The papers presented by the American Association of Advancement of Science (AAAS) provide an in depth analysis of the features of Ardipithecus ramidus as the missing link. The hominid fossils are approximately 4.4 million years old, and present close to 36 fragments, including parts of the skull and the pelvic girdle. The publications cover a number of themes, which include anatomical parts of the human evolution that show that Ardipithecus ramidus dwelt on land could climb trees as well, the habitat occupied by Ardipithecus ramidus based on thousands of fossils excavated at Arima as well as rock components, among others.
The skull of Ardipithecus ramidus is of great importance as it enables the establishment of the link between ancient man and the present day man, in terms of brain size and shape of the skull and the face. Suwa et al. (2009) notes that Ardipithecus ramidus had a relatively smaller brain, of between 300 to 350 cubic centimeters, compared to its successor, Australopithecus which had a brain size of about 400cc. This brain size is just about that of female chimpanzees. Suwa et al. further observes that Ardipithecus ramidus had a smaller skull, an indication that it was not adapted to heavy chewing. However, it had a projecting muzzle typical of Sahelonthropus, a fete that gave it an ape-like appearance. Suwa et al further notes that the ridge above its eye socket is slightly different from that observed in chimpanzees, and that the lower part of its face does not project forward as is the case with chimpanzees. In addition, the bottom of the skull of Ar ramidus show that it had a short cranial base, as was the case with Australopithecus. These features point to the fact that despite the small brain Ardipithecus ramidus had, it was already developing hominid-like aspects. Furthermore, Andrea () confirms that even though Ardipithecus ramidus has many apelike features, it has a number of borrowed