Snails faced a similar evolutionary trend to the peppered moths. The phenotypes of snail shell colors are affected by the intensity of the light, which increases within city limits. A phenotype is the observable characteristics of an organism that result from the interaction of its genes. While snail shells have always been a variety of colors, it was obvious to scientists that there was a sort of pattern. Within the confines of our urban cities, we generate a large amount of heat. This heat is reflected off of pavement and buildings and the lack of shade provides a very warm environment. Within city limits, snails are displaying the light-colored phenotype. Lighter colored snails have the ability to reflect sunlight off of their shell and keep the snail cooler. The dark colored snails cannot reflect as much heat or sunlight and have a tendency to overheat. Farther away from the city where the heat and sunlight are not as intense, the snails have darker colored shells as they are less likely to overheat and have the ability to find shaded areas (Lewis, 2019).