Ardipithecus Ramidus

Ardipithecus ramidus lived in the forests of Ethiopia about 4.4 million years ago ("Ardipithecus"). About fifteen years ago, a team of Ethiopian and American scientists, Tim White of Berkeley discovered fossil specimens of Ardipithecus ramidus. The age of Ardipithecus ramidus' fossils were found using paleomagnetic and radioisotopic dating methods. Paleomagnetic uses periodic reversals in the Earth's magnetic field while radioisotopic uses the rate of decay from one radioisotope into another. Ardipithecus ramidus is also known as "Ardi." Ardipithecus ramidus is a very early fossil hominid and was placed within the Australopithecus genus, which had found was different from australopithecines; Ardipithecus deserve a new genus of its own (Renne). Importantly, Ardipithecus ramidus linked to the hominin lineage. According to Paul Renne, these fossils were found from "a cluster of localties west of the Awash River, within the Afar Depression, Aramis, Ethiopia." It was reported in 1994 and 2009. White's team found over 100 fossils specimens of Ardipithecus ramidus. The first fossils that were recovered were pieces of her cranium, a mandible, teeth, and arm bones ("A hominid known"). Additional fossil specimens were found later in 1994. White and his colleagues came up with the name Ardipithecus ramidus ('ramid' means 'root' in the Afar language of Ethiopia and 'Ardi' means 'ground').

Ardipithecus ramidus was found surrounding by family. She was discovered about 46 miles away from where Lucy's species, Australopithecus afarensis was found in 1974 (Shreeve). Ardipithecus ramidus' specimens have some ape-like features; it also has human features like smaller canines ("Ardipithecus"). Ardipithecus ramidus' postcranial skeleton suggests that she had not evolved "obligate bipedality," which means it can walk upright for short distances or climb trees. She had a big toe that splays out from her foot like the apes to move between trees. Ardipithecus ramidus' foot contains a small bone inside the tendon that helps to keep the toe more rigid. She had a small brain and weighed about 110 pounds (Shreeve). Her cranial capacity is between 300 and 350 cc, which is smaller than a typical chimpanzee ("A hominid known"). Ardipithecus ramidus was about 3 ft and 11 inches tall. Some scientists suggested that it may be possible that Ardipithecus ramidus males did not compete against each other for dominance, therefore they did not need to be bigger in size. The skull of Ardipithecus ramidus is represented by the cranial vault, which is the part of skull that covers the brain, parts of the cranial base, and right half of its face (Renne). Her pelvis was shorter and broader than the apes. The large flaring bones of her upper pelvis were located so that Ardipithecus ramidus could walk on two legs without shifting side to side like a chimp (Shreeve). Her lower pelvis was built more like the apes. She also had a huge hind limb muscles from climbing trees. For modern chimps and gorillas, they vertically climb up the tree trunks and swing from branches, and knuckle-walk on the ground. According to Jamie Shreeve, researchers believed that Ardipithecus ramidus had a very flexible wrists and finger joints. She would have walked on her palms as she moved between trees. Ardipithecus ramidus definitely had some advanced characteristics and traits of much older hominin species and living apes.

Ardipithecus ramidus was an omnivore, which means she had a generalized diet consisting plants, meat, and fruits. She did not seem to eat any hard or abrasive foods, such as nuts and tubers ("Ardipithecus"). The dentition of Ardipithecus ramidus is well represented, including all types of teeth, such as canines, premolars and molars. She had strong crown asymmetries, "in particular enlarged