It is widely accepted that African pastoralism with cattle, sheep and goats emerged long before plant domestication2, in contrast to the process of ‘neolithization’ in the Near East, characterized by the transition from a mobile hunter-gatherer lifestyle to an increasingly settled, agricultural way of life. In Saharan Africa, during the Early Holocene, largely sedentary and pottery-producing hunters, fishers and gatherers became nomadic cattle herders3, dynamically adapting to, and exploiting, different environments and resources.

Today, it seems impossible that cattle could survive in such a hostile environment as the arid desert land of the Sahara, but this region enjoyed vastly more favourable climatic and environmental conditions12 during the Holocene African Humid Period, which began around 10,000 years ago13. Here, faunal evidence demonstrates that by the early sixth millennium bc, cattle, sheep and goats were found together across the savannas of what is now the Sahara1,5. This suggests that the inception of dairying practices in North Africa and an early and independent ‘secondary products’ economy14 seems plausible given what we now know of the first appearance of milking in the Near East8.

Compelling evidence of prehistoric cattle herding in northern Africa comes from the remarkable rock paintings and engravings of the Sahara (Fig. 1), possibly the world’s largest concentration of prehistoric art, long known for their rich and vivid portrayal of scenes from everyday life4,15,16. The extensive rock art demonstrates that cattle played an important part in the lives and ideology of ancient human groups living in this region during the Holocene. This pictorial record contains countless scenes with representations of cattle, some emphasizing the female’s full udders and, in a few cases, depictions of the actual milking of a cow, such as at Wadi Teshuinat II15 in the Acacus or Wadi Tiksatin in the Messak16. However, reliable dates for this rock art can rarely be ascertained4.

Figure 1: Rock art image and tracing from Teshuinat II rock shelter, South West Libya. a, b, Rock art image (a) and tracing (b) showing Saharan pastoralists with their pots and cattle (adapted with permission from ref. 15). PowerPoint slide Full size image

Faunal remains from securely dated contexts indicate that domesticated animals (cattle, sheep or goats) were present in the area from the early sixth millennium bc, becoming much more common in the fifth millennium bc. Unfortunately, these remains are highly fragmented and poorly preserved, precluding herd reconstructions, and thus even indirect evidence of dairying is missing5.

Direct evidence for the practice of dairying, beginning in the seventh millennium bc in northwestern Anatolia8, appearing in the sixth millennium bc in eastern Europe11 and reaching Britain in the fourth millennium bc9,10, has been established through the compound-specific stable carbon isotope analysis of animal fat residues preserved in archaeological pottery. Notably, this research on the antiquity of dairying practices has largely been confined to Europe, the Near East and Eurasia, with no attempt yet being made to identify the inception of dairying practices in the African continent.

Here we present direct chemical evidence for early dairying practices within the central Sahara through the use of gas chromatography (GC), gas chromatography–mass spectrometry (GC–MS) and gas chromatography–combustion–isotope ratio mass spectrometry (GC–C–IRMS) analyses carried out on organic residues extracted from archaeological pottery sampled from the Takarkori rock shelter located in the southwest Fezzan, Libyan Sahara, an area licensed to Sapienza University of Rome (Supplementary Fig. 1). Four seasons of fieldwork identified evidence of Late Acacus (hunter-gatherer) occupation followed by Early, Middle and Late Pastoral remains (Supplementary Fig. 2), dating between approximately 8100 and 2600 bc (Supplementary Table 1). This long Pastoral period, between approximately 6000 and 2600 bc, denotes the adoption of cattle together with sheep and goats, combined with intensive exploitation of wild cereals17,18.

Analyses of absorbed organic residues focused on 81 potsherds (Supplementary Table 2), covering a wide range of decorative techniques and motifs found on Saharan ceramics18,19 (Supplementary Fig. 3). These vessels were mainly excavated from securely dated Middle Pastoral (n = 56) levels (approximately 5200–3800 bc), with a small number originating from the Late Acacus (n = 8) and Early (n = 14) and Late Pastoral (n = 3) periods. The lipids were extracted using established protocols8,9,10. Many potsherds demonstrated extraordinary preservation of lipids, containing concentrations of up to 6 mg g−1 (mean 1.2 mg g−1), with one particular potsherd (TAK 443) having a concentration of 17 mg g−1. It is noteworthy that lipids were observed in every potsherd, in contrast to European archaeological sites, where generally <40% of potsherds contain extractable lipids with mean concentrations of approximately 0.1 mg g−1 (refs 10, 20). This remarkable preservation is likely to be related to the extremely arid conditions prevailing in the region.

