Read Paragraph 11 from the passage. With the development of agriculture, the human
population grew, thriving on plentiful harvests of
wheat and barley. But the area around the grain
fields was not good for wild animals. When
people cleared a piece of land, the gazelles, red
deer, wild boar, and goats that once roamed
there lost much of their natural food supply, and
so they moved on. As time passed, hunters
found fewer and fewer animals to hunt. Hunting
had always required great skill. Now hunters
needed even greater skill if they wanted to eat
meat.
How does the phrase "natural food supply"
affect the passage?