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...