Cycle chains and the LPA model

J. M. Cushing

Research output: Contribution to journalArticlepeer-review

21 Scopus citations


The LPA model is a three dimensional system of nonlinear difference equations that has found many applications in population dynamics and ecology. In this paper, we consider a special case of the model (a case that approximates that used in experimental bifurcation and chaos studies) and prove several theorems concerning the existence and stability of periodic cycles, invariant loops, and chaos. Key is the notion of synchronous orbits (i.e. orbits lying on the coordinate planes). The main result concerns the existence of an invariant loop of synchronous orbits that bifurcates, in a nongeneric way, from the trivial equilibrium. The geometry and dynamics of this invariant loop are characterized. Specifically, it is shown that the loop is a cycle chain consisting of synchronous heteroclinic orbits connecting the three temporal phases of a synchronous 3-cycle. We also show that a period doubling route to chaos occurs within the class of synchronous orbits.

Original languageEnglish (US)
Pages (from-to)655-670
Number of pages16
JournalJournal of Difference Equations and Applications
Issue number7
StatePublished - Jul 1 2003


  • Bifurcation
  • Difference equations
  • Equilibria
  • Invariant loop
  • Periodic cycles
  • Stability

ASJC Scopus subject areas

  • Analysis
  • Algebra and Number Theory
  • Applied Mathematics


Dive into the research topics of 'Cycle chains and the LPA model'. Together they form a unique fingerprint.

Cite this