Major changes in the climate of the world with a shift to relatively warm conditions were noticed around 12,000 years ago. As a result, grasslands developed in many regions. This resulted in the increase in the herbivorous animals like deer, antelope, goat, sheep and cattle. This encouraged people to herd and rear these animals. They also engaged themselves in fishing.

Several grain bearing grasses such as wheat, barley and rice also grew around this time in different parts of the sub-continent. Men, women and children began to collect these grains to use them as their food. By the time, they also learnt where these grains grew and when they ripened.