Studying the world's largest animal, the blue whale, has been challenging to say the least, but scientists now know more about how this huge species feeds.

A study published in the latest issue of Nature reveals that these whales and their other big relatives have a special sensory organ in their jaws that controls eating.

The discovery sheds some light on how blue whales can fuel their impressive girth. They grow up to 110 feet in length and weigh about 300,000 pounds. The heart alone is the size of a small car.

NEWS: Blue Whales Keep Getting Bigger

Whales could eat a person, as the biblical story of Jonah and the Whale suggests. But thankfully whales, even killer whales, don't crave us and would prefer to consume other things. The primary chow of blue whales is actually minute krill and tiny crustaceans known as copepods. Lots of them.

To do this, blue and other rorqual whales feed by lunging and gulping substantial volumes of prey-laden water, a process that is unique among mammals. The whales have throat pleats that can expand to hold large volumes of water. According to the study's findings, the sensory organ is what prompts the whale to open its jaws and allows the throat to expand to full capacity.

VIDEO: Researchers stumble upon a pod of sperm whales getting some sleep in the open ocean.

NEWS: Do Dolphins Sleep Talk in Whale?

Nicholas Pyenson, a National Museum of Natural History paleobiologist, and his team write in the Nature article that "this organ provides the necessary input to the brain for coordinating the initiation, modulation and end stages of engulfment."

Isn't "engulfment" a good word? It reminds me of competitive eaters like Joey Chestnut wolfing down dozens of hot dogs.

Maybe someday scientists will determine what about Chestnut and other such eaters allows them to do what the rest of us can't. For now, at least we have a better idea on how the world's biggest aquatic and marine animals have evolved solutions to the challenges of feeding in the water while maintaining large body sizes.