Finger Millet processing in East Africa

Ethnoarchaeology, 2021

An ethnoarchaeological study was conducted in northwestern Ethiopia on the cultivation of dagusa (Amharic), commonly known as finger millet (Eleusine coracana) in English. Dagusa is one of the most important cereals and staple foods in East and Central Africa. The field study examined crop-processing activities from land preparation to food processing. The study documented traditional agricultural techniques, land races, labor organization, foods, and rituals associated with cultivation of the crop. Experimental charring was conducted to examine the transformation and preservation of different varieties of dagusa including cultivated and wild progenitor varieties within both oxidized and reduced combustion environments. The results show that survivability varies by seed color at temperatures between 250°C and 350°C. All components of the plants show better rates of survivability at these lower temperatures. The combined ethnoarchaeological and experimental study could influence where and how archaeobotanists observe evidence of food production and processing of finger millet.

Ethnoarchaeology, 2022

An ethnoarchaeological study was conducted in northwestern Ethiopia on the cultivation of dagusa (Amharic), commonly known as finger millet (Eleusine coracana) in English. Dagusa is one of the most important cereals and staple foods in East and Central Africa. The field study examined crop-processing activities from land preparation to food processing. The study documented traditional agricultural techniques, land races, labor organization, foods, and rituals associated with cultivation of the crop. Experimental charring was conducted to examine the transformation and preservation of different varieties of dagusa including cultivated and wild progenitor varieties within both oxidized and reduced combustion environments. The results show that survivability varies by seed color at temperatures between 250°C and 350°C. All components of the plants show better rates of survivability at these lower temperatures. The combined ethnoarchaeological and experimental study could influence where and how archaeobotanists observe evidence of food production and processing of finger millet.

Eleusine coracana (finger millet) is a nutritious and easily storable grain that can be grown in unfavourable environments and is important to the food security of millions of farmers in Africa and South Asia. Despite its importance and promise as a sustainable crop for smallholders in the Global South, its history remains poorly understood. Eleusine coracana has only rarely been recovered from archaeological sites in the region of Africa where it was domesticated and never in quantities large enough to study its evolution under cultivation. Here we report on a large assemblage of Iron Age (ca. 900-700 cal bp) E. coracana grains recovered from Kakapel rock shelter in western Kenya. We also carried out carbonization experiments on modern grains in order to directly compare these archaeological specimens to extant landraces. We found that finger millet is only well preserved when carbonized at temperatures lower than 220 °C, which may contribute to its scarcity in the archaeological record. Eleusine coracana shrinks but does not significantly change shape when carbonized. When corrected for the effects of carbonization, the E. coracana grown by Iron Age farmers at Kakapel was smaller grained than modern landraces, but is nonetheless identifiable as domesticated on the basis of grain shape and surface texture. A comparison with other Iron Age E. coracana reveals considerable variation in the grain size of landraces cultivated during this era. This is the largest quantitative morphometric analysis of E. coracana grains ever conducted, and provides a basis for the interpretation of other archaeological populations. This assemblage is also the first evidence for E. coracana cultivation in western Kenya, a biodiversity hotspot for landraces of this crop today.

Azania: Archaeological Research in Africa, 2019

Charred botanical remains and plant impressions in pottery sherds and baked clay pieces recovered during survey and archaeological excavation mainly at Mahal Teglinos (Kassala, K-1), Sudan, were examined for botanical remains. Archaeobotanical analyses were undertaken on these and similar artefacts recovered during surveys of the same site and its surrounds (Kashim el-Girba and Shurab el-Gash). The studied samples yield evidence for plant use and cultivation of millets and the presence of different edible and non-edible plant species. This paper focuses primarily on the varieties of small seeded millets recovered from archaeological contexts. Previous archaeobotanical reports from the region lack detailed reports on the early history and agricultural value of small seeded millets, except for a focus on sorghum and pearl millet. The recovered millet varieties include Paspalum, Setaria, Brachiara, Echinochloa and Pennisetum. The identified taxa were both morphologically wild and cultivated. They date to between the mid-fourth millennium BC (Butana Group) and the mid-first millennium AD (Hagis Group). The results of the study indicate that alongside sorghum were small seeded millets likely used for human consumption and/or animal fodder in settlement contexts dating back to the mid-fourth millennium BC. Unlike previous reports on seed impressions and glumes, this study also relies on analysis of desiccated and charred small seeded millets.

