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\iteman{ZMATH 2010b.00634}
\itemau{G\aa rding, L.}
\itemti{Food chains. (N\"aringskedjor.)}
\itemso{Normat. 57, No. 2, 74-77 (2009).}
\itemab
Summary: A food-chain is an ordered collection of populations feeding on each other. A simple linear model for the variations of the populations is introduced. A condition for stability, i.e., that the variations of the populations are bounded, is that all the eigenvalues of the corresponding matrices lie on the unit-circle. The populations will then vary cyclically. The condition gives some restrictions on the fertility and life-expectancies of the various populations. Special cases of simple chains are studied and compared with real-life data, with some remarkable good fits.
\itemrv{~}
\itemcc{M60 I70}
\itemut{mathematical modelling; linear model; stability condition}
\itemli{}
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