Sahelanthropus tchadensis is considered to be one of the oldest ancestors in the human family tree. The time of existence is dated back to 7 or 6 million years ago. The territory of living, as supposed, was West-Central Africa. Even though this species could already walk upright, they are still considered to be human-like, but not actually human. There is a number of reasons behind this.
First of all, Sahelanthropus tchadensis still had a lot of ape-like features. Primary among them was a possession of a small brain. Most scientists say the size of it was even slightly smaller than the one of chimpanzee’s. Other features, considered as ape-like were, for example, sloping face, prominent brow ridges and elongated skull. All those features made Sahelanthropus tchadensis more of an ape than human. Despite all the human-like features these species had, like walking upright, small canine teeth, short middle part of the face and specific structure of spinal cord, they are still not considered to be human.
It is more likely to say that this creature is an ancestor of human and chimpanzees than to human solely.