Final answer:
The muscle group that does not have an origin on the pelvic girdle is the hamstrings.
Step-by-step explanation:
The muscle group that does not have an origin on the pelvic girdle is the hamstrings. The hamstrings include three muscles: the biceps femoris, semitendinosus, and semimembranosus. These muscles originate from the ischial tuberosity, which is part of the pelvis, but not specifically the pelvic girdle.