The beak sizes and shapes of Darwin's fiches are different because of survival of the fittest. The finches that had beaks that could get the food survived while the other died off. Thus, the number of those survived finches increased while the others decreased. The type of food available in each environment is different from the other, which is why they have different sizes and shapes.
Hey there! Darwin's finches had different beak sizes and shapes because of natural selection. Over time, the more desirable traits become more dominant and distinct. These beaks were best fit for the type of food the bird ate. Smaller-beaked birds usually have a seed diet, and larger-beaked birds usually eat large nuts or small creatures like worms and bugs. Hope this helps!
