ABSTRACT
A second application is presented in this chapter: to the problem of energy and nutrient budgets in mammals. The differential inclusion formalism is used, not only to (largely) justify the classic models due to Pütter, Bertalanffy, and Kooijman, but also to explain how and why these models break down under extreme conditions. In essence, a biological system under ‘stress’ is liable to leave a given lower-dimensional `homeostatic’ manifold contained within X https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429026508/4614e5f6-5f02-45e5-afec-5950c67b94fb/content/inline-math6_111.jpg"/> . This explains why models without an intensive state variable or with just a single one (e.g. generalised ‘energy density’), which perform very well under a wide range of circumstances, are yet found to be generally inconsistent.
