Bar-Ilan University researchers have found a cache of 120,000 wild oat and 260,000 wild barley grains at the Gilgal archaeological site near Jericho that date back 11,000 years - providing evidence of cultivation during the Neolithic Period.
The research, performed by Drs. Ehud Weiss and Anat Hartmann of BIU's department of Land of Israel studies and Prof. Mordechai Kislev of the faculty of life sciences, appears in the June 16 edition of the prestigious journal Science.
It is the second time in two weeks that Kislev and Hartmann have had an article in Science. They recently wrote about their discovery of 10,000-year-old cultivated figs at the same Jordan Valley site.
According to the researchers, the newest find shows that the transition from nomadic food gathering and the beginning of agriculture were quite different than previously thought. Until now, the general assumption has been that agriculture was begun by a single line of human efforts in one specific area. But the BIU researchers found a much more complicated effort undertaken by different human populations in different regions, drawing a completely new picture of the origins of agriculture.
Agriculture, the BIU researchers suggest, originated through human manipulations of wild plants - sometimes involving the same species - that took place in various spatially and temporally distinct communities. Moreover, some of these occasions were found to be much earlier than previously thought possible.
The researchers analyzed archeo-botanical data from Near Eastern archeological sites to locate human attempts to grow early crops. Several plant species, which they term "pioneer crops," were found to be the earliest plants manipulated by humans. Some of these attempts succeeded, which means that domestication and continuity were achieved, while others were abandoned. They offer a model of a pioneer agriculture with its disappointments and achievements.
They were certain that the grains found at Gilgal were cultivated and not found naturally in the environment because they were found in such large quantities and because field observations showed that only moderate amounts could be gathered from natural growing sites in this part of the Jordan Valley, even in rainy years.
Although pioneer crops such as barley, lentils, rye and oats yielded satisfactory crops, early farmers faced the problem that their seeds would fall off immediately after ripening. One way to solve this problem was through domestication (causing a process by which plants would retain their seeds, rather than shedding them, to facilitate collection by farmers).
But the researchers found that not all crops were easily domesticated, causing our ancestors, the researchers maintain, to abandon certain crops (such as oats) for thousands of years, until different farmers in other parts of the world finally domesticated them.
This new hypothesis turns the spotlight on the peoples who were involved in creating a revolutionary new agricultural way of life. According to the researchers, it was not a particular individual or community who changed the way we live our lives today, but rather many human groups scattered throughout the world who manipulated several different local wild plants. Some of these groups failed in their attempts and some succeeded. Some plants were domesticated and some were abandoned.
Moreover, some of the plants abandoned during the Neolithic Period were later domesticated in other parts of the world. Barley and, most likely, oats, were cultivated in the Jordan Valley, represented by the early Neolithic site Gilgal.
However, domesticated oats appeared some seven thousand years later in Europe, several thousand kilometers away. Another domesticated plant - rye - was found to be cultivated by several Turkish communities, from the Neolithic Period onward, for several millennia. Some of these communities even succeeded in domesticating rye, but they apparently abandoned it. Rye apparently traveled from Turkey to Europe in the form of a weed that grew in fields of barley and wheat. As in the case of oats, the last stage of rye domestication occurred not in Turkey but in Europe, and several thousands of years later.
The wild lentil plant's path of domestication comprised two stages: loss of dormancy (most of the seeds do not germinate in the first year) and development of pod indehiscence (pods that do not spontaneously release their seeds). The researchers noted that the first evidence of lentil domestication - loss of dormancy - was found in the beginning of the Neolithic Period in Jerf el-Ahmar, Syria, and quickly spread south to Netiv Hagdud in the Jordan Valley.
Undoubtedly, the final stage of lentil domestication is represented by the huge, approximately 1.4 million lentil seed hoard found in later Neolithic Period Yiftah'el, near Nazareth, some 600 kilometers southwest of Jerf el-Ahmar.
According to the researchers, a similar phenomenon occurred in North America, where the chenopod, marsh elder, squash and sunflower became domesticated under indigenous group management between 4,000 and 5,000 years ago. The erect knotweed, little barley and maygrass were cultivated and later abandoned, eventually to be replace by maize-centered agriculture and the arrival of the common bean.