Patterning in the cellular slime moulds.

The aim of the present article is to derive and illustrate in a simple form some of the important concepts in developmental biology. The development of the cellular slime mould Dictyostelium discoideum is an ideal model system for this purpose. I will outline the development of this organism at its multicellular stages and review some relevant studies focusing on the control of cell differentiation and pattern formation while deriving some key concepts in the current thinking about the control of development.