AP BIOLOGY

Detailed explanation-1: -The pelvic bones of whales are “one of the classic examples of a vestigial structure, ” said Otárola-Castillo. “But what we found was that the shapes of these bones are highly associated with the mating systems of these whales and dolphins-species that are more promiscuous have more-complex-shaped pelves.”

Detailed explanation-2: -1: Whale Skeleton: The pelvic bones in whales are also a good example of vestigial evolution (whales evolved from four-legged land mammals and secondarily lost their hind legs).

Detailed explanation-3: -A vestigial structure is a biological structure that has lost a major ancestral function and is usually drastically reduced in size. Well-known examples include the eyes of blind cave fishes and blind cave salamanders, and the diminutive wings of kiwis and emus.

Detailed explanation-4: -The pelvis and femur in whales are considered vestigial structures. These structures were inherited from ancestors that had a use for them, but are no longer used today. Whales evolved from animals that used to walk on land. Thus, these ancestors needed a pelvis and femur bones to do so.