Food Web Diagram

sun <-- lettuce <-- meerkat <-- lion <-- mushroom
sun <-- peanut plant <-- bunny <-- fox <-- fungus
sun <-- potato <-- mouse <-- owl <-- slug

If the primary consumers became extinct, then the secondary consumers would have to become vegetarians. But for the secondary consumers, this is not their proper diet, and therefore, they would starve to death. Sooner or later, they would all die and become extinct as well. The primary consumers and secondary consumers would both be removed from the food chain. There would not be any more animals in the world, and the producers and decomposers would no longer be in use anymore. (This removes the primary consumer, secondary consumer, producer, and decomposer.)