Final answer:
Homo erectus' larger brain and physical adaptations allowed them to hunt large animals, improve their diet, and expand into colder climates.
Step-by-step explanation:
Homo erectus may have played an important role in hunting large animals, improving their diet, and expanding into colder climates. The development of a larger brain with highly developed cognitive skills allowed Homo erectus to solve problems and create tools for better hunting and survival. Additionally, adaptations such as the ability to walk and run longer distances and explore new territories enabled Homo erectus to track and follow game and expand their range.