Simplifying a physiologically structured population model to a stage-structured biomass model

André M. De Roos*, Tim Schellekens, Tobias Van Kooten, Karen Van De Wolfshaar, David Claessen, Lennart Persson

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

80 Citations (Scopus)


We formulate and analyze an archetypal consumer-resource model in terms of ordinary differential equations that consistently translates individual life history processes, in particular food-dependent growth in body size and stage-specific differences between juveniles and adults in resource use and mortality, to the population level. This stage-structured model is derived as an approximation to a physiologically structured population model, which accounts for a complete size-distribution of the consumer population and which is based on assumptions about the energy budget and size-dependent life history of individual consumers. The approximation ensures that under equilibrium conditions predictions of both models are completely identical. In addition we find that under non-equilibrium conditions the stage-structured model gives rise to dynamics that closely approximate the dynamics exhibited by the size-structured model, as long as adult consumers are superior foragers than juveniles with a higher mass-specific ingestion rate. When the mass-specific intake rate of juvenile consumers is higher, the size-structured model exhibits single-generation cycles, in which a single cohort of consumers dominates population dynamics throughout its life time and the population composition varies over time between a dominance by juveniles and adults, respectively. The stage-structured model does not capture these dynamics because it incorporates a distributed time delay between the birth and maturation of an individual organism in contrast to the size-structured model, in which maturation is a discrete event in individual life history. We investigate model dynamics with both semi-chemostat and logistic resource growth.

Original languageEnglish
Pages (from-to)47-62
Number of pages16
JournalTheoretical Population Biology
Issue number1
Publication statusPublished - Feb 2008
Externally publishedYes


  • Archetypal model
  • Consumer-resource
  • Food-dependent individual growth
  • Population dynamics
  • Population size-structure
  • Stage-structured model

Fingerprint Dive into the research topics of 'Simplifying a physiologically structured population model to a stage-structured biomass model'. Together they form a unique fingerprint.

  • Cite this