Iron Age origins of European Alpine dairy farming

Chemical analysis of organic residues from pottery reveals lipids

Dairy produce from the high Alps is today of enormous economic and cultural importance to the region. The recent history of dairy farming is well-documented, but there is very little in the way of archaeological evidence to attest to its origins. Transhumance (seasonal migration of livestock between pastures) leaves few traces, and the problem is compounded by acidic soils that lead to the deterioration of faunal remains.

Milk production in lowland settings in Europe is documented from the Early Neolithic, and ceramic sieves for separating curds and whey are evidence for the production of cheese and fermented milk products by populations that were still predominantly lactose intolerant. In the Alpine lowlands, there is evidence for dairy farming in the form of lipid residues on pottery vessels from around 6,000 BC. However, it was at this stage part of a generalised mixed farming economy that also included meat production.

From around 3000 BC, it has been speculated that dairy farming intensified as there was a greater reliance on ‘secondary’ animal products such as wool and milk, and greater utilisation of poorer and less accessible land. As noted above, the limited supporting archaeological evidence is not unexpected. Seasonal occupation of high-altitudes intensified from around 2500 BC to 1000 BC and large dry stone enclosures were constructed during this period. They are thought to be livestock pens, but the scarcity of artefacts or faunal remains means that there is no definite clues as to their function. The only ceramics to have been recovered from these sites are small, highly fragmented potsherds.

To investigate further, researchers obtained 30 securely-dated potsherds from six highland archaeological sites of the Engadin region of southern Switzerland. The sites dated from 5000 to 1000 BC. The region is typical of the alpine environment, with valley bottoms above 1,000 m above sea level and high seasonal pastures ranging from around 2,000 m to 2,800 m above sea level. Five of the sites were more than 2,000 m above sea level. They include early Neolithic and Bronze Age rock-shelters and a later Iron Age stone enclosure and hut.

Lipids were successfully extracted in varying amounts from the potsherds, with all the Iron Age pots yielding much higher quantities. Analysis of the lipids using gas chromatography mass spectrometry revealed profiles typical of degraded animal fats. Several Bronze Age and Iron Age potsherds contained ketones with chain lengths consistent with heating of saturated fatty acids, suggesting that the pots were used for heating animal products.

Carbon stable isotope analysis was then applied to fatty acids obtained from 28 of the potsherds. The milk of ruminants and to a lesser extent carcass fat of ruminants, is depleted in carbon-13 relative to other fatty acids. Values obtained were then compared with those obtained from dairy, ruminant and non-ruminant sources. It was found that values for lipids obtained from the Iron Age potsherds were consistent with dairy products. By contrast, the earlier Neolithic and Bronze Age potsherds yielded values consistent with ruminant and non-ruminant animal fats. Dairy farming was identified at all of the Iron Age sites included in the study.

Thus it appears that while low-altitude dairy farming was present from the Neolithic onwards, specialist Alpine dairy farming was a later development. Iron Age alpine pastoralists would have had to face adverse and unpredictable weather, and a significant reduction in the yield and quality of milk. It is likely that pressure on lowland pastures and an increased demand for alpine cheese were motivating factors. This in turn was probably triggered by social and economic changes, deterioration of the climate, and demographic growth during the Late Bronze Age and the Early Iron Age.

Reference:
Carrer, F. et al., Chemical Analysis of Pottery Demonstrates Prehistoric Origin for High-Altitude Alpine Dairying. PLoS One 11 (4), DOI:10.1371/journal.pone.0151442 (2016).

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Radiocarbon dates used to trace possible origins of domesticated rice

Seven models tested against extensive archaeological database

Rice is one of the world’s most important cereal crops, and has supported dense human populations in Asia since Neolithic times. The origin and spread of domesticated rice is understandably of great interest to students of Asian prehistory and researchers have employed a variety of methods, including genetics, phytolith studies, from the presence of charred grains in archaeological excavations, and from rice husks in Neolithic pottery.

In a newly-published study researchers have made use of an extensive database of radiocarbon data from 400 sites spanning 470 phases of occupation in mainland East, Southeast and South Asia. The researchers modelled the likely spread of rice agriculture using an algorithm known as Fast Marching, which was used to estimate least-cost distances based on simple geographical features and suitability of regions for rice agriculture. Existing knowledge of archaeological evidence for rice was used to infer backwards towards probable areas of origin for rice cultivation. The researchers also used goodness of fit to test various previously-published hypotheses of the origin of rice agriculture against the overall archaeological rice database.

The unconstrained search for the most likely origin identified a region between the Lower and Middle Yangtze, specifically the northeast of Jiangxi Province, where there is little archaeobotanical evidence for early rice agriculture. However, the algorithm was trying to find the best-fitting single source and was unable to identify multiple origin scenarios. In such cases, it will highlight an area in between the various true origins.

