Debate continued, however, until 1915 when Thomas Hunt Morgan's work on inheritance and genetic linkage in the fruit fly Drosophila melanogaster provided incontrovertible evidence for the proposal.
Porén, o debate continuou ata que en 1915 Thomas Hunt Morgan, traballando sobre a herdanza e o ligamento xenético na mosca Drosophila melanogaster proporcionou probas incontrovertibles desta teoría.