The Rise of Civilizations
Specialization of Labour
For thousands of years mankind survived by doing whatever they could to find food and shelter for themselves and their families. A clan of individuals had to do all the tasks necessary for life, including hunting, dressing kills, gathering, making tools, and making shelters. As societies became larger and more complex, individuals began to specialize in different types of jobs. It was no longer necessary for one individual to learn how to do every kind of work.
Written language began as pictures known as glyphs. These glyphs represented objects and ideas. Over many thousands of years these glyphs have evolved becoming the letters that we use today.
As civilizations grew, becoming more advanced, the demand for certain products, such as copper and tin increased. People began to desire products that were not available in their own lands, such as exotic spices, grains, animals, and so forth.