The core group within this species is believed to have lived in-between 1.5 and 1.9 million years ago. This species was first proposed as a new species in 1975 after a scientist re-examined a jaw previously classified as Homo habilis. These same traits were later found in a group of fossils that had been initially though of as part of the species Homo erectus.
Some of it's key physical features are:
The body is usually considered to be tall and slender with long legs which may have been an adaptation from the hot, dry environment(maximise cooling). Females grew to about 160 centimetres where-as males grew to around 180. The body may have been relatively hairless as a way to help improve body cooling by sweating. The ribcage was more like that of a modern human's along with the changes tot he shoulder, chest and waist. This new body shape improved the body's balance and made it possible to run.
The brain of an average homo ergaster was approximately 860 cubic centimetres and made up about 1.6% of their body weight.
The skull had developed a more human-like shape including a higher, more domed skull and the nose was human-like for the first time. It was now projected outwards.
The jaw was shorter and more lightly built than those of earlier species which resulted in a flatter, shorter face. Like the earlier species, the front of the lower jaw slopped backward and did not form a pointed chin similar to that of a modern human's. The arrangement of the teeth within the jaw were much further apart at the back of the jaw than at the front.
The pelvis was shaped like that of a modern human and was relatively narrow. This most likely allowed more efficient movement on two legs. Their spinal cord was also thinner than those of a modern human. This may have resulted in them having limited speech due to the lack of nerves needed for complex control of breathing whilst speaking.
The limbs were also very different. Unlike earlier species, the legs were now much longer than the arms and their tree climbing adaptations were gone.
The Homo ergaster species were the first to take advantage of the open environment. The development of a smaller gut and a bigger brain suggested that they relied on more nourishing food hence the reason it is believed that their diet included more meat then previous species.
Some of it's key physical features are:
The body is usually considered to be tall and slender with long legs which may have been an adaptation from the hot, dry environment(maximise cooling). Females grew to about 160 centimetres where-as males grew to around 180. The body may have been relatively hairless as a way to help improve body cooling by sweating. The ribcage was more like that of a modern human's along with the changes tot he shoulder, chest and waist. This new body shape improved the body's balance and made it possible to run.
The brain of an average homo ergaster was approximately 860 cubic centimetres and made up about 1.6% of their body weight.
The skull had developed a more human-like shape including a higher, more domed skull and the nose was human-like for the first time. It was now projected outwards.
The jaw was shorter and more lightly built than those of earlier species which resulted in a flatter, shorter face. Like the earlier species, the front of the lower jaw slopped backward and did not form a pointed chin similar to that of a modern human's. The arrangement of the teeth within the jaw were much further apart at the back of the jaw than at the front.
The pelvis was shaped like that of a modern human and was relatively narrow. This most likely allowed more efficient movement on two legs. Their spinal cord was also thinner than those of a modern human. This may have resulted in them having limited speech due to the lack of nerves needed for complex control of breathing whilst speaking.
The limbs were also very different. Unlike earlier species, the legs were now much longer than the arms and their tree climbing adaptations were gone.
The Homo ergaster species were the first to take advantage of the open environment. The development of a smaller gut and a bigger brain suggested that they relied on more nourishing food hence the reason it is believed that their diet included more meat then previous species.