11 Archaeobotany : Its relevance in reconstruction of agricultural history

Ravi Korisettar

Objectives

This chapter deals with the relevance of archaeobotany and its importance in the archaeology of early food producing cultures of the Indian subcontinent. The role of archaeobotany is the main focus of this chapter. It deals with the botanical remains found from findings from excavations in India and Pakistan. Further, it also discusses how application of archaeobotany helps in generating new knowledge of past human populations.

 Introduction

The survival of human communities in any given environment is dependent on their ability to ensure the availability of food. Hunter-gatherers procure food through extraction from wild resources (through hunting, plant gathering, scavenging, fishing and fowling). For most of the Palaeolithic period hominins obtained their food through hunting gathering from available wild animals and plant food resources. Archaeological record of the Terminal Pleistocene (late Upper Palaeolithic / Epipalaeolithic) reveals the transition from food gathering to agricultural way of life. This change was characterized by the deliberate manipulation of plant and animal food resources through domestication and cultivation of select plants and animals (stock-raising), thus laying the foundation for agricultural way of life. The scope was limited to their availability in the environment of habitation. This phase of transition in human history has been considered a great turning point that led to the evolution of new plant forms, domesticated crops, surplus food and civilization.

The period between 12,000 and 4,000 BP witnessed the transition of prehistoric hunter-gatherers to village based first farmers and herders in different geographical regions of the Old World. This time bracket covers a series of events leading to the formation of the complete package of food crops that characterizes the food habits of the inhabitants of the subcontinent and elsewhere in the Old World. Regional dietary habits that once formed the distinctiveness of various culture-historic divisions disappeared during the last five thousand years with the rise of intensive agriculture.

2. What is Archaeobotany

Archaeobotany deals with the origins of plant domestication based on recovery of plant remains from archaeological contexts, their identification in the laboratory followed by processual interpretation of culture change as well as morphological changes in cultivated plants. Morphological changes in plants are attributed to adaptations to systems of cultivation and human harvesting. It is also observed that these changes, would have first appeared during a period of pre-domestication cultivation when human behaviours modified the environments and reproductive cycles of plants, especially by the human intervention in the dispersal of seeds.’

During the early days of the development of this area of study it used to be referred to as palaethnobotany which focused on the study of remains of plants cultivated or utilized by man in prehistoric times, since Neolithic times. Palaeoethnobotany is concerned with the analysis and interpretation of archaeobotanical remains in order to reconstruct the nature of interaction of humans and plants in terms of how plants are used as fields, foods, medicines or in ritual, how seasonality of plant availability affects settlement systems, the extent and nature of man-plant interdependency and the impact of humans on plants. Another term archaeoethnobotany was also used to refer to identification of plant remains retrieved from excavations in connection with cultural associations and radiocarbon dating. Later archaeobotany came to be used, which refers to study of plant remains derived from archaeological contexts. It refers to recovery and identification of plants by specialists from Palaeolithic to the modern times.

Archaeobotany combines botanical knowledge with archaeological materials. Botanical remains include two broad categories of evidence – seeds, wood, parenchyma tissue and plant impression, these are macroscopic. The microscopic remains are pollen, phytoliths and diatoms and palaofaeces (coprolites, for e.g.). Archaeobotanists examine such remains from two different perspectives (1) botanical and (2) archaeological. The botanical questions include plant ecology, domestication morphology and the role of human impacts on plant communities and environment. Archaeological perspective examines the (a) nature of resources in terms of wild plant and animal resources in the region of exploitation; (b) site seasonality and subsistence scheduling, presence or absence of cultivation, methods of cultivation; (c) status difference in diet, or access to plant materials; (d) trade in plant products and food stuffs; (e) methods of preparing the food and (f) context of consumption.

Archaeobotanist would equip himself with additional information that can be obtained from a knowledge of the seasonal availability and accessibility of plant food resources in terms of (a)  nearest wild relatives of domesticated species; (b) modern ecological and geographical distribution of wild relatives of domesticated crops; and probable distribution of these species on the basis of their modern distribution and known palaeoenvironmental evidence for the period prior to and during the beginnings of agriculture. Archaeological evidence for agricultural way of life includes food processing implements such as ground stone tools, querns, grinding stones, bedrock mortars, pit silos/granaries and such other artifacts indicating grain processing and vegetal food processing constitute good evidence of agriculture yet remain indirect evidence.

