the sheets were designed by ethel kessler and illustrated by artist john d. dawson for the usps. the original idea for the series, conceived 1996, was for a set of four american desert stamps. this was inspired by the success of "desert plants" commemorative stamps released in 1981. artist john d. dawson was recommended by art director howard paine and selected for the illustration of these four stamps. paine had worked with dawson on three previous usps issues: "american cats" (1988), "idaho statehood" (1990), and "flowering trees" (1998). from four stamps the idea expanded into a proposed set of six stamp sheets covering six ecosystems. after the commercial success of the first sheets the usps decided to extend the series by six more ecosystems from the sonoran desert to the hawaiian rain forest.