For thousands of years, different groups of people have lived in the Negev desert, building stone walls and cities that survive to this day. The current thinking is that they raised animals, and didn't practice agriculture before about the first century, but Hendrik Bruins, a landscape archaeologist at Ben-Gurion University of the Negev, in Israel, says that his research suggests people in the Negev highlands practiced agriculture as long ago as 5000 BCE.
     Bruins' as yet unpublished findings come from dating of bones and organic materials in various layers of an ancient field in southern Israel. He found evidence of past cultivation, including animal manure and charred organic material (likely burnt kitchen scraps), both of which have been used as fertiliser around the world for millennia.
     He found three distinct layers in the earth corresponding to three different periods of activity, indicating that the field had been cultivated, with long gaps in between. The first dated from 5000 BCE to 4500 BCE, followed by another from 1600 BCE to 950 BCE, and a final layer from CE 650 to CE 950.
     The first group that farmed here around 7000 years ago has no currently known name, he said, but developed flint tools that have been found throughout the region.
     The second period, from 1600 BCE to 950 BCE, corresponds to the time in which the Jews made their way from Egypt to modern-day Israel, according to Exodus and other books of the Bible. Bruins says the site, south of Beersheba, is likely to the south and east of where historians place the Israelites during this time period, but could possibly have been home to tribes associated with the Amalekites, a group living in the area at the time that was hostile to the Israelites.
     According to Bruins, these desert peoples used walls and ditches to collect rainwater during the area's infrequent rainfalls. Later inhabitants of the area, known as the Nabataeans, were skilled at collecting and conserving rainwater, allowing them to establish and run a thriving trade route through the area before the arrival of the Romans.
     The third layer corresponds to the late Byzantine and early Islamic period, when people were known to practice agriculture in this area.
     Graeme Barker, a researcher at the University of Cambridge, says that if the study does prove that agriculture has been practiced in the area since 5000 BCE, that finding would be "great, and important."

Edited from LiveScience, Yahoo! News (19 March 2013)