3. Sampling

Archaeobotanical field and laboratory methods were well developed in America and Europe by the 1960s.Other than launching archaeological investigations at organized excavations focussed archaeobotanical research involves digging trial trenches or small test pits at several early agricultural settlements that can provide a stratigraphic sequence of material culture and soils for recovery of plant remains through flotation. Sometimes large amounts of soil samples are required to be able to recover micro and macro botanical remains. In the early days flotation of soils was generally carried out as a laboratory procedure but later it was shifted to excavation sites. As smaller and less conspicuous seeds could easily missed in collections made by hand flotation is the best method. Samples for phytolith collection are also made at this time.

Several kilos of soil samples (10-15 cm thick) are collected and transferred to bags. Simple bucket flotation is carried out and the sieved through 500 mesh that would not retain the majority of clay and sand particles. After the soil is placed in the bucket a small quantity of detergent is added to deflocculate the sediment clays and after adding water thorough mixing is carried out and filtered through the mesh (nylon mesh). This is repeated till it is confirmed that all light weight material is emptied from the soil. The remaining soil is to a large sieve with 1 mm sieve mesh so that less buoyant organic material (charcoal) is recovered.

Rigorous laboratory procedures are followed for identification of charred grains, with help from reference collection of all verities of seed morphology based on charring experiments. Initially the grains are identified based on external morphology. Basin anatomical structure of grains provide additional criteria for specific identification. Scanning Electron Microscopy is also carried out for comparing the cell pattern and surface patterning of grains.

4. Archaeobotany in India

Problem oriented archaeobotanical research in India is relatively late. The mid-1960s onwards application of scientific techniques both in excavations and data analyses, with focus on bioarchaeological remains, started with Harppan and Chalcolithic archaeology of western India. Excavations at Inamgaon in Maharshtra particularly addressed this issue of archaeobotany with a fulfledged archaeobotanist working on the material. Until this time most archaeobotanical research was incidental in Indian archaeology, though problem oriented archaeology was advocated by R.E.M. Wheeler, it was largely restricted to culture historic issues. Flotation was first carried out at Daimabad, Naikund and Inamgaon and later it was extended to other sites across the country, including Harappan sites.

The early change in plant economy and development of early agriculture in the subcontinent can best be understood against the background of early developments in two distinct geographical regions: Southwest Asia and East Asia. In comparison with these two regions, agriculture comes to the subcontinent relatively late, as attested by archaeological and radiocarbon dating. During the last three decades the archaeology of the Neolithic/Chalcolithic cultures in these regions has focused on the role of climate, environmental change and demography in the rise and development of an agricultural way of life. To date, the best documentation of the transition from hunting and gathering to sedentary agricultural way of life has been documented through excavations and multidisciplinary analyses. The archaeology of the Neolithic in these regions is important because many cultivars documented from the subcontinent’s Neolithic/Chalcolithic cultures were introduced either from the Southwest Asia, Africa or East Asia.

The radiocarbon chronology of Southwest Asian and East Asian Neolithic sites has delineated a rapid development of socio-economic changes. The time-scales developed by the excavators suggest that very little time separates the first village farming communities from the first urban civilizations, and then from the first industrial civilizations. The radiocarbon chronology has also clearly established the fact that it was in Southwest Asia that neolithisation first arose, without any external influence. All other early centers of Neolithic cultures experience the “Neolithic Revolution” later, with diffusion and migration playing important roles in the development of staple food crops in contiguous geographical regions: “episodes of human movement occurred from time to time… as different populations developed or adopted agriculture and then spread farming, languages, and genes, in some cases across vast distances”.

The archaeobotanical record of the subcontinent presents a complex suite of indigenous and introduced cultivated crops ranging in time from the Neolithic to Early Historic. The African millets and legumes were first introduced to the Harappan Civilization through a maritime contact between Mesopotamia and the Greater Indus valley. The two main millets from Africa, sorghum and pearl millet, were introduced around 2,000 BC. The African legumes, cowpea (Vigna unguiculata) and hyacinth bean (Lalab purpureus), were introduced during Late Harappan times (1,800-1,300 BC). Finger millet is another African crop (Ethiopian origin), known from south Indian Neolithic after 1000 BC (early Iron Age).