Vegetation History and Archaeobotany, 2022

The Nok culture in central Nigeria, dated 1500-1 cal bc, is known for its famous terracotta sculptures. We here present a study on > 11,000 botanical macro-remains from 50 sites, including 343 samples from Nok contexts and 22 samples dating between cal ad 100 and 400, after the end of the Nok culture. With 9,220 remains, pearl millet (Cenchrus americanus (L.) Morrone, syn. Pennisetum glaucum (L.) R.Br.) is dominant in the Nok samples, followed by cowpea (Vigna unguiculata (L.) Walp.), Canarium schweinfurthii Engl., Nauclea latifolia Sm. (syn. Sarcocephalus latifolius (Sm.) E.A.Bruce), wild fruit trees and wild Poaceae. The pearl millet remains consist exclusively of charred caryopses; chaff remains are completely absent. Because we studied all size fractions, including the small 0.5 mm fractions usually containing the involucres, bristles and husks, the absence of pearl millet chaff is real, excluding a methodological explanation, and distinguishes Nok from contemporary other West African sites. We propose that most excavated Nok sites were consumer sites where clean grain was brought in from outside and consumed in a ritual context connected with feasting. This is in line with the archaeological evidence from the larger excavated sites with stone-pot arrangements that are interpreted as ritual places related to mortuary practices. In addition to the known southward branches of pearl millet diffusion from the Sahara we propose a new, hitherto unknown branch directly from the central Sahara to the central Nigerian savannas.

Journal of Archaeological Science: Reports, 2021

Recent archaeobotanical analysis revealed that the botanical remains from the site of Tongo Maaré Diabal (Mali) are composed primarily of pearl millet remains (up to 85%). Contemporaneous West African sites (500-1200 Cal AD) usually display more diverse patterns, especially by the end of this period. Indeed, contemporary urban sites of the West African Sahel often comprise combined and diversified farming systems of millet (Pennisetum glaucum), African rice (Oryza glaberrima), sorghum (Sorghum bicolor), Echinochloa sp. and fonio (Digitatia exilis). This article seeks to explain the near-exclusive focus of Tongo Maaré Diabal's agricultural economy on millet, particularly with regard to the site's status as a settlement of iron workers.

Language is not only a vehicle for the transmission of culture, but a culture medium of a sort on which culture thrives and is preserved simultaneously. The strength of language data is its amenability to analysis devoid of sentiments. If analysed with the right tool, it can "unearth" rich and refreshing cultural history in the "fashion" of archaeology. This paper will illustrate and review the methodology. The link between archaeology and linguistics in Nigeria is yet to reach the level that will be obvious to practitioners from both disciplines. However, there are positive developments that we need to be aware. Recent findings from archaeology in Nigeria and elsewhere are closing up the gap scholars have hoped for. Historical linguistics attempts to locate probable homelands for speakers of languages that are represented by genetic family trees. Archaeology is expected to follow up on such a lead to find historical evidence of the material culture of the peoples who inhabited the probable homelands. The use of the simple technique of floatation in archaeology for processing soil samples from excavation sites is a breakthrough. The analysis of such samples from Southern Kaduna in the cradle of the Nok complex has yielded an array of seeds of ancient crops. The existence of bulrush millet from the Nok archaeological finds and elsewhere has the potential of confirming or refuting claims of historical linguistics.

