In nomadic times, cultures marked the passage of time with the migration of the herds. as people developed agriculture, a more precise measurement of time became increasingly important. farmers needed to time the planting and harvesting of crops just right, or they would not have enough food for the winter. keeping track of these natural cycles was so important that the dates were coordinated with religious ceremonies at the core of society. with the development of agriculture came food surpluses, which led to more complex forms of government and the ability to trade with other cultures. record keeping grew, and historians and rulers needed a way to track when certain events occurred. merchants needed a way to know when deliveries were due or payments needed to be made. military leaders needed to be able to coordinate attacks and defenses. the accurate recording and interpretation of time was central to the development of civilization. what is the main idea of this passage?