Just like in humans animals like monkeys for example share DNA. They evolve over time for whatever reason to survive. Think about bears and the similarities and differences based on where they live or animals being able to eat certain things they wouldn't have been able to before, because that plant life is now extinct.
Answer: First, we'll look at several types of evidence (including physical and molecular features, geographical ... It's unlikely that such similar structures would have evolved independently in each species
