Final answer:
Dr. Miller showed that the claim of irreducible complexity (IR) for the bacterial flagellum is incorrect by demonstrating that its parts can have other functions in different contexts.
Step-by-step explanation:
Dr. Miller's rebuttal of the irreducible complexity (IR) claim for the bacterial flagellum shows that IR is incorrect for this complex system. The bacterial flagellum is often cited as an example of irreducible complexity, meaning that it cannot function if any one of its many parts is missing or modified. However, Dr. Miller demonstrated that the parts of the flagellum can have other functions in different contexts, indicating that they could have evolved gradually through natural selection. For example, some of the flagellar proteins have been found to have similarities to proteins in the Type III secretion system, which is used by bacteria to inject toxins into host cells.