of blood. The Pashtuns are largely connected to the culture of Central Asia and the Iranian Plateau. The remaining Afghans are culturally Persian and Turkic. Some non-Pashtuns who live in proximity with Pashtuns have adopted Pashtunwali in a process called Pashtunization, while some Pashtuns have been Persianized. Those who have lived in Pakistan and Iran over the last 30 years have been further influenced by the cultures of those neighboring nations. The Afghan people are known to be strongly religious. Afghans, particularly Pashtuns, are noted for their tribal solidarity and high regard for personal honor. One writer considers the tribal system to be the best way of organizing large groups of people in a country that is geographically difficult, and in a society that, from a materialistic point of view, has an uncomplicated lifestyle. There are various Afghan tribes, and an estimated 2–3 million nomads. Afghan culture is deeply Islamic, but pre-Islamic practices persist. One example is bacha bazi, a term for activities involving sexual relations between older men and younger adolescent men, or boys. Child marriage is prevalent in Afghanistan; the legal age for marriage is 16. The most preferred marriage in Afghan society is to one's parallel cousin, and the groom is often expected to pay a bride price. In the villages, families typically occupy mudbrick houses, or compounds with mudbrick or stone walled houses. Villages typically have a headman (malik), a master for water distribution (mirab) and a religious teacher (mullah). Men would typically work on the fields, joined by women during harvest. About 15% of the population are nomadic, locally called kochis. When nomads pass villages they often buy supplies such as tea, wheat and kerosene from the villagers; villagers buy wool and milk from the nomads. Afghan clothing for both men and women typically consists of various forms of shalwar kameez, especially perahan tunban and khet partug. Women would normally wear a chador for head covering; some women, typically from highly conservative communities, wear the burqa, a full body covering. These were worn by some women of the Pashtun community well before Islam came to the region, but the Taliban enforced this dress on women when they were in power. Another popular dress is the chapan which acts as a coat. The karakul is a hat made from the fur of a specific regional breed of sheep. It was favored by former kings of Afghanistan