There are four species of Mockingbird that inhabit the Galapagos Islands. Their beaks are different sizes and shapes but DNA evidence shows they likely all descended from a common ancestor species which reached the islands in a single colonization event. Why would scientists theorize that the mockingbirds had changed over time? A. The birds adapted to the availability of local food sources.
B. The birds adapted to the availability of local food sources.
C. The birds prefer a mate with an attractive beak.
D. The birds avoided humans as well as predators