Skip to main content

Advertisement

Log in

Variability and preservation biases in the archaeobotanical record of Eleusine coracana (finger millet): evidence from Iron Age Kenya

  • Original Article
  • Published:
Vegetation History and Archaeobotany Aims and scope Submit manuscript

Abstract

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.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

Data availability

Source data is available upon request from the corresponding author.

Notes

  1. Technically, these are caryopses: the dry, one-seeded fruits of a grass. We will use the more commonly understood words “grain” or “seed” interchangeably with caryopsis in this paper for the sake of clarity. Likewise, the diagnostic surface textures of these grains, described below and illustrated in Fig. 2, are those of the adhering caryopsis coat. We will use “grain surface texture” or caryopsis coat to describe this feature (Esau 1965, p. 592).

References

  • Ambrose SH, Collett D, Collett D, Marshall F (1984) Excavations at Deloraine, Rongai, 1978. Azania 19:79–104

    Article  Google Scholar 

  • Asfaw Z (1989) Relationships between spike morphology, hordeins and altitude within Ethiopian barley, Hordeum vulgare L. (Poaceae). Hereditas 110:203–209

    Article  Google Scholar 

  • Barron A, Fuller DQ, Stevens C, Champion L, Winchell F, Denham T (2020) Snapshots in time: MicroCT scanning of pottery sherds determines early domestication of sorghum (Sorghum bicolor) in East Africa. J Archaeol Sci 123:105259. https://doi.org/10.1016/j.jas.2020.105259

    Article  Google Scholar 

  • Beldados A (2016) Paleoethnobotanical study of ancient food crops and the environmental context in North-East Africa, 6000 BC-AD 200/300. (Cambridge Monographs in African Archaeology 88, BAR International Series 2206). BAR Publishing, Oxford

  • Beldados A (2019) Millets in eastern Sudan: an archaeobotanical study. Azania 54:501–515. https://doi.org/10.1080/0067270X.2019.1691844

    Article  Google Scholar 

  • Belton PS, Taylor JRN (2004) Sorghum and millets: protein sources for Africa. Trends Food Sci Technol 15:94–98. https://doi.org/10.1016/j.tifs.2003.09.002

    Article  Google Scholar 

  • Bisht M, Mukai Y (2001) Genomic in situ hybridization identifies genome donor of finger millet (Eleusine coracana). Theor Appl Genet 102:825–832

    Article  Google Scholar 

  • Blum A, Sullivan CY (1986) The comparative drought resistance of landraces of sorghum and millet from dry and humid regions. Ann Bot 57:835–846

    Article  Google Scholar 

  • Boardman S (2000) Archaeobotany. In: Philipson DW (ed) Archaeology of Aksum, Ehtiopia, 1993–7, vol 2. British Institute in Eastern Africa, London, pp 363–368

    Google Scholar 

  • Boardman S, Jones G (1990) Experiments on the effects of charring on cereal plant components. J Archaeol Sci 17:1–11

    Article  Google Scholar 

  • Boivin N, Fuller DQ (2009) Shell middens, ships and seeds: exploring coastal subsistence, maritime trade and the dispersal of domesticates in and around the ancient Arabian Peninsula. J World Prehist 22:113–180

    Article  Google Scholar 

  • Boivin N, Crowther A, Prendergast M, Fuller DQ (2014) Indian Ocean food globalisation and Africa. Afr Archaeol Rev 31:547–581

    Article  Google Scholar 

  • Crowther A, Lucas L, Helm R et al (2016) Ancient crops provide first archaeological signature of the westward Austronesian expansion. Proc Natl Acad Sci USA 113:6,635–6,640

    Article  Google Scholar 

  • Crowther A, Prendergast ME, Fuller DQ, Boivin N (2018) Subsistence mosaics, forager-farmer interactions, and the transition to food production in eastern Africa. Quat Int 489:101–120

