We hunted and gathered for our food in the paleolithic era.
We had larger Populations in the Neolithic era.
We discovered farming in the neolithic period.
The first civilization was Sumer, developed around 3500 BCE
During the old stone age people used stone tools, and hunted and gathered for their food.Because they did not have a lot of food they lived a nomadic lifestyle. Groups were usually no bigger than 60 people.
The New stone Age began around 9000 BCE when people learned to farm. People also domesticated some of the animals we use today in the New stone Age. People started to live in one place. Agriculture created a steady supply of food causing population growth. Farming villages started coming up, some of them turned into cities.
Some areas of the world developed a civilization. These places had changes like writing, job specialization, government and technological improvements.