Question

A student argues that two species of birds are the same species because they have similar body structures, similar DNA, and similar beaks. Another student argues that the birds are different species because they have different color patterns and have a different mating season. Which piece of evidence supports the second student's argument?
The birds have similar body structure.
The birds have similar beaks.
The birds have different color variations.
The birds have different mating seasons.

Answer 1

The birds have different mating seasons.

Different mating seasons create reproductive isolation, which prevents interbreeding and is strong evidence they are separate species.