Figure 12.5 Predicting density-independent growth of the apple thrip. Scientists surveyed thrip populations on the flowers of rose bushes from 1932 to 1946. The dashed line represents the predicted number of thrips each year based on a model that included temperature and rainfall variables that cause density-independent effects on thrips. The bars represent the number of thrips actually observed each year.

Data from J. Davidson and H. G. Andrewartha, The influence of rainfall, evaporation and atmospheric temperature on fluctuations in the size of a natural population of Thrips imaginis (Thysanoptera), The Journal of Animal Ecology 17 (1948): 200–222.