S. stercoraria's phenotype has been shown to vary seasonally, latitudinally, and altitudinally. Seasonal variation occurs in S. stercoraria as a result an adaptive response to time constraints on development due to temperature changes. In the fall, as the temperature becomes cooler, the flies are able to increase development rate, so they can achieve the necessary, albeit smaller than average, size. Furthermore, S. stercoraria development rate increases with increasing latitude. This is likely an adaptive response to shorter mating seasons. Body size, but not development rate, vary with altitude. Dung flies are larger at higher altitudes as a result of colder temperatures.