    Article  Google Scholar 

  • D’Andrea AC (2008) T’ef (Eragrostis tef) in ancient agricultural systems of highland Ethiopia. Econ Bot 62:547–566

    Article  Google Scholar 

  • Demissie A, Bjørnstad Å (1996) Phenotypic diversity of Ethiopian barleys in relation to geographical regions, altitudinal range, and agro-ecological zones: as an aid to germplasm collection and conservation strategy. Hereditas 124:17–29

    Article  Google Scholar 

  • Dida MM, Ramakrishnan S, Bennetzen JL, Gale MD, Devos KM (2007) The genetic map of finger millet, Eleusine coracana. Theor Appl Genet 114:321–332

    Article  Google Scholar 

  • Dida MM, Wanyera N, Dunn MLH, Bennetzen JL, Devos KM (2008) Population structure and diversity in finger millet (Eleusine coracana) germplasm. Tropical Plant Biol 1:131–141

    Article  Google Scholar 

  • Esau K (1965) Plant anatomy, 2nd edn. Wiley, New York

    Google Scholar 

  • Fuller DQ (2006) Agricultural origins and frontiers in South Asia: a working synthesis. J World Prehist 20:1–86

    Article  Google Scholar 

  • Giblin JD, Fuller DQ (2011) First and second millennium A.D. agriculture in Rwanda: archaeobotanical finds and radiocarbon dates from seven sites. Veget Hist Archaeobot 20:253–265

    Google Scholar 

  • Gimode D, Odeny DA, de Villiers EP et al (2016) Identification of SNP and SSR markers in finger millet using next generation sequencing technologies. PLoS ONE 11:e0159437

    Article  Google Scholar 

  • Gowlett JAJ, Hedges REM, Law IA, Perry C (1987) Radiocarbon dates from the Oxford AMS System: archaeometry datelist 5. Archaeometry 29:125–155

    Article  Google Scholar 

  • Gupta SM, Arora S, Mirza N et al (2017) Finger Millet: a “certain” crop for an “uncertain” future and a solution to food insecurity and hidden hunger under stressful environments. Front Plant Sci 8:643. https://doi.org/10.3389/fpls.2017.00643

    Article  Google Scholar 

  • Harlan JR (1971) Agricultural origins: centers and noncenters. Science 174:468–474

    Article  Google Scholar 

  • Hilu KW, de Wet JMJ (1976a) Racial evolution in Eleusine coracana ssp. coracana (finger millet). Am J Bot 63:1,311–1,318

    Article  Google Scholar 

  • Hilu KW, de Wet JMJ (1976b) Domestication of Eleusine coracana. Econ Bot 30:199–208

    Article  Google Scholar 

  • Hilu KW, Johnson JL (1992) Ribosomal DNA variation in finger millet and wild species of Eleusine (Poaceae). Theor Appl Genet 83:895–902

    Article  Google Scholar 

  • Hilu KW, de Wet JMJ, Harlan JR (1979) Archaeobotanical studies of Eleusine coracana ssp. coracana (finger millet). Am J Bot 66:330–333

    Article  Google Scholar 

  • Hogg AG, Heaton TJ, Hua Q et al (2020) SHCal20 Southern Hemisphere calibration, 0–55,000 years cal BP. Radiocarbon 62(4):759–778

    Article  Google Scholar 

  • Kebebew F, Tsehaye Y, McNeilly T (2001) Morphological and farmers cognitive diversity of barley (Hordeum vulgare L.[Poaceae]) at Bale and North Shewa of Ethiopia. Genet Resour Crop Evol 48:467–481

    Article  Google Scholar 

  • Klee M, Zach B, Neumann K (2000) Four thousand years of plant exploitation in the Chad Basin of northeast Nigeria I: the archaeobotany of Kursakata. Veget Hist Archaeobot 9:223–237

