During the Neolithic era, the Earth had a warmer climate than it had in the previous era, which allowed Neolithic people to keep domesticated animals for food and to eat food that they farmed. They farmed vegetables such as wheat, barley and lentils.
During the Neolithic era, people started to give up their nomadic lifestyles and build communities. They domesticated cattle, goats and pigs as food sources. Both farmers and shepherds were able to focus on one crop or animal, and they traded with other members of their community for whatever else they needed. Neolithic people in Southwest Asia were the first to domesticate plants, including oats, peas, lettuce and carrots. These are known as Neolithic founder crops, and they spread around the world from the Fertile Crescent.