This activity engages students in learning about the mechanism of natural selection using candies to represent individuals of a species of clam.

Students begin by making observations about two containers of candies that they are told represent individuals from two strains of a species of clam. They then perform an experiment to determine which “strain” has a harder shell and graph the data. They then use these data to make a claim about which “strain” is more likely to survive in the presence of an arthropod that can eat a clam by crushing its shell. At the end of the activity, they examine several statements about natural selection and identify the one most likely to be accurate.