NEET BIOLOGY

Detailed explanation-1: -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.

Detailed explanation-2: -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-3: -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-4: -Both whales and dolphins have pelvic (hip) bones, evolutionary remnants from when their ancestors walked on land more than 40 million years ago. Common wisdom has long held that those bones are simply vestigial, slowly withering away like tailbones on humans.

Detailed explanation-5: -Researchers studying the pelvic bones of dolphins and whales reveal that these seemingly useless remnants of an ancient landlubber lifestyle actually have a purpose. Turns out, cetacean pelvic bones help control the motion of the ocean, and their size and shape are likely influenced by the forces of sexual selection.