Question

a scientist is studying the embryos of different animals. she notices that whale embryos grow small hind limb buds, but these disappear before birth. she compares this to land mammals, which also have limb buds. however, in land mammals, the limb buds remain and continue to develop until the adult stage. how does this support the theory of evolution? whale embryos grow hind limbs, but these disappear before birth. they do not serve any evolutionary purpose. whales developed hind limb buds from a genetic mutation. their ancestors never walked, and it happened by chance. whales had ancestors that lived on land and had legs. over time, they adapted to life in water and lost their hind limbs. whales and other sea animals have always been different from land mammals. they are not related through evolution.

Explanation:

The presence of hind - limb buds in whale embryos that disappear before birth suggests a vestigial structure. Vestigial structures are remnants of organs or structures that were functional in ancestors but have become non - functional or reduced in size over time due to evolutionary changes. This indicates that whales had ancestors that lived on land and had legs, and over time, as they adapted to life in water, they lost their hind limbs.

Answer:

Whales had ancestors that lived on land and had legs. Over time, they adapted to life in water and lost their hind limbs.