The next step was to test seven previously-published hypotheses, labelled L1 to L7 in the study:
L1 Ganges, Burma and northern Vietnam
L2 Ganges, Northern Thailand and lower Yangtze
L3 Middle Yangtze and northern Bay of Bengal
L4 Pearl River delta
L5 Middle Yangtze
L6 Lower Yangtze
L7 Middle and Lower Yangtze

Of these, the last model, favouring two independent origins in the Middle and the Lower Yangtze, gave the best fit with the data and is also the most consistent with the unconstrained search. The authors of the report claim that the L7 ‘dual Yangtze’ model is so well supported over the second-best match, the L6 Lower Yangtze scenario, that the situation is compared to randomly drawing 125 million white balls out of an urn and asking whether this is sufficient evidence that the urn contains only white balls, versus containing an equal amount of white and black balls.

Whether such optimism is justified, only time and further studies will tell. However, the results agree with the conclusions of many archaeologists who have recently focused on the Middle and Lower Yangtze basin. There is currently no reason to favour either over the other as a more likely source region of rice domestication episode. Instead, multiple, distinct domestication episodes seems the most plausible hypothesis in the current state of our evidence. Cultural differences between the Neolithic traditions of the Lower and Middle Yangtze, including the earliest preserved field systems, makes it unlikely that rice agriculture diffused between the two regions.

References:
Silva, F. et al., Modelling the Geographical Origin of Rice Cultivation in Asia Using the Rice Archaeological Database. PLoS One 10 (9), e0137024. (2015).

 

 

Ohalo II ‘proto-weeds’ indicate attempts to cultivate wild cereals 23,000 years ago

Evidence of low-level food production at Epipaleolithic site

Ohalo II is a well-studied sedentary hunter-gatherer settlement on the shores of the Sea of Galilee. Associated with the Kebaran culture, the site dates to the Early Epipaleolithic period and was occupied around 23,000 years ago. The partially-excavated site is believed to cover an area of around 2,000 sq. m. (21,500 sq. ft.), and excavations have revealed the remains of six huts. Faunal remains suggest that the Ohalo II people hunted gazelle and deer, trapped hare and birds, and caught fish. From preserved botanical remains, no fewer than 142 different plant species have been identified, including emmer wheat, barley, brome and other small-grained grasses, acorns, almonds, pistachios, olives, legumes, raspberries, figs and grapes. These were collected from a range of habitats, including the nearby Mount Tabor.

In a newly-published report, archaeologists report the identification of 13 plant species now classified as weeds, mixed with large quantities of wild cereal seeds, including emmer, barley and oats. The presence of such species among cereals is considered to be one of the key archaeological indications of food production – in this case some 11,000 years before the onset of full-blown agriculture in the region.

That the Ohalo II people were harvesting wild cereal stands is supported by a study of glossed flint blades found at the site. The pattern of use-wear ‘sickle gloss’ polish observed on the sharp edges of these blades is consistent with their use to harvest wild cereals before they fully ripen and scatter their grain. Such a practice known from the later Natufian culture, but has not previously been documented for the Kebaran.  The blade also bears traces of hafting on the opposite side to the cutting edge, indicating that it was possibly a part of a sickle. Again, such tools are very rare in a pre-Natufian context.

However, the report suggests that these techniques were not carried on in later times, and they evidently represent a failed attempt at low-level food production. Sickle-harvesting did not come into widespread use until the Early Natufian around 8,000 years later, or 15,000 years before the present.

Reference:
x
Snir, A. et al., The Origin of Cultivation and Proto-Weeds, Long Before Neolithic Farming. PLoS One 10 (7), e0131422 (2015).

 

Rice versus wheat agriculture could explain cultural differences within China, claim researchers

Greater interdependency found in rice-growing regions

People living in the rice-growing regions of southern China are more interdependent, loyal, and nepotistic, and less likely to divorce than their counterparts in the wheat-growing regions north of the Yangtze, according to a study published in the journal Science.

Han Chinese students from various regions in the country underwent a series of tests, including the ‘triad task’, which shows subjects lists of three items, such as train, bus, and tracks. They then decide which two items should be paired together. Two of the items (trains and buses) can be paired because they belong to the same category (trains and buses are forms of transport), and two (trains and tracks) because they share a functional relationship (trains run on tracks). Participants from rice-growing regions were more likely to pair the train and the track, whereas those from wheat-growing regions tended to pair the train and the bus.

The so-called ‘rice theory’ is an extension of subsistence style theory, which argues that some forms of subsistence (such as farming) require more functional interdependence than other forms (such as herding). Over time, societies that have to cooperate intensely become more interdependent, whereas societies that do not have to depend on each other as much become more individualistic. Previous studies have tended to focus on farming versus herding rather than differences between types of farming.

