Orrorin tugenensis
Guide to Sahelanthropus, Orrorin and Ardipithecus
These fossil species between 8 million and 4.4 million years old include some of the earliest members of the hominin lineage.
![Ardipithecus hand skeleton next to a human hand X-ray image](/content/images/size/w1460/2023/10/ardipithecus-hand-human-x-ray-hand-composite-1.jpg)
Have Sahelanthropus and Orrorin been written out of existence?
A big argument about the so-called savanna theory comes with a surprising claim about the earliest possible hominin fossils.
![Artistic image of a skull of Sahelanthropus enshrouded by fog and clouds](/content/images/size/w1460/2022/08/sahelanthropus-tchadensis-skull-blending-into-fog-ryan-somma-cc-base-image.jpg)