Charlene Murphy

Between China and South Asia: A Middle Asian corridor of crop dispersal and agricultural innovation in the Bronze Age

The period from the late third millennium BC to the start of the first millennium AD witnesses the first steps towards food globalization in which a significant number of important crops and animals, independently domesticated within China, India, Africa and West Asia, traversed Central Asia greatly increasing Eurasian agricultural diversity. This paper utilizes an archaeobotanical database (AsCAD), to explore evidence for these crop translocations along southern and northern routes of interaction between east and west. To begin, crop translocations from the Near East across India and Central Asia are examined for wheat (Triticum aestivum) and barley (Hordeum vulgare) from the eighth to the second millennia BC when they reach China. The case of pulses and flax (Linum usitatissimum) that only complete this journey in Han times (206 BC–AD 220), often never fully adopted, is also addressed. The discussion then turns to the Chinese millets, Panicum miliaceum and Setaria italica, peaches (Amygdalus persica) and apricots (Armeniaca vulgaris), tracing their movement from the fifth millennium to the second millennium BC when the Panicum miliaceum reaches Europe and Setaria italica Northern India, with peaches and apricots present in Kashmir and Swat. Finally, the translocation of japonica rice from China to India that gave rise to indica rice is considered, possibly dating to the second millennium BC. The routes these crops travelled include those to the north via the Inner Asia Mountain Corridor, across Middle Asia, where there is good evidence for wheat, barley and the Chinese millets. The case for japonica rice, apricots and peaches is less clear, and the northern route is contrasted with that through northeast India, Tibet and west China. Not all these journeys were synchronous, and this paper highlights the selective long-distance transport of crops as an alternative to demic-diffusion of farmers with a defined crop package.

Evidence for Sorghum Domestication in Fourth Millennium BC Eastern Sudan: Spikelet Morphology from Ceramic Impressions of the Butana Group

Since the 1970s, the quest for finding the origins of domesticated sorghum in Africa has remained elusive despite the fact that sorghum (Sorghum bicolor (L.) Moench. sensu stricto) is one of the world’s most important cereals. Recognized as originating from wild populations in Africa (Sorghum arundinaceum (Desv.) Stapf), however, the date and cultural context of its domestication has been controversial, with many scholars inferring an early Holocene origin in parallel with better-known cereal domestications. This paper presents firm evidence that the process of domesticating sorghum was present in the far eastern Sahel in the southern Atbai at an archaeological site associated with the Butana Group. Ceramic sherds recovered from excavations undertaken by the Southern Methodist University Butana Project during the 1980s from the largest Butana Group site, KG23, near Kassala, eastern Sudan, were analyzed, and examination of the plant impressions in the pottery revealed diagnostic chaff in which both domesticated and wild sorghum types were identified, thus providing archaeobotanical evidence for the beginnings of cultivation and emergence of domesticated characteristics within sorghum during the fourth millennium BC in eastern Sudan.

Finding millet in the Roman world

Examining the evidence for millet in the Roman empire, during the period, circa 753 bc–610 ad, presents a number of challenges: a handful of scant mentions in the ancient surviving agrarian texts, only a few fortuitous preserved archaeological finds and limited archaeobotanical and isotopic evidence. Ancient agrarian texts note millet’s ecological preferences and multiple uses. Recent archaeobotanical and isotopic evidence has shown that millet was being used throughout the Roman period. The compiled data suggests that millet consumption was a more complex issue than the ancient sources alone would lead one to believe. Using the recent archaeobotanical study of Insula VI.I from the city of Pompeii, as a case study, the status and role of millet in the Roman world is examined and placed within its economic, cultural and social background across time and space in the Roman world.

The origins and early dispersal of horsegram (Macrotyloma uniflorum), a major crop of ancient India

Horsegram has been an important crop since the beginning of agriculture in many parts of South Asia. Despite horsegram’s beneficial properties as a hardy, multi-functional crop, it is still regarded as a food of the poor, particularly in southern India. Mistakenly regarded as a minor crop, largely due to entrenched biases against this under-utilised crop, horsegram has received far less research than other pulses of higher status. The present study provides an updated analysis of evidence for horsegram’s origins, based on archaeological evidence, historical linguistics, and herbarium collections of probable wild populations. Our survey of herbarium specimens provides an updated map of the probable range of the wild progenitor. A large database of modern reference material provides an updated baseline for distinguishing wild and domesticated seeds, while an extensive dataset of archaeological seed measurements provides evidence for regional trends towards larger seed size, indicating domestication. Separate trends towards domestication are identified for north-western India around 4000 BP, and for the Indian Peninsula around 3500 BP, suggesting at least two separate domestications. This synthesis provides a new baseline for further germplasm sampling, especially of wild populations, and further archaeobotanical data collection.

Seed coat thinning during horsegram ( Macrotyloma uniflorum ) domestication documented through synchrotron tomography of archaeological seeds

Reduction of seed dormancy mechanisms, allowing for rapid germination after planting, is a recurrent trait in domesticated plants, and can often be linked to changes in seed coat structure, in particular thinning. We report evidence for seed coat thinning between 2,000 BC and 1,200 BC, in southern Indian archaeological horsegram (Macrotyloma uniflorum), which it has been possible to document with high precision and non-destructively, through high resolution x-ray computed tomography using a synchrotron. We find that this trait underwent stepped change, from thick to semi-thin to thin seed coats, and that the rate of change was gradual. This is the first time that the rate of evolution of seed coat thinning in a legume crop has been directly documented from archaeological remains, and it contradicts previous predictions that legume domestication occurred through selection of pre-adapted low dormancy phenotypes from the wild.

A tale of two rice varieties: Modelling the prehistoric dispersals of japonica and proto-indica rices:

We model the prehistoric dispersals of two rice varieties, japonica and proto-indica, across Asia using empirical evidence drawn from an archaeobotanical dataset of 400 sites from mainland East, Southeast and South Asia. The approach is based on regression modelling wherein goodness of fit is obtained from log–log quantile regressions of the archaeologically inferred age versus a least-cost distance from the origin(s) of dispersal. The Fast Marching method is used to estimate the least-cost distances based on simple geographical features. We explicitly test three hypotheses for the arrival of japonica rice to India where, it has been proposed, it hybridized with the indigenous proto-indica, subsequently spreading again throughout India. Model selection, based on information criteria, highlights the role of the Inner Asia Mountain Corridor in introducing japonica rice into northeast India, followed closely by a ‘mixed-route’ model, where japonica was also almost simultaneously introduced via Assam, Bangladesh and Myanmar. Finally, we estimate the impact of future archaeological work on model selection, further strengthening the importance of the Inner Asia Mountain Corridor.

Evidence of Sorghum Cultivation and Possible Pearl Millet in the Second Millennium BC at Kassala, Eastern Sudan

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.