    Article  Google Scholar 

  • Klee M, Zach B, Stika H-P (2004) Four thousand years of plant exploitation in the Lake Chad Basin (Nigeria), part III: plant impressions in potsherds from the Final Stone Age Gajiganna Culture. Veget Hist Archaeobot 13:131–142

    Article  Google Scholar 

  • Lange G (1991) Appendix V: a seed of wild finger millet from Gogo Falls. In: (Robertshaw P) Gogo Falls: excavations at a complex archaeological site east of Lake Victoria. Azania 26:191–192

  • Lavé J, Wenger E (1991) Situated learning: Legitimate peripheral participation. Cambridge University Press, Cambridge

    Book  Google Scholar 

  • Lule D, Tesfaye K, Fetene M, de Villiers S (2012) Multivariate analysis for quantitative traits in finger millet (Eleusine coracana subsp. coracana) population collected from eastern and southeastern Africa: detection for patterns of genetic diversity. Int J Agric Res 7:303–314

    Article  Google Scholar 

  • Lule D, de Villiers S, Fetene M, Odeny DA, Rathore A, Das RR, Tesfaye K (2018) Genetic diversity and association mapping of Ethiopian and exotic finger millet accessions. Crop Pasture Sci 69:879–891

    Article  Google Scholar 

  • Manning K, Pelling R, Higham T, Schwenniger J-L, Fuller DQ (2011) 4500-year old domesticated pearl millet (Pennisetum glaucum) from the Tilemsi Valley, Mali: new insights into an alternative cereal domestication pathway. J Archaeol Sci 38:312–322

    Article  Google Scholar 

  • Manyasa EO, Tongoona P, Shanahan P, Mgonja MA, de Villiers S (2015) Genetic diversity in East African finger millet (Eleusine coracana (L.) Gaertn) landraces based on SSR markers and some qualitative traits. Plant Genet Resour 13:45–55

    Article  Google Scholar 

  • Märkle T, Rösch M (2008) Experiments on the effects of carbonization on some cultivated plant seeds. Veget Hist Archaeobot 17:257–263

    Article  Google Scholar 

  • Mueller NG (2017) Carbonization, differential preservation, and sampling bias in domestication studies: an erect knotweed (Polygonum erectum L.) case study. J Archaeol Sci Rep 13:303–311

    Google Scholar 

  • Murray SS (2004) Searching for the origins of African rice domestication. Antiquity 78:1–3

    Google Scholar 

  • Nazarea VD (2005) Heirloom seeds and their keepers: marginality and memory in the conservation of biological diversity. University of Arizona Press, Tuscon

    Book  Google Scholar 

  • Odak O (1977) Kakapeli and other recently discovered rock paintings in the Western Highlands of Kenya. Azania 12:187–192

    Article  Google Scholar 

  • Odak O (1980) Recent fieldwork in west Kenya. Nyame Akuma 16:10–14

    Google Scholar 

  • Pautasso M, Aistara G, Barnaud A et al (2013) Seed exchange networks for agrobiodiversity conservation: a review. Agron Sustain Dev 33:151–175

    Article  Google Scholar 

  • Phillipson DW (1977) The excavation of Gobedra rock-shelter, Axum: an early occurrence of cultivated finger millet in northern Ethiopia. Azania 12:53–82

    Article  Google Scholar 

  • Phillipson DW (2000) The Appendix VI. In: Phillipson DW (ed) The archaeology at Aksum, Ethiopia, 1993–7, vol 2. The British Institute of Eastern Africa, London, pp 504–506

    Google Scholar 

  • Prendergast ME, Lipson M, Sawchuk EA et al (2019) Ancient DNA reveals a multistep spread of the first herders into sub-Saharan Africa. Science 365:eaaw6275

    Article  Google Scholar 

  • Reimer PJ, Austin WEN, Bard E et al (2020) The IntCal20 Northern Hemisphere radiocarbon age calibration curve (0–55 cal kBP). Radiocarbon 62:725–757. https://doi.org/10.1017/RDC.2020.41