Lipid biomarker analyses by GC–MS showed that residues fall into three broad categories (Fig. 2). The most common distribution (Fig. 2a) was dominated by high abundances of the C 16:0 and C 18:0 fatty acids, which derive from degraded animal fats. Also abundant were branched-chain fatty acids, C 13 to C 18 , components of bacterial origin diagnostic of ruminant animal fats21. The second most common type of residue (Fig. 2c) contained a relatively low abundance of the C 18:0 alkanoic acid, with several extracts showing high abundances of C 12 and C 14 homologues. Such distributions have rarely been seen in European pottery and are more diagnostic of plant oils22. Also present, and again rarely seen in European prehistoric ceramics, are a homologous series of long-chain n-alkanes from C 16 –C 33 (odd-over-even carbon number predominance), usually maximising at C 25 , regarded as originating from epicuticular waxes of vascular plants23. A third, intermediate category of residue (Fig. 2b) is characterized by a series of α,ω-dicarboxylic acids (diacids), in the C 5 to C 18 carbon-chain-length range (Fig. 2a, b) with C 9 (azelaic acid) the most abundant homologue, the latter commonly deriving from the ‘drying reaction’ of plant oils24. Such residues also contained long-chain alkyl lipids of plant origin. Together such mixtures probably reflect either processing of both plant and animal products in the vessels or the multi-use of vessels.

Figure 2: Partial gas chromatograms displaying the trimethylsilylated lipid extract from potsherds excavated from Middle Pastoral levels in the Takarkori rock shelter. a–c, The distributions are characteristic of degraded animal fat (a), a mixture of animal and plant fats (b) and plant material (c). Chromatographic peak identities denoted by filled triangles comprise straight-chain fatty acids in the carbon chain range C 9:0 to C 29:0 , maximizing at C 16:0 ; filled squares represent n-alkanes in the carbon-chain range C 20:0 to C 35:0 ; and filled circles indicate α,ω-dicarboxylic acids (diacids) in the carbon-chain range C 5:0 to C 16:0 . IS, internal standard, C 34 n-tetratriacontane. PowerPoint slide Full size image

Of the 81 potsherds, only those residues unambiguously assigned as degraded animal fats (Table 1)—that is, those dominated by palmitic (C 16:0 ) and stearic (C 18:0 ) alkanoic acids (for example, Fig. 2a)—were selected for GC–C–IRMS analysis to determine the δ13C values for C 16:0 and C 18:0 , with the aim of establishing their origins. Differences in the δ13C values of C 16:0 and C 18:0 alkanoic acids are due to the differential routing of dietary carbon and fatty acids during the synthesis of adipose and dairy fats in ruminant animals, thus allowing ruminant milk fatty acids to be distinguished from carcass fats by calculating Δ13C values (δ13C 18:0 –δ13C 16:0 ) and plotting that against the δ13C value of the C 16:0 alkanoic acid. Previous research has shown that by plotting Δ13C values, variations in C 3 versus C 4 plant consumption are removed, thereby emphasizing biosynthetic and metabolic characteristics of the fat source9,10. We have now confirmed this through the GC–C–IRMS of a new reference collection of modern ruminant animal fats from Africa collected to encompass the range of carbon isoscapes25 likely to have been encountered by early Saharan pastoralists. The δ13C values of the C 16:0 and C 18:0 components of these modern fats, presented in Fig. 3, show δ13C values of goat dairy fats from the Acacus region, Libya (n = 9), together with cattle dairy fats and cattle, sheep and goat adipose fats (n = 9, 12, 7 and 12, respectively) from Kenya. The δ13C 16.0 values for the C 16:0 alkanoic acids of the African reference fats plot in the range from −35 to −15‰, indicating diets ranging from predominantly C 3 to C 4 . These results confirm the global applicability of the Δ13C proxy.

