Briefly describe the three stages of agricultural development. What are their characteristics?

The characteristics of primitive agriculture: relying on the sky to eat! Slash-and-burn, land, fertilizer and irrigation almost depend on the weather for food. The number of poultry and livestock raised has decreased. The characteristics of traditional agriculture: fighting against heaven and earth! Simple agricultural tools and machinery are used for digging wells, repairing canals and irrigation, artificial fertilization, leveling land and building terraces, and sowing cash crops. Mass reproduction of poultry and livestock. Characteristics of modern agriculture: man can conquer nature! Modern agricultural machinery, artificial breeding, modern water conservancy facilities (drip irrigation, sprinkler irrigation), greenhouses and soilless culture are widely used. Hybrid crops and transgenic crops are planted in a large area, which significantly enhances their ability to resist natural disasters, greatly improves crop yields, develops agricultural extension industries, popularizes secondary processing, and intensifies, scales and marketizes animal husbandry.