    Article  Google Scholar 

  • Robertshaw P (1991) Gogo falls: excavations at a complex archaeological site east of Lake Victoria. Azania 26:63–195

    Article  Google Scholar 

  • Teshome A, Fahrig L, Torrance JK, Lambert JD, Arnason TJ, Baum BR (1999) Maintenance of sorghum (Sorghum bicolor, Poaceae) landrace diversity by farmers’ selection in Ethiopia. Econ Bot 53:79–88

    Article  Google Scholar 

  • Tropicos (2020) Tropicos org. Missouri Botanical Garden. https://tropicos.org. Accessed Oct 2020

  • Tsehaye Y, Berg T, Tsegaye B, Tanto T (2006) Farmers’ management of finger millet (Eleusine coracana L.) diversity in Tigray, Ethiopia and implications for on-farm conservation. Biodivers Conserv 15:4,289–4,308

    Article  Google Scholar 

  • Walshaw SC (2010) Converting to rice: urbanization, Islamization and crops on Pemba Island, Tanzania, AD 700–1500. World Archaeol 42:137–154. https://doi.org/10.1080/00438240903430399

    Article  Google Scholar 

  • Wang K, Goldstein S, Bleasdale M et al (2020) Ancient genomes reveal complex patterns of population movement, interaction, and replacement in sub-Saharan Africa. Sci Adv 6:eaaz0183

    Article  Google Scholar 

  • Winchell F, Stevens CJ, Murphy C, Champion L, Fuller DQ (2017) Evidence for sorghum domestication in fourth millennium BC eastern Sudan: spikelet morphology from ceramic impressions of the Butana Group. Curr Anthropol 58:673–683

    Article  Google Scholar 

  • Wright PJ (2003) Preservation or destruction of plant remains by carbonization? J Archaeol Sci 30:577–583. https://doi.org/10.1016/S0305-4403(02)00203-0

    Article  Google Scholar 

  • Wright PJ (2008) Understanding the carbonization and preservation of sunflower and sumpweed remains. MidCont J Archaeol 33:139–153

    Article  Google Scholar 

  • Young R, Thompson G (1999) Missing plant foods? Where is the archaeobotanical evidence for sorghum and finger millet in East Africa? In: van der Veen M (ed) The exploitation of plant resources in Ancient Africa. Kluwer Academic/Plenum Publishers, New York, pp 63–72

    Chapter  Google Scholar 

  • Zach B, Klee M (2003) Four thousand years of plant exploitation in the Chad Basin of NE Nigeria II: discussion on the morphology of caryopses of domesticated Pennisetum and complete catalogue of the fruits and seeds of Kursakata. Veget Hist Archaeobot 12:187–204

    Article  Google Scholar 

  • Zhang H, Hall N, Goertzen LR, Chen CY, Peatman E, Patel J, McElroy JS (2019) Transcriptome analysis reveals unique relationships among Eleusine species and heritage of Eleusine coracana. Genes Genomes Genet 9:2,029–2,036

    Google Scholar 

Download references

Acknowledgements

The authors would like to thank all of the participants in the 2018 field season at Kakapel, Emmanuel Ndiema, Christine Ogola, and Anthony Odera and the staff of the National Museums of Kenya for facilitating this research and the analysis of this material, and Megan Belcher for her assistance with the carbonization experiment.

Funding

This research was supported by funds provided by the Max Planck Institute for the Science of Human History.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Natalie G. Mueller.

Ethics declarations

Conflict of interest

The authors declare no conflicts of interest or competing interests.

Additional information

Communicated by K. Neumann.

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mueller, N.G., Goldstein, S.T., Odeny, D. et al. Variability and preservation biases in the archaeobotanical record of Eleusine coracana (finger millet): evidence from Iron Age Kenya. Veget Hist Archaeobot 31, 279–290 (2022). https://doi.org/10.1007/s00334-021-00853-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00334-021-00853-y

Keywords

Navigation