Quechua people Quinine, which is found naturally in bark of cinchona tree, is known to be used by Quechuas people for malaria-like symptoms. When chewed, coca acts as a mild stimulant and suppresses hunger, thirst, pain, and fatigue; it is also used to alleviate altitude sickness. Coca leaves are the raw material from which cocaine, one of Peru's most historically important exports, is chemically extracted. Many indigenous women wear the colorful traditional costume, complete with bowler style hat. The hat has been worn by Quechua and Aymara women since the 1920s, when it was brought to the country by British railway workers.
Bark pocket indicator of air pollutants during which the time they formed. They can be used to monitor heavy metals such as lead and copper, as dust or other matter deposited on the bark at the time of formation is still present. One study analysed the amount of polycyclic aromatic hydrocarbons (PAHs) present in bark pockets as a historical record of air quality, possible due to the interaction between PAHs and lipids in the bark. Bark pocket Bark pockets can be formed by inosculation, formation of a tree fork, encapsulation of a branch, joining together of an uneven trunk, or encapsulation of