NTRODUCTION The size of a plant's leaves is a balance between the need for light for bigger leaves and the need to conserve water for smaller leaves. The purpose of this lab was to compare two populations of California Buckwheat plants to see if different conditions of light have influence on their leaf size and structure. It is predicted that shady conditions, the plant may have larger leaves as a result of natural selection. A plant with larger leaves would be able to gather more sunlight, therefore making more carbohydrates, and thus produce more flowers and seeds than a plant with smaller leaves. This process then increased the plants reproductive success and as a result more larger leaved plants in shady habitats. Natural selection would