A scientist argues that two species of birds are the same species because they have similar body structure, similar DNA, and similar beaks because they eat the same food. The birds do have some variations in color patterns and have a different mating season. Which piece of evidence would go against this argument and suggest that the birds are actually different species?
The birds have similar body structure.
The birds have similar beaks.
The birds have different color variations.
The birds have different mating seasons.