Wheat was present in Britain 8, years ago, according to new archaeological evidence. Fragments of wheat DNA recovered from an ancient peat bog suggests the grain was traded or exchanged long before it was grown by the first British farmers. The research, published in Science , suggests there was a sophisticated network of cultural links across Europe. The grain was found at what is now a submerged cliff off the Isle of Wight.
Farming of plants and animals first appeared in the Near East, with the technology spreading along two main routes into Europe. The accepted date of arrival on the British mainland is around 6, years ago, as ancient hunter gatherers began to grow crops such as wheat and barley.
The DNA of the wheat - known as einkorn - was collected from sediment that was once a peat bog next to a river. The distribution of wheat outside of its place of origin is part of the process known as "Neolithicization. Further tests at Bouldnor Cliff have identified a submerged Mesolithic site, 16 m 52 ft below sea level. The sediments were laid down about 8, years ago, several centuries earlier than the European LBK sites. Scholars suggest that the wheat got to Britain by boat.
Other scholars have questioned the date, and the aDNA identification, saying it was in too good a condition to be that old. But additional experiments run by British evolutionary geneticist Robin Allaby and preliminarily reported in Watson have shown that ancient DNA from undersea sediments is more pristine than that from other contexts. Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile.
Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Share Flipboard Email. Kris Hirst. Archaeology Expert. Kris Hirst is an archaeologist with 30 years of field experience. Her work has appeared in scholarly publications such as Archaeology Online and Science. One should always be a bit cautious in suggesting far-reaching conclusions on the basis of a few seeds recovered from one or more cubic meters of deposit In these early periods, it seems that pounding stones were put to multiple use, and aside from grain processing were utilized for crushing various edible wild plants and even pigments.
Only later, or in occasional localities with abundant edible grasses, did the number of tools, exclusively intended for grains, increase.
There is evidence that the second phase of the agricultural revolution, the domestication revolution, begins with the selection of domesticated races of wheat and barley in Prepottery Neolithic A PPNA from to B. The earliest evi-. The invention of fields by Neolithic peoples of the Near East may have been inspired by their observation of indigenous natural grasslands of annuals such as wild emmer and barley occurring in open forest belts of deciduous oak.
Man may have burned off unwanted grass in the open forest and used the cleared space for sowing grain. Later, he expanded agriculture to adjacent regions, possibly by using marshland areas as primitive irrigated or moist fields 13 or by clearing dense woods of evergreen, sclerophyllous low trees and shrubs. Transformation of the landscape from high perennial evergreen vegetation to fields with annual winter grasses was one of the first important man-initiated changes in world vegetation.
No doubt, this modification drastically affected the equilibrium of indigenous wild life in these marshes and forests. Although wild einkorn and wild barley were found at Tell Mureybit, N. Syria, and dated between and B. The ripe ear of domesticated emmer no longer fractures as easily as that of the wild species, and it could be gathered without loss of the ripe upper spikelets. The chaff and rachis nodes of domesticated emmer may also have been less sturdy and its awn shorter, thinner and with smaller teeth than its progenitor.
Only at that stage of domestication could sheaves be bound and stacked without severe loss of yield. Threshing should also have been practiced at that time. The most characteristic feature of domesticated cereals is that they must be sown by man and can no longer disperse their seeds unassisted. Therefore, man's selection and raising of domesticated wheat, particularly emmer, which lacks spontaneous shedding of the grain, even at maturity, could only have occurred after ploughing and sowing were practiced.
The whole ear, connected to its culm, cannot hide its grains in the ground like a single spikelet does, thus preventing germination. It seems that at the end of the PPNA all essential agriculture practices had already been established.
One particularly relevant question relating to cereal domestication is : Why did the chance mutation producing a nonshattering ear i. One popular explanation offered is that when man began planting his harvested emmer and barley, selective pressures were automatically created.
As long as human activity was confined to gathering wild plants, it was the seeds which escaped. Once man started to plant what he had harvested, the situation changed drastically.
The seeds that were harvested were those that contributed to the next year's population, and the modification producing a nonshattering ear would be favored However, this explanation has some difficulties, namely, that this mechanism of selection would be effective only if new fields are planted from year to year.
If, however, the same field were harvested and sowed, a most likely possibility, then, harvested grains and escaped ones would combine in the next generation, producing a composition not very different from that of the previous year. It therefore seems that selective pressure was exerted at a different stage of food processing.
Apparently, mutations producing nonshattering ears had already appeared in the wild emmer populations of the PPNA. A scenario may be drawn that in this period, both whole ears and separate spikelets were gathered and stored for consumption and sowing. When taking part of the annual store for braying in the narrow mortar, the woman undoubtedly preferred the separate spikelets, saving her the work of threshing the whole ear, to individual spikelets.
As a result, it was these less fragile whole ears that were left over at the beginning of winter for sowing. In following years, it was much easier to harvest the nonshattering ears, but more work was than required to prepare food. In short, by trying to avoid extra work, PPNA women unconciously selected nonshattering emmer and barley ears, which while making subsequent harvests much more convenient, introduced the necessity for breaking the rachis.
This evolutionary stage might have taken longer if more than one gene were responsible for nonshattering. The next step in domestication was denudation of the grain, producing grains that separate more easily from the chaff than do hulled cereals. The first record of naked more likely tetraploid than hexa- ploid wheat comes from Tell Aswad, phase II, dated B.
