Three women dressed in black abayas and shielded from the hot desert sun in wide-brimmed straw hats called nakhls, and even gloves, tend goats near Shibam, on the edge of the Arabian Peninsula's Rub al Khali, or Empty Quarter. (From the book What I Eat: Around the World in 80 Diets) This section of the Arabian Desert holds the world's largest stretch of sand. Further north into Saudi Arabia, this desert contains some of the world's richest oil and gas fields. Though modestly dressed, the women aren't adverse to throwing stones to keep their goats close by?or to keep strangers with cameras away.