Which of the following anatomical features was NOT found on the skull of Homo erectus?
Postorbital constriction
A high forehead
An elongated skull
A protruding face
Brow ridges above the eyes
The correct answer and explanation is:
The correct answer is A high forehead.
Homo erectus is one of the earliest members of the genus Homo and had distinct features compared to modern humans. One of the notable differences is the absence of a high forehead, which is characteristic of later species like Homo sapiens. Instead, Homo erectus had a more sloping forehead, which was less pronounced than the vertical forehead seen in modern humans.
Here’s a breakdown of the features found on the skull of Homo erectus:
- Postorbital constriction: This feature refers to a narrowing of the skull just behind the eyes. Homo erectus exhibited a moderate degree of postorbital constriction, which is typical of earlier hominins and contrasts with the more rounded skulls of modern humans.
- A high forehead: As mentioned, Homo erectus lacked a high, rounded forehead. Instead, they had a more sloping forehead, which made their skulls appear lower and less vertical compared to modern humans.
- An elongated skull: Homo erectus had an elongated skull with a low, long shape. This feature is also considered an early adaptation, as their skull shape was designed to accommodate a larger brain compared to earlier species like Australopithecus.
- A protruding face: Homo erectus had a relatively protruding face, especially in comparison to modern humans. This trait is associated with a pronounced brow ridge and large jaw, which were adaptations that helped with the mechanical function of chewing and with withstanding environmental pressures.
- Brow ridges above the eyes: Brow ridges were prominent on Homo erectus skulls. These ridges are thought to serve several functions, including providing structural support for the skull and possibly offering protection to the eyes.
In summary, Homo erectus had a more primitive skull structure, lacking features like the high forehead, which developed in later human species.