Final answer:
Australopithecus afarensis lived between 3.9 and 2.9 million years ago in East Africa. The species is known for its bipedalism and arboreal features, with a brain size comparable to that of modern chimpanzees. Lucy, a notable fossil of this species, was discovered in Ethiopia.
Step-by-step explanation:
Australopithecus afarensis: An Overview
Australopithecus afarensis is a well-known early hominin species that lived in the regions that are now part of East Africa. The species thrived between 3.9 and 2.9 million years ago during the Pliocene epoch. One of the most iconic fossils representing this species is Lucy, an adult female A. afarensis discovered in the Afar region of Ethiopia and dated to around 3.24 million years ago. Morphological evidence such as long and curved finger and toe bones suggests they may have spent time both in trees and on the ground bipedally. Their endocranial capacity was approximately 400 cubic centimeters, akin to that of a modern chimpanzee, and their anatomy exhibited significant differences from modern humans, notably in jaw shape and brain size.
Further fossil discoveries of Australopithecus afarensis have been made in Kenya and Tanzania, adding to our knowledge of their physiology and behavior. The study of species such as A. afarensis and others like Australopithecus africanus, Australopithecus bahrelghazali, and Australopithecus garhi continues to provide valuable insights into human evolution and the changes that occurred over millions of years in the genus Australopithecus.