Among the East Asian crops the most important is Asian rice (Oryza sativa),a domesticate from the Yangzi basin of China. Two other millets of external origin found in Protohistoric and later Prehistoric contexts include foxtail millet (Setaria italica) from the Yellow River valley of China and broomcorn millet (Panicum miliaceum), a Central Asia domesticate.

Domesticated crops native to the subcontinent were small millets, pulses and legumes. Black gram, greengram (Vigna sp.) and horsegram are known from the Ghats region and the Deccan plateau. Minor millets belonging to Paspalum and Chenopodium genera and Brachiaria ramosaand Setaria verticillata are known to have been locally developed in southern India, during the time period from 3000 and 1000 BC.

The Southwest Asian crops cultivated in India include: wheat (Triticum spp.), barley (Hordeum vulgare L. sensu lato), lentils (Lens culinaries Med.), chickpea (Cicer arietinum L.), peas (Pisum satium L.), grass pea (Lathyrus sativus L.) and linseed/flax (Linum usitatissimum L.). Beginning with the Mehrgarh Neolithic these crops were well established by the time of mid- Holocene Harappan Civilization. Africa provided a variety of millets and legumes with their origin in the different geographical regions of northern, central and Sahara Africa. They include: sorghum or great millet (Sorghum bicolor (L.) Moench); Ragi or finger millet (Eleusine coracana (L.) Gaetner); Bajra/ pearl millet (Pennisetum glaucum (L.) R. Br. syn. P. americanum (L.) Leeke, syn. P. typhoides Rich.); Cow pea (Vigna unguiculata (L.) Walp.); Hyacinth bean (Lablab purpureus (L.) Sweet). Introduced crops from Central Asia/China include: foxtail millet (Setaria italicaL.) Beau); proso millet (Panicum miliacum L.); hemp (Cannasis sativus L.); and rice (Oryza sativa L.).

Africa provided a variety of millets and legumes with their origin in the different geographical regions of northern, central and Sahara Africa. They include: sorghum or great millet (Sorghum bicolor (L.) Moench); Ragi or finger millet (Eleusine coracana (L.) Gaetner); Bajra/ pearl millet (Pennisetum glaucum (L.) R. Br. syn. P. americanum (L.) Leeke, syn. P. typhoides Rich.); Cow pea (Vigna unguiculata (L.) Walp.); Hyacinth bean (Lablab purpureus (L.) Sweet).Among the several varieties of sorghum of African origin the bicolor race is reported from Neolithc/Chalcolithic and Harappan contexts. This race is best suited for high rainfall areas, it is found to be grown in the Eastern and Western Ghats high rainfall zones. The Durra race is also widely cultivated in India and Pakistan. Though it is of African origin, its cultivation is much later there. It is speculated that the domestic sorghum may have been evolved in India from the early introduction of a bicolor and that it was reintroduced during the Arab conquests in Africa.

Introduced crops from Central Asia/China include: foxtail millet (Setaria italicaL.) Beau); proso millet (Panicum miliacumL.); hemp (Cannasis sativus L.); and rice (Oryza sativa L.).

Some tree crops were introduced through overland trade in fruits and nuts from 2000 BCE onwards. Also, the Bactrian camel was introduced into the subcontinent. Horses also came, but the antiquity of domestication has become an issue of controversy. Some of the tree crops of the Late Harappan (1,800-1,300BCE) period found in Kashmir are: peaches (Pranus persisa (L.) Batsch.),apricot (Pranus armeniaca L.) and walnut (Juglans regia L.) from Central Asia and west China. Almonds (Amygdalus communis L.) came from Southwest Asia.

Food crops native to north India include rice (Oryza sativa L.), moth bean (Vigna acontifolia (Jacq.) Marchal), black gram (Vigna mungo (L.) Hepper), cucumber (Cucumis sativus L.), ivy gourd (Coccinia grandis (L.) Voigt) and citrus fruits. Rice appears to have been a domesticate in China and north India on two different occasions. Similarly, chicken and water buffalo were domesticated in China and India, independently at different points of time.

