Question

Species X is an extinct animal. A scientist has discovered fossils of species X and compared them to species Y, a living animal that inhabits the same area where the fossils were found. The scientist has noted that the two animals share several physical characteristics.

What can the scientist most likely conclude about the two types of animals?

Species X was better adapted to the environment.
Species X outcompeted species Y for food.
Species X is an early ancestor of species Y.
Species X mated with species Y and had unique offspring.

Answer 1

Species X is an early ancestor of species Y.

Reason: Shared physical characteristics in fossils and a living species from the same area most likely indicate a close evolutionary relationship (common ancestry). The other choices aren’t supported by that evidence (you can't infer competition, superior adaptation, or interbreeding from just morphological similarity in fossils).