This article describes and evaluates Gilbert Gottlieb's role as an intermediator between psychology and evolutionary biology. He proposed that altered developmental conditions gave rise to new behavioral phenotypes (behavioral neophenotypes) that could provide the basis for initiating speciation. As an example, Gottlieb cited sympatric speciation of two species of fruit flies (Rhageletis pomella), which he believed was based on an ontogenetic shift in pupal feeding on apples or hawthorn fruit which determined their adult selection of apple or hawthorn trees for ovipositing. Recent evidence has provided additional links in the process of speciation of these fruit flies. Unlike other efforts to incorporate evolution in psychology, Gottlieb's theoretical contribution was based on actual evolutionary processes including recent developments in the field of evo-devo.