Based on the above account of archaeobotanical investigations in the Indian subcontinent eleven major Neolithic/Chalcolithic culture-historic divisions are identified, some of independent agricultural origins and others originating from diffusion:

• Baluchistan and the Indus-Sarasvati Basin: Mehrgarh Tradition
• The Himalayan Region: The Kashmir and Swat Valleys-The Burzahom Tradition
• The Vindhya Region:The Son and Belan Valleys- The Kaimur Tradition
• The Middle Ganga Basin: The Ganga Tradition – an independent center of rice cultivation
• Eastern India:  The Utkal Tradition– an independent centre of rice cultivation
• North Gujarat:The Anarta Tradition – an independent centre of millet agriculture
• The Banas Valley (Eastern Rajasthan):The MewarTradition
• Malwa (The Chambal, Betwa and Narmada Valleys): The Kayatha and Malwa Traditions in Malwa
• West Deccan –The Tapi, Godavari, Upper Krishna and Bhima Valleys: The Deccan Chalcolithic Tradition (Malwa and Jorwe Cultures)
• Mid- Deccan – The Ashmound Tradition- an independent centre  of millet agriculture
• North-Eastern Region: The Brahmaputra Tradition

The Neolithic/Chalcolithic archaeobotanical record from these culture-historic divisions reveals spatial and temporal variation in the rise of agricultural economies. These divisions also reveal distinctiveness in terms of staple crops: wheat and barley in the Indus-Saravati basin; rice in the northeast and Middle Ganga valley; and millets in western and southern India. Some of these zones have been identified as independent centers of agricultural origins. While the northwest of the subcontinent witnessed Early Holocene (7000 BC) transition to subsistence production and its gradual expansion covering the whole of the Indus-Sarasvati basin leading to the emergence of the first urbanization, the rest of the subcontinent continued with hunting and gathering until Mid- to Late Holocene times.

During 3rd and 2nd millennia BC a series of regional Neolithic/Chalcolithic cultures, with clear evidence for mixed subsistence economy, emerged across the rest of the subcontinent, outside the Indus-Sarasvati basin. While some of these regional cultures have been named after a type site or local river, the others have been designated either Neolithic or Chalcolithic (e.g., Ahar-Banas culture in Mewar; Kayatha-Malwa in Malwa, Anarta in Gujarat; Savalda, Malwa-Jorwe in west Deccan; Southern Neolithic in the mid- Deccan; and Vindhyan Neolithic).

5. Summary

During the last seventy years archaeobotanical research in Indian has progressed from strength to strength. A series of regional agricultural traditions have been identified and that the early farming communities adopted various combinations of crops and animals in different parts of subcontinent at different times. Independent centres of agricultural origins have also been identified, these were based on adoption of local millets and pulses prior to the introduction of crops from outside. Village life based on complete package of Southwest Asian, East Asian and indigenous domesticates (both plants and animals) took several thousand years to develop. Several crops have different ecological adaptations and distinct geographical distribution and their introduction into new areas necessitated adaptive measures to ensure productivity.

Ancient agriculture is relatively late in the Indian subcontinent as both archaeological and radiocarbon dating suggest. The Indian subcontinent could never have been an agricultural hotspot. It lies between two major, primary areas of cereal cultivation, Southwest Asia on the west and East Asia on the east. The Indo-Iranian borderlands on the western frontiers of the subcontinent and the northeastern humid landforms on the east are critical geographical areas that appear to have been passages for dispersal of crops and movement of peoples from outside. The Indian Ocean maritime links further added to the exchange of food crops and horticultural items in and out of the subcontinent.

A combination of pastoral and agricultural economies probably contributed to a successful agricultural way of life in the diverse ecosystems across the subcontinent. Both sedentism and cultivation of food crops appear to have started simultaneously in the region. Early farming communities are generally referred to as Neolithic; however, such is not the case in some regions, particularly in western India, where early agriculture is associated with advanced agro-pastoral communities generally referred to as Chalcolithic.

Ancient agriculture in the Indian subcontinent, as elsewhere, is the result of a mixed economy that incorporated cultivation of staple crops and herding. These two components appear to have emerged simultaneously, though one observes spatial variation in the timing of their emergence in the distinctive Neolithic / Chalcolithic provinces across the region. This mixed economy also meant agricultural activities were supplemented by herding cattle/buffalo, stock raising, gathering wild plant foods, hunting, fishing, and harvesting mollusks. Chronologically, the Indian subcontinent presents itself as an area of secondary agricultural origins as compared with the early centers of Near East and Eastern Asia. The temporal span of ancient agriculture in the subcontinent falls between the 7th and 1st millennium BC, as contrasted with 12th millennium BC developments in Southwest Asia and East Asia.

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