Sahelanthropus tchadensis is one of the oldest known species in the human family tree.
The species lived between 7 and 6 million years in western Central Africa (Chad). Upright walking may have helped the species survive in diverse habitats – including forests and grasslands.
Despite having only Sahelanthropus skull material, studies so far indicates that primitive man was a combination of apelike traits and similarities to humans.
Its features include a small brain monkey (although a little smaller than a chimpanzee!) Head bowed, very prominent brow ridges and elongated skull.
Their human-like features include small canine teeth, a middle part of the face below, and an opening of the spinal cord below the skull rather than toward the rear, as well as in non-bipedal primates (or monkeys).
How do we know Sahelanthropus walked upright? Some of the earliest evidence of walking on two legs is Sahelanthropus.
The large opening (foramen magnum) into the base of the skull to the spinal cord connects the brain is placed below (the bottom of the skull) than in apes or any other primate except humans. This characteristic indicates that the head of Sahelanthropus was conducted in a body upright.