Here's why:

* Food chains are simple, linear models that show the transfer of energy from one organism to another.

* The series of events starts with a producer (like a plant) that makes its own food through photosynthesis.

* The producer is then eaten by a consumer (like a herbivore), which then gets eaten by another consumer (like a carnivore), and so on.

* Each step in the food chain is called a trophic level.

Let me know if you'd like a more detailed explanation of food chains!