Final answer:
H. erectus experienced slower brain growth after birth compared to modern humans, correlating with behavioral and physiological changes that supported a more advanced lifestyle.
Step-by-step explanation:
H. erectus brain growth after birth was less rapid than in modern humans. Throughout its evolutionary history, H. erectus showed a progressive increase in brain size, indicative of a pattern of encephalization. Evidence from fossil records suggests that H. erectus brain size ranged from approximately 550 cc to as high as 1,250 cc, a size that aligns more closely with that of later hominins and Homo sapiens. This increase in brain size is related to several behavioral and physiological changes including the increased use of fire, consumption of cooked meat which is softer and requires less chewing, thus smaller teeth and jaws, and a more nutrient-rich diet. The cranial capacity of H. erectus also correlates with their enhanced cognitive abilities and the development of their tool-using skills. These evolutionary changes provided H. erectus with a greater capacity for long distance running and adaptation to various climates, aiding in their ability to migrate out of Africa and into other continents.