Final answer:
The two variations of the gracile Australopithecus are Australopithecus afarensis and Australopithecus africanus. A. afarensis had a mix of ape-like and human-like traits, while A. africanus had a slender build and bipedal locomotion.
Step-by-step explanation:
The two variations of the gracile Australopithecus are Australopithecus afarensis and Australopithecus africanus.
Australopithecus afarensis lived between 3.9 to 2.9 million years ago and had a morphology similar to a great ape, with long arms and curved finger and toe bones. However, its pelvis suggests it also moved bipedally, like modern humans.
Australopithecus africanus lived between two and three million years ago and had a slender build and bipedal locomotion. Its brain was larger than A. afarensis but smaller than modern humans.