Once, in ancient times, the Middle East teemed with carts and wagons and chariots, but they were totally driven out by the coming of the camel:
Good harnesses for camels were designed in Central Asia and, in the 19th century, in the Australian desert, but these did not affect the Middle East.
The only way to make use of this immensely strong beast for transport was to throw the load, averaging anywhere from 300 to 500 pounds, on its back. Thus the pack camel came to compete directly with the ox cart for heavy transport.
The ox cart was equally slow, and in the competition the camel had certain positive advantages. It ate otherwise unusable desert plants, which made its upkeep inexpensive. Little wood, a valuable commodity in the largely deforested Middle East, was required by ancient saddling technology. And its care and breeding could be left to the nomads and thus not be a burden upon the farmer or merchant.
These advantages meant that camel transport was about 20 percent cheaper than wagon transport, according to the edict on prices issued by the Roman emperor Diocletian in the third century A.D. Therefore, simple economic efficiency caused the camel to supplant the wheel, not some mysterious reversion to primitive life.
(Hat tip to commenter Harold!)
Other results of the conversion to camels was the loss of paved roads, which gradually deteriorated into tracks, and increased desertification. The Arabs’ goat completed the destruction of North African farming.