In the 1980s, the use of polyacrylamide gel electrophoresis (PAGE) was popular. But more recent developments in other electrophoretic techniques have resulted in this method being less widely used. However, it is adequate for the needs of naturalists for issues which do not require high-performance methods, such as in systematics, phylogeny, studies of intraspecific ordinal variability, ecology and ecophysiology. We illustrate the application of PAGE by the results of a research program on marine and terrestrial invertebrates which was conducted from 1979 to 1992, but which is still used to initiate graduate students to the research. Thus, issues faced by the zoologist can be clarified by this method, not yet obsolete and still useful in natural history despite considerable advances in other electrophoretic methods*.