Sahelanthropus Research Paper

Sahelanthropus tchadensis has a skull with an elongated shape with a relatively short, vertical face, which is set high relative to the skull vault. The eyes are set far apart from each other and have a very large continuous bony brow ridge above them. Examination of the lower jaw reveals that Sahelanthropus had a total of thirty two teeth, which is common in all Old World monkeys, apes, and humans. The foramen magnum (where the skull opens for spinal cord passage) is positioned forward and oriented downward. Sahelanthropus has a nose opening that a midline reaches down to the bony palate, as seen in gibbons and monkeys. By contrast, humans and African apes have a nose opening that is set well above the mouth even at its midline.
Sahelanthropus had a very primitive-looking braincase, especially in the back, combined with fairly advanced hominid-looking face and canine teeth. (source: Intro to Physical Anthropology, pg 292). Sahelanthropus' diet is not confirmed, but its flooded grassland/woodland habitat suggests that it probably ate leaves, succulents, and the roots and bulbs of submerged grasses and herbs.
Most of the species identified near the Sahelanthropus either have yet to be identified or are long since extinct.
These include giant saber-tooth cats, an unidentified leaf-eating monkey, elephants with four tusks, a large water-loving relative of pigs, prehistoric giraffes, three-toed horses, pigs, and an unidentified relative of musk ox. There are also three different hyena species, all abundant and representing genera that are now extinct. The abundance of kob, roan, hippopotami, and the presence of crocodiles and pythons suggest large tracts of flooded grasslands and thin woodlands as occur along the Lake Chad shore today. Discovery of Sahelanthropus' fossils were found in the Djurab Desert of northern Chad, at a site known as Toros-Menalla (source: Intro to Physical Anthro, pg
270). It is estimated that Sahelanthropus is about seven million years old. What evidence there is has not been reliable enough to definitively classify Sahelanthropus into the human-great ape group. Because of this, as well as its geological age difference and geographical distance from the less complete Orrorin and Ardipithecus, a separate species and generic designation for Sahelanthropus tchadensis is appropriate. Djimdoumalbaye Ahounta is created with finding the Sahelanthropus skull in July of 2001. The name Sahelanthropus tchadensis has a dual meaning. Sahelanthropus literally translated means "man from the Sahel." The species name "tchadensis" was assigned in recognition of all the fossil specimens recovered in Chad.
Australopithecus anamensis has an orangutan-like snout, distinguished by the front teeth and canines, which are set well forward of the cheek bones and protrude from the face The cheek bones attach at the level of the first molar. The jaws are narrow from side to side with long parallel tooth rows, resembling those of great apes. Enhancing this view, the lower jaw has a strongly receding chin. The ear, on the other hand, has a relatively narrow diameter, which is chimpanzee-like and differs from the wider ear canal of later Australopithecus and Homo. Also distinguishing A. anamesis from humans and later Australopithecus, it has a large variation tooth size, varying from the premolar, which only has a single large cusp, to the first milk molar, which is narrow with a large dominant cusp and minimum surface area for crushing, and overall small molars with thick enamel. This suggests that Australopithecus anamesis probably ate fruits but may have included more abrasive items, such as seeds, leaves, and bark.
Australopithecus afarensis (Lucy) has a very large skull, with an equally large face. The cheek bones are very wide from top to bottom and side to side, projecting out to the sides considerably past the eye sockets. Despite the width of the face, the eye sockets are relatively close to each other and the upper nose is narrow. The nose opening is elongated and tear-drop shaped. The nose opening is narrowly separated from the mouth. The upper jaw juts to past the face, creating a noticeable orangutan-like snout. The skull lacks a forehead, and the braincase behind the eye sockets is narrow from side to side.
Australopithecus africanus exhibits many human-like skull features. As in humans, the face is relatively flat and vertically disposed, and the jaw is relatively short. The neck muscles attached low on the skull, and the foramen magnum is positioned forward and oriented more downwards than in African apes.