can a food chain have a quaternary consumer without having secondary or tertiary consumer

Answer 1

Yes, but almost never. Typically predators so far up the food chain have specialized diets that aren't really open to changing. Consider a lion going after field mice when all the antelope die out. This isn't a 1:1, but the principle is the same. As for the animals that eat both primary and tertiary consumers, wouldn't they simply become the secondary consumer if all of their tertiary consumer prey dies out? The nature of the hierarchy necessitates that all the spots going up the chain are occupied. If they aren't, everyone just moves down a step.

Answer 2

thank you