Human Evolution

Human Evolution

Ardipithecus ramidus

This species was announced in September 1994. It is thought to be the oldest known hominid species. It was dated at 4.4 million years old. The majority of the fossils found were skull fragments. Other evidence suggests that this species was bipedal. The

individuals were about four feet tall. Some fossils found indicate that ramidus may have been a forest dweller. The teeth resemble something between earlier apes and A. afarensis. The fossils were discovered by a team led by Tim White in Aramis Ethiopia. The

find consists of 17 individuals.

Australopithecus anamensis

This species was named in August 1995. The fossils were mostly found in Kanapoi Kenya in 1988. Anamensis is thought to have existed between 4.2 and 3.9 million years ago. The teeth and jaws are very similar to those of older fossil apes. A partial tibia supports bipedality. The first fossil of this species was found in Kanapoi Kenya by Bryan Patterson. The fossil was a lower left humorous

dated to be about 4.0 million years old.

Australopithecus afarensis

This species existed between 3.9 and 3.0 million years ago. It had an apelike face with a low forehead, a bony ridge over the eyes, a flat nose, and no chin. They had protruding jaws with large teeth. The skull is similar to that of a chimpanzee except for more human like teeth. The canines of this species were smaller than those of earlier apes but larger than humans. Their pelvis and leg bones left no doubt that they were bipedal. They had similar hands to humans and were about 3.5 to 5.0 feet tall. Footprints of this species were discovered in 1978 by Paul Abel at Laetoli in Tanzania. The estimated age is 3.7 million years old.

Australopithecus africanus

A. africanus lived between 3 and 2 million years ago. Their body sizes and brain sizes were slightly larger than afarensis. The shape of their jaw was fully parabolic, like that of humans, and the canine teeth have reduced in size. This species fossils were discovered by Raymond Dart in 1924 at Taung in south Africa. The find consisted of a full face, teeth and jaws, and an endocranial cast of the brain. It is between 2 and 3 million years old.

Australopithicus garhi

It is known from a partial skull that differs from previous australopithecus species in the combination of its features. They had extremely large teeth especially the rear ones. The skull was discovered by Y. Haile-Selassie in 1997 at Bouri in Ethiopia. It is about 2.5 million years old.

Australopithecus aethiopicus

A. aethiopicus existed between 2.6 and 2.3 million years ago. This species is known from the Black Skull specimen discovered by Alan Walker in 1985 near West Turkana in Kenya. The specimen is almost completely intact. It has a small cranium capacity for a

hominid and has a strange combination of primitive and advanced features. This species possessed the largest sagittal crest in any known hominid.

Australopithecus robustus

A. robustus had a body similar to africanus but a larger and more robust skull and teeth. It existed between 2 and 1.5 million years ago. The massive grinding teeth indicate that this species had to chew tough food. The first robustus fossils were discovered by a

schoolboy in 1938 at Kromdraai in South Africa.

Australopithecus boisei

This hominid existed between 2.1 and 1.1 million years ago and was very similar to robustus, however the face and cheek teeth were larger. Its brain size was also very similar to robustus. The first boisei fossils were discovered by Mary Leaky in 1959 at Olduvia Gorge in Tanzania.

Homo habilis

H. habilis existed between 2.4 and