The main and immediate change that agriculture brought the sedentary. Groups had to look after their plantations, harvest them and store the products that they did not immediately consume; therefore, they could no longer travel to different places.The second big change was in housing: branch sheds and caves were not enough, as in nomadic life.They had to build the first houses, with whatever was available in the area: stone, mixed wood,etc. The gathering of several houses, often behind a fence to protect themselves from predators and enemies, led to the formation of hamlets and villages.The populations mastered the cultivation techniques: fertilizer, irrigation, seed selection and conservation of the surpluses, as well as the breeds of domesticated animals and the quality of the tools used. This increased the harvested product, which was the third big change.The availability of more consumable calories brought the increase in population, the fourth big change. Biologists have estimated that the total world human population, 10,000 years ago, was between 5 and 10 million. After 8,000 years, this figure had become 300 million.