Answer:
The finches on Galapagos Islands had different beak
The beaks of the finches changed over time
The Galapagos finches had a common ancestor
Explanation: Darwin's Finches are a good example of natural selection and adaptive radiation of evolution. The different finches in Galapagos Island have emerged from a common black, seed eating, short beak finches. This is called adaptive radiation, where different species arose from a single ancestor.
Due to changes in the natural environment, food resources, some finches have a long beak. This long beaks help them to eat insects. As a result, the competition will be less and nature selects them to survive in the new environment. This is a natural selection of evolution.
The answer is long
The bone indicated by the arrow is femur bone. It should be classified as the long bone. Other example for long bones would be tibia and fibula. Short bone would be carpal or tarsal bones. Flat bone could be found in skull. Irregular bone would be the vertebrae or pelvic.