Step 1: Australopithecines are an extinct genus of hominins that lived in Africa approximately 4 to 2 million years ago. They are considered one of the earliest ancestors of modern humans.
Step 2: They are characterized by both ape-like and human-like features. Australopithecines had a smaller brain compared to modern humans, but they walked upright, which is one of the key traits distinguishing them from other primates.
Step 3: Some well-known species of Australopithecines include *Australopithecus afarensis* (e.g., "Lucy") and *Australopithecus africanus*.