Final answer:
Lucy is an example of Australopithecus afarensis, and the Taung child is an example of Australopithecus africanus. Both are species within the subfamily of Australopithecus, which are significant in understanding human evolution.
Step-by-step explanation:
The subfamily of Australopithecus includes several species, but Lucy is best known as a member of Australopithecus afarensis. Australopithecus afarensis is an early hominin species that lived approximately between 3.9 and 2.9 million years ago. Lucy, found in Ethiopia and dating back to about 3 million years ago, represents this species and is significant due to her well-preserved fossilized remains, which provided substantial insights into early human evolution.
On the other hand, the Taung Child is an example of Australopithecus africanus, another species within the subfamily. This specimen was discovered in Taung, South Africa, and shares some traits with modern humans while retaining others that are more primitive. Analysis of the Taung Child's skull shows a mix of human-like features and others that are more typically associated with apes.