The two major differences between farming rice and wheat are irrigation and labour. Rice paddies require the construction and maintenance of elaborate irrigation systems, in turn requiring cooperation between farmers – often at village level. Farmers also need to coordinate their use of water so as not to adversely affect the supplies of their neighbours. Overall, growing paddy rice is at least twice as labour intensive as wheat farming.

The rice theory predicts that a Unus pro omnibus, omnes pro uno mentality will apply to anybody living in a region where rice has been farmed for thousands of years, not just those directly involved with its production. This prediction was borne out by the study, as few if any of the participants had actually farmed rice or wheat for a living.

My feelings are that while this is an interesting study, one should always be cautious about cultural determinism.

References:

1. Talhelm, T. et al., Large-Scale Psychological Differences Within China Explained by Rice Versus Wheat Agriculture. Science 344, 603-608 (2014).

Link:
http://www.sciencemag.org/content/344/6184/603

Study traces origins of Neolithic in South Asia

Eastward dispersal from Southwest Asia was slower than that unto Europe

A new study, published in the open-access journal PLoS One, has considered the eastwards spread of agriculture from Southwest Asia. This has been less well studied than the westwards expansion into Anatolia and Europe.

Researchers conducted a statistical analysis of radiocarbon dates for 160 Neolithic sites in western and southern Asia. The locations of these sites suggest that the dispersal of farmers eastwards from the Zagros followed two routes: a northern route via northern Iran, southern Central Asia and Afghanistan, and a southern route via Fars through the interior of southern Iran.

Analysis of the radiocarbon dates indicated an eastwards expansion at an average speed of 0.65 km per year, rather slower than the 1 km per year documented for Europe. The authors of report considered this to be unsurprising. Firstly, the arid climate and complicated topography of the region are less favourable for agriculture. Because of this, the early Neolithic settlements in Iran were relatively small and widely separated. Secondly, the European expansion was aided by the Danube, the Rhine and the Mediterranean coastline, but there are no major rivers in Afghanistan or Iran that could play a similar role.

The authors were encouraged that the fairly simple ‘wave of advance’ model used captured the salient features of the data studied, but stressed the need for a more detailed analysis that would consider local environments and climatic conditions.

References:

1. Gangal, K., Sarson, G. & Shukurov, A., The Near-Eastern Roots of the Neolithic in South Asia. PLoS One 19 (5), e95714 (2014).

Link:

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0095714

Bronze Age pastoralists played key role in spread of crops in Central Asia

New archaeobotanical data highlights cereal cultivation by mobile groups during period 2800 to 1200 BC.

Mobile pastoralism first appeared on the steppes of Central Asia during the fourth millennium BC, and was established by the early part of the third millennium BC. Nomadic groups were also responsible for introducing copper, tin, ceramics and bronze metallurgy into the Inner Asian Mountain Corridor between the Altai and Pamir mountain ranges.

However, much less is known of the Central Asian herders’ use of domesticated cereals and the integration of farming into their mobile economies. Botanical evidence for farming on the steppes and mountains of Central Asia has not been previously documented prior to 800 BC, leading to the traditional view that there was a sharp division between nomadic pastors and sedentary farmers in Eurasia and elsewhere.

This view has now been challenged by newly-published archaeobotanical data from four Bronze Age sites in the region. The highland steppe sites of Tasbas and Begash in eastern Kazakhstan, and Ojakly and the unnamed site of 1211/1219 in the Murgab Delta region of Turkmenistan are all believed to have been used as seasonal camps by mobile pastoralists as part of their annual round. Features of these sites include semi-subterranean houses and storage areas.

At Tasbas, wheat and unidentifiable cereal grains were recovered from a funerary urn dating from between 2840 to 2500 BC; and wheat, barley and broomcorn millet dating from between 2450 to 2100 BC were found at Begash. This is the earliest evidence for the use of domestic crops in the region. By 1450 – 1250 BC, cereals were present in far greater quantities at Tasbas: barley, wheat, broomcorn millet and foxtail millet, together with peas. The high density of seeds found in soil suggests that the crops were cultivated locally and not obtained by trading with farmers. Barley chaff used as binder in mud bricks also suggests local cultivation.

The two sites in Turkmenistan date to between 1700 and 1500 BC and have yielded broomcorn millet, barley and wheat. By this time, sedentary farming communities had emerged in the region, and both sites lay close to specialised farming villages. It is likely that the pastoralists obtained their barley and wheat from these, but the farmers did not grow broomcorn millet. Thus it appears likely that the mobile pastoralists were responsible for introducing this crop into the region.

