On the regulatory nature of individual growth: some observations from freshwater snails

Various types of growth models are assessed. Results derived from observations made on growth in the freshwater snail, Planorbis contortus, suggest that in certain instances models based on a mechano‐reductionist philosophy are acceptable whereas in others they are untenable. In the latter case a holistic representation is more biologically satisfying. Q10 values provide a useful assessment and summary of an individuals regulatory capacity with respect to growth when temperature disturbances are experienced. Another parameter, kcorr is developed to carry out this function when other, particularly food supply, disturbances are involved.