Final answer:
Homo erectus individuals most likely got the majority of their daily calories from meat, which was made possible by evolutionary changes like increased brain size, the use of fire for cooking, and physiological adaptations for hunting.
Step-by-step explanation:
Homo erectus individuals were most likely consuming most of their daily calories from meat. This dietary shift was facilitated by several key evolutionary adaptations:
- Their increased brain size necessitated a higher caloric intake. Smaller teeth and jaws are indicative of a transition from tougher plant-based food to softer, higher-calorie diets, including meat.
- The use of fire for cooking meat resulted in a more calorie-rich diet and is evident at H. erectus sites.
- Evidence from fossil remains, such as KNM ER 1808, suggests an increase in meat consumption, possibly including high Vitamin A sources like carnivore liver.
- H. erectus's taller stature and longer legs were an advantage for hunting and foraging, thus supporting a diet that could include a significant amount of meat.
Moreover, cultural and technological advancements such as tool use and cooperative hunting likely contributed to their ability to obtain and process meat more effectively. Conclusively, while their diet also included nuts, fruits, berries, and other plant materials, meat was a significant source of daily caloric intake for H. erectus.