Answer:
Homologous features
If two or more species share a unique physical feature, such as a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor. Physical features shared due to evolutionary history (a common ancestor) are said to be homologous.
When two organisms share a common ancestor, their genetic code has to be similar. The extent of similarities determines how recently have the organisms evolved.
How do species evolve from a common ancestor?
Repeated branching events, in which new species split off from a common ancestor, produce a multi-level "tree" that links all living organisms. Darwin referred to this process, in which groups of organisms change in their heritable traits over generations, as “descent with modification." Today, we call it evolution.
