Aiden watched the Animation "Natural Selection" to learn about how giraffes got their long necks, and he used the PhET Interactive Simulation "Natural Selection" to manipulate rabbit fur color, tooth size, ear height and limiting environmental factors to see how variations within the rabbit population responded. He read the scientific text "Natural Selection" by Charles Darwin, and he read the text "Peter and Rosemary Grant" which discussed the naturalists' work with the finch populations on the Galapagos Islands.