The exponential growth model was developed by Thomas Robert Malthus. Malthus developed this model as a result of his theory that any species can increase in number according to a geometric series. He believed that species with no overlapping populations or hindrances would increase in number if they reproduced.
The exponential growth model has three outcomes: the species population decreases; the species population increases; or the species population remains the same. The exponential growth model has three assumptions: species population has continuous reproduction not based on seasons; all species and organisms are identical with no age structure; and the environment is constant in space and time with unlimited resources.
It has been found that the exponential growth model exhibits accurate precision even if the assumptions are not met. However, the assumption that all species and organisms are identical with no age structure no longer holds true. Species and organisms differ in age, survival, and mortality rates. Species with a large number of organisms vary in their birth and mortality rates, so these numbers are averaged. The exponential growth model is most frequently used in microbiology, conservation biology, insect reproduction, plant/insect quarantine, and the dynamics of fish populations.