Final answer:
The names 'Australopithecus afarensis' and 'Australopithecus africanus' translate to 'southern ape from Afar' and 'southern ape from Africa,' respectively, referring to their origins. A. afarensis, known for the famous Lucy skeleton, was found in Ethiopia, while A. africanus was first identified in South Africa. Both species were bipedal and provide insight into early human evolution.
Step-by-step explanation:
The names Australopithecus afarensis and Australopithecus africanus refer to species of extinct hominins that are important for understanding early human evolution. 'Australopithecus' means 'southern ape' and highlights the genus's discovery in the southern hemisphere, specifically in Africa. 'Afarensis' derives from the Afar region of Ethiopia, where the famous skeleton named Lucy was found (KNM-AL-288). Conversely, 'africanus' points to the species being African. Both species were bipedal and had a mixture of ape-like and human-like features, with A. afarensis dating from 3.9 to 2.9 million years ago and A. africanus from about 2 to 3 million years ago.
While A. afarensis had a brain size roughly equivalent to a chimpanzee and demonstrated both arboreal and bipedal abilities, A. africanus had a slightly larger brain and showed more evidence of bipedality. The discovery of these species helped scientists understand that human evolution involved a combination of tree climbing and walking on two feet, with changes such as a wider pelvis in A. afarensis indicating a shift towards more efficient bipedal locomotion.