Darwin’s observations of finches indicated descent with Modification in bills.<span> They had become adapted to eating different diets, </span>Beak shape of finches is affected by the type of food available to eat. Finches<span> are generally seedeaters and eat a variety of plant seeds. There are times though that their diet will be composed of insects and certain fruits, berries and vegetation.</span>
The air in the lungs has a higher concentration of oxygen than that of oxygen-depleted blood and a lower concentration of carbon dioxide. This concentration gradient allows for gas exchange during respiration.
