Explanation: An adaptation is adapted to suit the environment as every environment is different.
Different environment aids to different kind of adaptations that perfectly suits the animals living there.
The adaptation of an animal living in the desert region will have adaption to work in hot climate. The plant that grows in a desert area have no leaves and broad stem to store water.
The animals that live in the polar regions have thick fur to provide insulation and heat to live in polar region.
Charles Darwin had concluded that these birds had somehow evolved to adapt based on the island they were on. Each island had different food sources so if these finches wanted to survive they had to change. Each finch adapted to their environment due to forcefully evolving to survive.