We do not yet know whether naked wheat was grown then as an admixture in emmer fields or as a separate field crop. The fact that both hulled wheat and naked wheat are found contemporaneously for over 7 millennia may indicate that the overall advantage of the latter was not great enough to displace the former as a major crop. The third phase, the expansion of agriculture, was actually a rapid and radical change of economic organization, as hunters and gatherers in permanent settlements became farmers.
Cereal culture expanded from the Fertile Crescent to central Asia through N. Iran, and westward to Europe through S. Anatolia fig.
Areas above m are shaded. The first regions cultivated on the Mediterranean peninsulas were always the south-eastern plains adjacent to the coast. Early agriculture in the Balkans has been comparatively well documented and summarized In the 6th millennium B.
Most of the wheats were the hulled, domesticated emmer and einkorn, and only rarely the more advanced naked tetraploid or hexaploid wheats. The need of foreign plants to adapt to climatic conditions in a newly occupied region, and the existence of geological obstacles, such as high mountains, may have tended to slow down expansion, while a period of favorable climate may have tended to accelerate it. During migration of wheat and barley species to the northern Balkans, for example, the sharp contrast between suitable dry summers in the south and unfavourable rainy summers in the new area, required an adaptation period before further advance was possible.
Although fields in the Near East may occur at higher elevations Hacilar m , most of the sites in Europe are located below m, and every reasonable route of. One possible explanation is that ancient Near Eastern wheats could not survive the colder growing seasons and frost of the high mountain elevations in Europe.
Indeed, there is palynological evidence that about B. In central eastern Europe, winters are hard, but summers are relatively warms. As the major growth season of vegetation is in the warmer part of the year, it was relatively easy for wheat to migrate northward into the continent. Moreover, in central Europe, during the Lower Atlantic period, B. Hulled wheats were established first and were the most important cereals; only subsequently did barley appear in large quantities Again, introduction of agriculture radically changed the landscape from deciduous, dense forests to annual grasslands.
The alteration in the rhythm of. It is very difficult today to reconstruct the adaptive changes that the wheat plant had to undergo during migration from the Near East into its new habitats.
However, some clues are available by examination of the typical characteristics of the local crops found today along the route of advance. Vavilov collected thousands of local races from all parts of the world and observed them under different climatic conditions. By analyzing genetic features, he could identify the agro-ecological characters of each region with the aid of an "ecological passport", i.
By assuming that the characteristics of local, naturalized domesticated plants reflect adaptations to the ecological conditions under which they are grown, the changes which the naked, and presumably also the hulled wheat species have undergone by passing from region to region may be reconstructed.
During migration from the Near East via W. Anatolia to the Mediterranean Balkans and then northwards fig. The originally small plant began to grow taller, reaching an even greater height in Europe; its vegetative period lengthened to take advantage of long summer days and a longer rainy season ; leaves, as well as ears and grains, increased in size, and the need for high temperatures for maturation gradually disappeared.
What was the rate of migration of wheat agriculture from the Near East to Europe? This has been estimated at about one km per year Hungary - B. Thus, the rate, during the first years of wheat expansion average 1. In addition to the time a cereal needs to adapt to climate, the speed of expansion of agriculture was.
First, in regions with a rich supply of wild cereal grains, e. This may help explain why in these earlier periods, the speed of agricultural expansion was slower than in subsequent periods. On the other hand, later, near the end of the 7th millennium, the migration from S. Anatolia to S. Greece through the Aegean Sea, was apparently uninhibited most likely because seafaring was then a known tradition It also seems that the spread of agriculture in Europe was faster among people of the same Neolithic culture.
In the Linearbandkeramic period, migration of people northward and westward contributed to the acceleration of agricultural expansion Most likely, not all species spread at the same spreed to temperate Europe. While, emmer along with einkorn, is almost always in the forefront of agricultural expansion, other crops such as barley, flax, peas and lentils were probably only secondary or occasional migrants 33 ; others, however, such as tetraploid naked wheat, grass pea and bitter vetch were nearly totally restricted to the Mediterranean region.
During the early Neolithic Age of central Europe, agriculture was still limited to a few crops, sometimes merely the monoculture of mixed hulled diploid and tetraploid wheats The Neolithic people handed down most wheat species to their descendants, plants which were preserved locally for thousands of years.
At the end of our own millennium, we are witnessing the rapid disappearance of thousands of local wheat types in favour of uniform, high-yielding races that are very susceptible to sudden attack by viral or fungal disease. If the green revolution continues to be associated with this frightening decrease in cultivation of local races, we may have to characterize the next period by the collapse of traditional agriculture. Botanical remains found in archeological excavations, when dated and well identified, provide essential data for understanding the origins and migrations of crops, as well as of weeds.
From recent Neolithic wheat finds in the Middle East and SE Europe, a clear, though fragmentary picture of the development of wheat agriculture has emerged. In , Helbaek identified cultivated hulled wheat emmer and einkorn , and in Hopf found.
The remnants are mostly grains, burned to charcoal. Rachis fragments are also found, sometimes with the highly diagnostic glumes but almost never a whole spikelet or ear. Therefore a new set of diagnostic features was developed for identifying the various species or groups of species.
The sturdy bases of glumes, sometimes together with rachis fragments, fork-shaped and broken clearly at the weak point, are the best characters for identifying contemporary wild and cultivated hulled wheats. The dimensions and the general shape of the grain, e.
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