One example of a vestigial organ that could be found in a transitional fossil is the pelvic bones in a whale. Whales are descended from land-dwelling mammals, and over time, as they adapted to aquatic life, their pelvic bones became vestigial and no longer serve a significant function. Transitional fossils of whales may show evidence of pelvic bones that are reduced in size and no longer connected to the rest of the skeleton, providing insight into the evolutionary history of these animals.