Table 1 Subset of potsherds selected for isotopic analyses Full size table

Figure 3: Plots of δ 13 C values and Δ 13 C values of alkanoic acids in modern reference ruminant fats and archaeological animal fat residues in prehistoric Saharan pottery. a–c, Plots of the δ13C 16:0 and δ13C 18:0 values for archaeological animal fat residues in Late Acacus (hunter-gatherer) and Early Pastoral (Neolithic) pottery (a), archaeological animal fat residues in Middle and Late Pastoral Neolithic pottery (b), and modern reference animal fats collected from Libya and Kenya (c). d–f, Plots denote Δ13C values for the archaeological fat residues (Late Acacus/Early Pastoral) (d) and Middle/Late Pastoral (e) and modern reference animal fats (f). Notably, the residues originating from the Late Acacus and Early Pastoral periods (d) do not contain dairy fats, and plot in the non-ruminant range, probably deriving from wild fauna. e, The extensive processing of dairy products in pottery vessels from this region begins in the Middle Pastoral period approximately 5200–3800 bc. The broad array of values suggests that the animals giving rise to these ruminant fats subsisted on an extensive range of different diets either composed completely of C 3 plants, varying amounts of C 3 and C 4 plants or, for some of the archaeological samples, a diet comprising wholly C 4 plants. The ranges shown here represent the mean ± 1 standard deviation of the Δ13C values for a global database comprising modern reference ruminant animal fats from Africa, the UK (animals raised on a pure C 3 diet)10, Kazakhstan28, Switzerland29 and the Near East30, published elsewhere. PowerPoint slide Full size image

Of the 29 animal fat residues selected for GC–C–IRMS analyses, 22 originate from Middle Pastoral levels, 3 from the Late Acacus, 2 from the Early Pastoral and the remaining 2 from the Late Pastoral period (Table 1). The comparison of the Δ13C values of the modern reference animal fats with those of the archaeological pottery residues from the Middle Pastoral period (approximately 5200–3800 bc) show that 50% of these plot within, or on the edge of, the isotopic ranges for dairy fats, with a further 33% falling within the range for ruminant adipose fats and the remainder corresponding to non-ruminant carcass fats (Fig. 3). Notably, the residues originating from earlier periods do not contain dairy fats, and plot in the non-ruminant fat range, probably deriving from wild fauna found locally. The unambiguous conclusion is that the appearance of dairy fats in pottery correlates with the more abundant presence of cattle bones in the cave deposits, suggesting a full pastoral economy as the cattle were intensively exploited for their secondary products.

Of particular note is the wide range of δ13C values exhibited by the alkanoic acids, plotting across the range −25‰ to −10‰, which is broader even than the reference fats range (maximum −15‰). This suggests that the animals giving rise to these fats had subsisted on an extensive range of different forages either composed completely of C 3 plants, varying combinations of C 3 and C 4 plants, or a diet comprising wholly C 4 plants. The wide range of alkanoic acid δ13C values found for these African potsherds is unprecedented and points to differing pastoral modes of subsistence (such as vertical transhumance, which is still practised today) by these prehistoric Saharan groups. This is supported by their settlement pattern based on summer sites in the lowland sand seas and winter sites (such as Takarkori) in the mountains3, which was probably in response to seasonal weather patterns.

Our findings provide unequivocal evidence for extensive processing of dairy products in pottery vessels in the Libyan Sahara during the Middle Pastoral period (approximately 5200–3800 bc), confirming that milk played an important part in the diet of these prehistoric pastoral people. The findings are notable for three other reasons: (1) they confirm that domesticated cattle, used as part of a dairying economy, were present in North Africa during the fifth millennium bc, thus supporting the idea of an earlier ingression into the central Sahara1,2,3 and suggesting a local process of pastoral development, based on the exploitation of secondary products; (2) the finding of dairy fat residues in pottery is consistent with milk being processed, thereby providing an explanation of how, in spite of lactose intolerance, milk products could be consumed by these people with the practice being adopted quickly; (3) they are consistent with the finding of the −13910*T allele, associated with the lactase persistence trait in Europeans, across some Central African groups such as the Fulbe from northern Cameroon26, supporting arguments for some movement of people, together with their cattle, from the Near East into eastern Africa in the Early to Middle Holocene; and (4) they provide a context for understanding the origins and spread of other, independently arising LP-associated gene variants in sub-Saharan Africa27.