Long food chains are in general chaotic
Thilo Gross, Wolfgang Ebenhöh and Ulrike Feudel
Oikos 109, 135-144, 2005

"Ingenious use of bifurcation theory"

Andre De Roos recommended this paper on FacultyOpinions (link)

"New Finding Interesting Hypothesis -- I found this paper very interesting as it shows that chaotic dynamics are likely to occur in any food chain model with more than three trophic levels. By means of an ingenious use of bifurcation theory, the authors show that chaos occurs independent of the form of the interaction functions between the trophic levels. In addition to these nice results, the paper contains one of the most lucid and illuminating summaries of the types of bifurcation that can occur in ordinary differential equation models."