Food chain – Sequence of feeding in an ecosystem.
The food is chained (food chain) in the sequence in which it’s eaten – linked together like a chain.
Like all food chains this one begins with a producer, which in this case is the oak tree. The next organism in the sequence is the caterpillar which eats the oak tree leaves. The caterpillar is the primary consumer which is then eaten by the next organism in the feeding sequence, the treecreeper (small bird), known as the secondary consumer. Finally, the treecreeper (small bird) is eaten by the tertiary consumer which in this food chain is the hawk.