Pigeons played a central role some 1,500 years ago in transforming the Byzantine Negev into a flourishing garden, according to a new study conducted at the Zinman Institute of Archeology at the University of Haifa and published Wednesday in the journal PlosOne.
The study, which focused on the ancient settlements of Shivta and Sa’adon, found archaeological evidence that the Byzantines in the Negev did not raise their pigeons for food, but to fertilize the dry loess soil and making it more suitable for intensive agriculture.
Loess is made up of fragment of geological detritus, formed by the accumulation of wind-blown dust. But despite its lowly origins, loess tends to develop into very rich soils. Under appropriate climatic conditions, it forms some of the most agriculturally productive terrain in the world.
“The pigeon droppings are rich in phosphorus, potassium and nitrogen, which are essential for agriculture and lacking in the loess soil of the Negev,” the researchers noted, adding that “the fact that the pigeon bones we found are much smaller than pigeons grown for meat, along with the nesting materials discovered in the trenches and the location of these within the agricultural fields, indicate that the pigeons were grown without significant human intervention, with people mainly providing them with protection.”
In recent years, a large-scale study has been conducted in the Byzantine Negev communities, led by Prof. Guy Bar-Oz of the University of Haifa, in an attempt to understand, among other things, how the Byzantines managed to maintain an extensive farming system in the desert about 1,500 years ago, and what caused these thriving communities to be abandoned overnight.
In a study published several months ago, the research group presented significant archaeological evidence of the extent of agriculture in the Negev at the time, using the bones of a rodent (Marion), which lives only in more humid environments and is not found in desert.
Now, Dr. Nimrod Marom of the University of Haifa and Tel Hai College, together with Prof. Bar-Oz and Dr. Yotam Tepper of the Institute of Archeology at the University of Haifa and Dr. Baruch Rosen of the Volcani Institute, are focusing on the study of the bones of pigeons found in coops in the agricultural areas near the Byzantine settlements.
According to the researchers, pigeon droppings are renowned to be a source of important minerals for agriculture, such as phosphorus, potassium and nitrogen, and in many areas of the world it was customary until recently to use them to improve and fertilize the soil. However, throughout history, pigeons have also been raised for meat. In order to determine main use of the pigeons in the Negev Byzantine colonies, the researchers examined the pigeon bones found in the coops, as well as the chemical composition of the droppings themselves.
The large amount of bones found in the excavations allowed the researchers to identify the average length of the wing, the body structure, and the characteristics of the skull of the pigeons from the Byzantine period, compared to the bones of pigeons of different races from modern times.
The work was based, among other things, on comparing the pigeons from the Negev to the pigeons collected and classified by the father of evolutionary theory Charles Darwin himself. Their bones are stored in the British Museum.
The researchers’ most important discovery was that the pigeons from the Byzantine period were small, muscular and “athletic,” and no different in size from Darwin’s wild pigeons. According to Dr. Marom, a smaller body size is not only a clear indication of the pigeons in question having less meat on their bones, but that they also had a faster metabolism. Simply put: smaller ions produce more guano relative to the food they consume.
The chemical tests conducted in the laboratory showed that the droppings are indeed rich in nitrogen, phosphorus and potassium.
“In addition to this fact, the coops’ location, in an agricultural area and away from the settlements, strengthens the hypothesis that the pigeons were grown in the coops to produce high quality manure intended to improve the loess soil of the desert,” the researchers concluded.
“The pigeons from Shivta could fly freely and get their food themselves, the guano that was collected on the floor of the coops was used to fertilize fruit trees and vines in the local vineyards and orchards. In addition, we discovered inside the coops a rich botanical finding that included vines, dates, olives, peaches and a variety of wild plants, all scraps of food the pigeons ate,” they added, suggesting “this is additional evidence that the Negev in the Byzantine period was green and blooming.”