Answer:
The answer is actually: "Domesticated animals grazed on grass clearing areas for crops."
Explanation:
At first it may sound weird, but it is actually the answer.
Back when animals became domesticated, the first species to become them (domestic/domesticated) were the cows.
Around this time of age, agriculture had changed as the society and civilians living back then found a way to live in one area, and not have to hunt and gather anymore. But the cause of change in that era was not due to the domestic creatures. But idea that they could grow crops, and other foods in a(n) area instead of having to go around hunting-gathering.
When the civilians back in that age need to grow crops, they would send their cows in order to eat the grass to form land to clear of any weeds or plants in the area. Then they would dispense seeds and grow what they needed.
