Food chain

A food chain is a linear sequence of organisms through which energy and nutrients flow, from primary producers to apex predators. Each organism occupies a single trophic level and feeds on the organism below it. The food chain is a pedagogical simplification: no real ecosystem operates through single linear pathways. Every species in a functioning ecosystem participates in a food web — a network of multiple interacting chains. The food chain persists as a concept not because it describes nature accurately, but because it provides an accessible entry point to the more complex reality of trophic dynamics. The linear model was useful in the early history of ecology, but its continued dominance in textbooks is a case of didactic inertia overwhelming empirical accuracy.