Answer:
Biogeography: Animals can come from certain areas and move to other areas causing their adaptations and therefore traits to change.
Radioactive Dating: The time zone fossils come from can be dating to certain times where there species may have changed. This can also be said for Fossils.
Comparing anatomy and development: There characteristics of certain biological features can differentiate species and their traits to determine which animal has came from another and other relative species.
Genetics and Molecular Biology: Genes can be passed onto on another and looking at genes passed down from one species to the next determines evolution of traits.