Hans Spemann was recognized for his research into the development of embryos, and in particular for his studies into the causes behind the specialization and differentiation of embryonic cells. In the mid-1930s, Spemann discovered "organizers"--regions within developing embryos that cause undifferentiated tissue to evolve in a specific way. For this finding he was awarded the 1935 Nobel Prize for physiology or medicine. In addition to these achievements, Spemann is credited with founding the early techniques of microsurgery, the minute manipulations of tissue or living structure.

The son of a well known book publisher, Spemann was born in Stuttgart, Germany. He was the eldest of four children of Johann Wilhelm Spemann and the former Lisinka Hoffman. The family, which was socially and culturally active, lived in a large home that was well stocked with books, which helped shape the young Spemann's intellect. Upon entering the Eberhard Ludwig Gymnasium...