Anatomical evidences explain this evidence.

The study of comparative anatomy predates the modern study of evolution. Organisms with similar structures must have acquired these traits from a common ancestor. It can serve as the first line of reasoning in determining the relatedness of species. It's important examples are : Homologous organs - All mammals share the same pattern of forelimbs. Though they perform different functions, they are anatomically similar. This is called divergent evolution and the structures are called homologous structures (common ancestors). Analogous organs - The pair of organs is not anatomically similar, but performs the same function (e.g., the wings of butterflies and birds). This is called convergent evolution. hope it would be helpful✌

Anatomical evidences help us to study how species have evolved over a period of time. Analogous structures support the theory of evolution and explain the fact that how species build up adaptations in order to fit in an environment whereas homologous structures help us to understand common ancestry. A common example of comparative anatomy is the similar bone structures in forelimbs of cats, whales, bats, and humans.