Information processing in computational tissues

Biocomputation involves studying organisms using the metaphor of computers so we can discover both new ways of performing computation and defining living systems. An appropriate point to start any discussion of biocomputation is by contrasting the distinct properties of computers and biological systems. Only then is it possible to consider the concept of computation and whether some of the activities of both systems lie within our definition. As computers are man-made their properties are easily described: computers process symbolic information; they solve mathematical problems by algorithms. Physically they are composed of large, regular arrays of interconnected switches so that their component parts can interact in strictly controlled ways. This arrangement, called structural programmability, [Con85], gives computers the capability of simulating one symbol processing machine on another. The primary way of performing this simulation is recursion and sequence.