Wieschaus was born in South Bend, Indiana, in 1947 but grew up in Alabama. He received his bachelor's degree in biology from the University of Notre Dame in 1969 and his doctorate from Yale in 1974. His doctoral dissertation involved using genetic methods to label the progeny (offspring) of single cells in fly embryos. He showed that even at the earliest cellular stages, cells were already determined to form specific regions of the body called segments.

Wieschaus began his Nobel-winning work in the latter part of the 1970s. The Alabama native spent three years with Christiane Nüsslein-Volhard in the European Molecular Biology Lab at the University of Heidelberg, Germany, tackling the question of why individual cells in a fertilized egg develop into various specific tissues. They elected to study Drosophila, or fruit flies, because of their extremely fast embryonic development. New generations of fruit flies can be bred in...