Key ideas1 of 3
Number the feeding positions
A trophic level is a position in a feeding sequence. Start numbering at one for the producer, such as a plant or alga. A herbivore feeding on that producer occupies level two; its predator occupies level three. A predator eating that secondary consumer occupies level four. Follow the particular chain given: an organism eating several different foods can occupy different trophic positions in different feeding routes.
