* By weight: A blue whale, the largest animal on earth, eats the most *by weight* – up to 40 tons of krill per day!
* By percentage of body weight: The giant anteater, with its long snout and sticky tongue, consumes up to 30,000 insects per day, which is a massive amount compared to its own body weight.
* By frequency of eating: Some animals, like hummingbirds, need to eat almost constantly to maintain their energy levels.
So, the answer depends on how you define "biggest appetite." It's more accurate to say that different animals have evolved to have different appetites based on their needs and lifestyles.