Australopithecus Afarensis :: essays papers

Australopithecus Afarensis The species A. afarensis is one of the better known australopithecines, with regards to the number of samples attributed to the species. From speculations about their close relatives, the gorilla and chimpanzee, A. afarensis’ probable social structure can be presumed. The species was named by Johanson and Taieb in 1973. This discovery of a skeleton lead to a heated debate over the validity of the species. The species eventually was accepted by most researchers as a new species of australopithecine and a likely candidate for a human ancestor. Australopithecus afarensis existed between 3.9 and 3.0 million years ago. The distinctive characteristics of A. afarensis were: a low forehead, a bony ridge over the eyes, a flat nose, no chin, more humanlike teeth, pelvis and leg bones resembled those of modern man. Females were smaller than males. Their sexual dimorphism was males:females; 1.5. A. afarensis was not as sexually dimorphic as gorillas, but more sexually dimorphic than humans or chimpanzees. A lot of scientists think that Australopithecus afarensis was partially adapted to climbing the trees, because the fingers and toe bones of the species were curved and longer than the ones of the modern human. A. afarensis is classified as an ape, not a human. It is a Hominid, which is an ape closely related to human beings. The first fossils of a skeleton were found at Hadar; a site in northeastern Ethiopia. The team named the skeleton â€Å"Lucy† after the Beatles song, â€Å"Lucy in the Sky With Diamonds.† In terms of overall body size, brain size and skull shape, "Lucy" resembles a chimpanzee. However, A. afarensis has some surprisingly human characteristics. For example, the way the hip joint and pelvis articulate indicates that "Lucy" walked upright like a human, not like a chimp. This means that upright posture and bi-pedalism preceded the development of what we would recognize as human beings and human intelligence. All non-human primates sleep in the trees at night. So, it would seem to be that A. afarensis slept in trees also. Their skeletal structure agrees with their arboreal lifestyle. â€Å"The large premolars of A. afarensis suggests they were frugivores, and the thick enamel on the teeth suggests they may have eaten nuts, grains, or hard fruit pies† (Boyd and Silk, p.