What can be more amazing than an embryo’s development? How do the cells “know” that the eyes go on the face and not on a leg or some other part of the body? And why does this information sometimes go awry — giving rise to a deformed creature? Walter J. Gehring, a renowned specialist in the genetics of embryonic development, traces recent developments in the field. He describes the fierce competition within the scientific community to discover the genes that control the universal blueprint of development, which is followed by all complex living organisms, from the common fly to human beings. He views the main asset of this cut-throat competition as “clairvoyant opportunism”. Nonetheless, human beings are finally beginning to understand how they are made.

Walter J. Gehring teaches cellular biology at the University of Basle, Switzerland. He has received numerous scientific prizes for his research in the biology of development.