridification had taken hold in the Sahara.

Fish are likely to have been caught in a variety of ways, but in the Sahara the most common technique was to use barbed bone point and/or fish hook technology, with the former being the most archaeologically visible. Barbed points may either be fixed – that is permanently attached to a spear or arrow shaft – or used as ‘harpoons’, when they separate from a shaft on impact and remain attached by a line. Barbed points can actually be used to catch multiple types of prey, but the primary use across Africa was for fish.

Chronologically, the earliest barbed bone point records are from Katanda in the Upper Semliki Valley in modern-day Democratic Republic of the Congo, dating to 80,000 – 90,000 years ago. Here people were catching Catfish weighing up to 68 kg (150 lb), sufficient to feed eighty people for two days. Research has noted the distribution of barbed bone points across the Sahara, and the correlation between these locations and the distribution of species requiring deep water. It is clear that there is continuity in sophisticated fishing technology and practice that has lasted tens of thousands of years.

Other aquatic species are more difficult to identify and are much rarer. For example, the image below has been interpreted as a jelly-fish like creature. However, by manipulating the colour and lighting, the image is a little clearer and appears to share morphological characteristics, such as the rounded carapace and small flippers, with a turtle rather than a jellyfish. Furthermore, we know that softshell turtles (Trionyx triunguis) have been found in archaeological deposits in the Sahara dating to the Holocene. The vertical and wavy strands hanging down underneath could represent the pattern made in the sand by turtles when walking rather than being the tendrils of a jellyfish. In addition, the image from Wadi Tafak below appears to resemble a snail, and is consistent with what we know about the Capsian culture who inhabited modern Tunisia, Algeria, and parts of Libya during the early Holocene (10000–6000 BC). Their distinguishing culinary feature was a fondness for escargots – edible land snails.

A recently excavated cemetery site called Gobero (Sereno et al. 2008), situated on the western edge of the Ténéré desert in Niger, provides a uniquely preserved record of human occupation in the Sahara during the Holocene and puts into context some of the examples of rock art we have looked at here. Pollen analysis has indicated that during the Holocene, Gobero was situated in an open savannah landscape of grasses and sedges, with fig trees and tamarisk, where permanent water and marshy habitats were present.

Approximately 200 burials, ranging over a 5000-year period, were found on the edge of an ancient lake. Grave goods include bones or tusks from wild fauna, ceramics, lithic projectile points, and bone, ivory and shell ornaments. One adult male was buried in a recumbent pose seated on the carapace of a mud turtle. Microliths, bone harpoon points and hooks, and ceramics with dotted wavy-line and zigzag impressed motifs were found in the burial fill, in an associated midden area, and in nearby paleolake deposits. Nile perch (Lates niloticus), large catfish, and tilapia dominate the midden fauna, which also includes bones and teeth from hippos, several bovids, small carnivores, softshell turtles and crocodiles.

The early Holocene occupants at Gobero (7700–6300 BC.) were largely sedentary hunter-fisher-gatherers with lakeside funerary sites. Across the ‘green’ Sahara, Catfish, Tilapia and turtles played important roles socially, economically and culturally. We can see this most explicitly in the burial within a turtle carapace in Gobero, but the representation of aquatic animals in rock art is a significant testament to their value.