In conclusion, the wheat and broomcorn millet at the two Kazakh sites is earliest evidence for spread of crops into the region – wheat from southern Central Asia and broomcorn millet from East Asia. The seasonal migrations of the pastoralists who used these sites resulted in extensive interactions between local communities throughout the mountainous regions of Central Asia. These interactions resulted in the spread in both directions of crops and agriculture between China and Central Asia among sedentary and mobile groups by the second millennium BC.

The findings indicate that domesticated crops reached Central Asia 2,000 years earlier than previously believed, and highlight the key role of mobile pastoralists in transmitting crop repertoires and transforming agricultural economies in the region. They break down the sharp divide previously thought to exist between nomads and farmers in prehistoric Central Asia.

Reference:
Spengler, R. et al., Early agriculture and crop transmission among Bronze Age mobile pastoralists of Central Eurasia. Proceedings of the Royal Society B 291 (1783) (2014).

 

 

Study provides insight into diet of early Pacific colonists

Lapita people relied on foraging as well as agriculture; men enjoyed a more varied diet than women.

Between 1400 and 800 BC, Polynesian colonists associated with the Lapita culture spread out into the Pacific from Island Southeast Asia, eventually settling the islands of central and eastern Melanesia and western Polynesia. The word ‘Lapita’ is a Western mispronunciation of Xapeta’a, the native Kanak name for the site in New Caledonia that gave its name to the culture. The Lapita culture is noted for its distinctive pottery, which was typically red-slipped, and decorated with small-toothed (‘dentate’) bone or shell chisels.

By around 1300 to 1200 BC, Early Lapita communities were established over a wide area of the Bismarck Archipelago. The dispersed communities formed a network of societies that maintained regular contact with one another, and were probably related by kinship and marriage. The clearest evidence for these long-distance interactions is the trade in obsidian from New Britain and the Admiralty Islands, and parallel changes in pottery styles over the region up until around 1000 BC. After that time, inter-island contacts seem to have dropped off markedly. In the meantime, by around 1200 to 1100 BC, Lapita people had moved beyond the Bismarck Archipelago and settled parts of Remote Oceania. In just 600 years, the Lapita people spread through Melanesia to the Central Pacific, reaching Vanuatu by 1000 BC, Fiji and Tonga by 900 BC, and Samoa by 700 BC. It was here that the migration paused after covering some 5,500 km (3,400 miles), one of the fastest movements of a prehistoric colonising population on record.

The Lapita colonists brought with them domesticated pigs, chickens and dogs, and crops including yams, taro, breadfruit, coconut, sago and bananas. However, the extent to which they relied upon this ‘agricultural package’ for sustenance remains uncertain, and in particular there are questions about how settlers sustained themselves during the initial stages of colonisation of each island.

A powerful technique for understanding the diets of prehistoric peoples is stable isotope analysis. The ratios in which isotopes of certain elements occur in human remains are dependent on what individuals ate while they were alive. Investigations have focussed on stable (i.e. non-radioactive) isotopes of carbon and nitrogen and, more recently, sulphur.

In the case of the Lapita people such investigations have been hampered by a scarcity of human remains, despite around 250 sites being known throughout the western Pacific. However, a cemetery at the site of Teouma, on Efate Island, Vanuatu has yielded 68 burials – the largest number of human remains from the Lapita period ever found. The cemetery dates to the earliest known settlement of Central Vanuatu, around 1000 BC. As such, it can provide information about the settlers’ diet during the initial stages of Lapita colonisation.

The researchers obtained isotopic ratios for bone collagen from 51 adult Lapita people. They then obtained a comprehensive isotopic dietary baseline made up of both modern plants and animals, and prehistoric animal remains from the site. By comparing the two sets of results, they found that the settlers’ diet included reef fish, marine turtles, and fruit bats in addition to domesticated pigs and chickens. Rather than rely solely on their ‘transported landscape’ of domesticated crops and animals, the settlers were practicing a mixed subsistence that included significant quantities of native wildlife, as well as domestic animals.

Dietary differences were found between men and women. The men enjoyed a more varied diet, which included greater access to pigs, chicken and tortoises. Such foods are considered to be of high status in present-day Pacific island societies, and the difference may reflect a higher status for men in Lapita society.

The results are consistent with the view that a newly-established colony would not be able to produce enough food to support itself, and would have to rely to an extent on foraging. This is also supported by an analysis of the remains of domestic pigs and chickens, which suggested that they were reared as free range animals. Such a system of husbandry would reduce demand for the limited amount of plant food that was available.

Reference:
1. Kinaston, R. et al., Lapita Diet in Remote Oceania: New Stable Isotope Evidence from the 3000-Year-Old Teouma Site, Efate Island, Vanuatu. PLoS One 9 (3), e90376 (2014).