The difference is debated upon among anthropologists, many believe the ergaster to differ only based on geological placement; ergaster is usually found in Africa.
The homo ergaster had a smaller cranial base, a larger nose bones and openings,than erectus. The jaw was also different,with smaller lower canines. The optical bone was also larger, making the eyebrow area more prominent.
The ergaster and erectus species are both interchangeable. They lived on hunting. There difference are physcial and only from the remains of the skull we will know it.
Theere's some disagreement on the topic between experts in the field. Some experts claim that Homo ergaster gave rise to Homo erectus, while others deny that ergaster is a separate species at all. The first group suggests that homo ergaster preceded the erectus, and that they differed in brain capacity.
