THE MAIA HYPOTHESIS

Initially the name Maia was given to a cybernetic approach to understanding the control of growth rate in cultured hydroids (Chapter 5). It was reasoned that this may indicate the underlying control of biosynthesis (Chapter 6). The aim was to find a technique to derive the output of the growth control mechanism from traditional cumulative data; and the idea was first applied to the growth of colonies (Laomedea) and, later, populations (Hydra). A feature of the approach, well known to cyberneticists, is to access the output of control mechanisms using perturbation experiments. The data are characteristically oscillatory, and exhibit cybernetic features such as ‘runaway’ and relaxation stimulation. The evidence was corroborated with data from a simulation model incorporating feedback, which reproduced the essential features of the hydroid output. This method was later applied to growth output in yeast cell suspensions with similar results (Chapter 12), which showed that the method was portable between taxa. There was reason to believe that the control requirements of other biological replicators might be similar, from the cell to more complex organisms. These experiments provided the inner loop of what proved to be a dual loop feedback mechanism.