Taylor's power law: before and after 50 years of scientific scrutiny

Taylor's power law is one of the mostly widely known empirical patterns in ecology discovered in the 20th century. It states that the variance of species population density scales as a power-law function of the mean population density. Taylor's power law was named after the British ecologist Lionel Roy Taylor. During the past half-century, Taylor's power law was confirmed for thousands of biological species and even for non-biological quantities. Numerous theories and models have been proposed to explain the mechanisms of Taylor's power law. However an understanding of the historical origin of this ubiquitous scaling pattern is lacking. This work reviews two research aspects that are fundamental to the discovery of Taylor's power law and provides an outlook of its future studies.