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Abstract

The problem of complexity formation in the development of organisms has fascinated biologists for centuries. The contribution provides a historical perspective on research work in this field of developmental biology, starting at the beginning of the 20th century, when Theodor Boveri suggested that cell fates may depend on a graded distribution of some substance in the egg. In the 1920s, Hans Spemann discovered an organiser region in the newt embryo. In 1952, Alan Turing proposed a mathematical model to explain self-organisation from initially homogeneous states based on chemical interactions. In 1969, Lewis Wolpert coined the term ‘positional information’ and proposed a model of a gradient of a morphogen that elicits different responses depending on its concentration. In 1972, Gierer and Meinhardt formulated their gradient theory of local activation and lateral inhibition based on non-linear kinetics. This view was supported by mutant phenotypes in Drosophila. Systematic mutant screens in Drosophila and subsequent cloning of the genes have led to the identification of a large number of morphogenetic proteins.