LAUSR

Abstract During its 40 years of development, the assumptions of the Dynamic Energy Budget ( deb ) theory for metabolic organisation turned out hard to replace. To understand this, a reasoning is here presented for why its standard model has no alternatives with a comparable level of simplicity and will never have them. Energy and mass conservation rules are essential to quantify the eco-physiological development of an individual organism thermodynamically. These rules strongly constrain the mathematical modelling of this development. In combination with consistency with a small set of stylised empirical facts, the freedom of modelling the skeleton of the model is reduced to a single one: the standard deb model. This skeleton can, however, be extended in many different ways to capture particular ‘details’. The key-message of this paper is that the more simple metabolic models become, the more constraining are consistency conditions.