What are food chains and food webs?

A food chain shows energy transfer through feeding in a simple sequence; a food web connects many such chains in one environment.

Energy flow

Plants or algae can produce organic matter using light; herbivores eat them, and predators may hunt other animals. Decomposers use dead material in nutrient cycling. Arrows usually point from the organism eaten to the consumer to show energy transfer. Being a top predator does not mean eating just one thing everywhere. Many animals use different foods across seasons.

Why networks matter

Decline of one prey species may affect several predators, though alternative foods can change the response. Habitat change and pollution also alter connections. A simple chain is useful for teaching, while real ecosystems are complex webs. NOAA illustrates marine relationships from tiny producers through fish and birds. Understanding a connection requires place and time as well as species names.