Answer:
Fire was very important for early man.
Step-by-step explanation:
Stone tools did exist before the beginning of controlled fire. But in Stone Age, man combined the two technologies. It was discovered that heating rocks around a fire brought out impurities, which made the rocks easier to cut into stone tools.
Fire became a source of warmth and protection. It was easier for man to stay in low temperatures and geographic expansion could be possible. There was improvement in hunting and there was a method to cook food. With these cultural advances man could expand geographically, there could be cultural innovations, diet and behavior could change.