African Archaeological Review, 2021

Imprints of domesticated pearl millet (Pennisetum glaucum (L.) R. Br.) spikelets, observed as temper in ceramics dating to the third millennium BC, provide the earliest evidence for the cultivation and domestication process of this crop in northern Mali. Additional sherds from the same region dating to the fifth and fourth millennium BC were examined and found to have pearl millet chaff with wild morphologies. In addition to studying sherds by stereo microscopy and subjecting surface casts to scanning electron microscopy (SEM), we also deployed X-ray micro-computed tomography (microCT) on eleven sherds. This significantly augmented the total data set of archaeological pearl millet chaff remains from which to document the use of the wild pearl millet as ceramic temper and the evolution of its morphology over time. Grain sizes were also estimated from spikelets preserved in the ceramics. Altogether, we are now able to chart the evolution of domesticated pearl millet in western Africa using three characteristics: the evolution of non shattering stalked involucres ; the appearance of multiple spikelet involucres, usually paired spikelets; and the increase in grain size. By the fourth millennium BC, average grain breadth had increased by 28%, although spikelet features otherwise resemble the wild type. In the third millennium BC, the average width of seeds is 38% greater than that of wild seeds, while other qualitative features of domestication are indicated by the presence of paired spikelets and the appearance of non dehiscent, stalked involucres. Non shattering spikelets had probably become fixed by around 2000 BC, while increases in average grain size continued into the second millennium BC. These data now provide a robust sequence for the morphological evolution of domesticated pearl millet, the first indigenous crop domesticated in western Africa. Résumé: Des empreintes d’épillets de mil domestiqué (Pennisetum glaucum (L.) R. Br.) observées dans des céramiques datées du 3e millénaire av. J.-C. provenant du nord du Mali constituent les plus anciens témoins de la mise en culture et de la domestication de cette céréale. Des tessons supplémentaires issus de la même région se rapportant aux 5e et 4e millénaires av. J.-C. ont été examinés et ont révélé des empreintes de balle de mil de morphologies sauvages. En plus de l’observation de leurs surfaces par stéréo-microscopie, et de l’observation des moulages d’empreintes au microscope à balayage, onze d’entre eux ont fait l’objet de microtomographies aux rayons X (microCT). Ces examens enrichissent considérablement l’ensemble des données archéologiques concernant l’utilisation du mil sauvage comme dégraissant végétal et son évolution morphologique à travers le temps. La taille des grains a aussi été estimée à partir des épillets conservés dans la céramique. En tenant compte des données enregistrées lors d’études antérieures, nous pouvons désormais retracer l’évolution du mil domestiqué en Afrique de l’Ouest à travers trois caractéristiques : l’évolution des involucres pédonculés à égrenage non-spontané; l’apparition d’involucres multiples par épillets, des épillets appariés le plus souvent; l’augmentation de la taille des grains au vu de leur largeur. Déjà au 4e millénaire avant J.-C., la largeur moyenne des grains a augmenté de 28% bien que les caractéristiques de l'épillet ressemblent au type sauvage. Au 3e millénaire avant J.-C., elle est 38% supérieure à celle du morphotype sauvage, tandis que des caractéristiques qualitatives de la domestication sont avérées par la présence d’épillets appariés et par celle d’involucres pédonculés à égrenage nonspontané. La non-déhiscence des épillets est un caractère de domesticité qui s’est probablement fixé vers 2000 avant J.-C. L’augmentation de la taille moyenne des grains s’est poursuivie tout au long du 2e millénaire av. J.-C. Ces données fournissent désormais une séquence robuste concernant l’évolution morphologique du mil, la première céréale indigène domestiquée en Afrique de l’Ouest.

Plants and People in the African Past, 2018

Carbonized plant remains and plant impressions in burnt clay pieces, recovered during archaeological excavation and survey of two sites in East Sudan, were subjected to archaeobotanical investigation. Analysed samples have provided evidence for plant use and cultivation of sorghum alongside the use of a range of other taxa. The results from this study illustrate that as late as the early second millennium BC, the inhabitants of Kassala were still exploiting a mixture of morphologically wild and domesticated Sorghum bicolor. The evidence suggests that while the domestication process of sorghum was underway, full domestication may not have been reached at this time. We can hence classify this as part of the pre-domestication cultivation stage for Sorghum bicolor, which can be inferred to have begun at least two thousand years earlier. Wild taxa that may also have been exploited for food include Brachiaria sp., Rottboellia cochinchinensis (itchgrass), and apparently mixed wild and domesticated Pennisetum glaucum (pearl millet). This study also provides the first archaeobotanical evidence for Adansonia digitata (baobab) in northeastern Africa. Taken together these data suggest that Kassala was part of an early core area for sorghum domestication and played an important role in the diffusion of Africa crops including pearl millet to Asia.