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A Timeless 'Fish Tale' Laid to Rest: A Whale Shark Could Fit You in Its Mouth, But It Couldn't Eat You

The bubbles around me clear and as I regain my visibility my first

thought is how wide is the mouth coming for me. Five feet? Six Feet? 

Will my whole body fit in there?  As the whale shark closes the distance

between us mouth first, I'm focused entirely on the size of the beast... Just feet shy of its intercept course, it casually slips below me into

the ocean depths, emerging behind me unconcerned.  Thankfully, I'm no

Jonah and this is not my whale (or whale shark as the case may be).


A run-in with a whale shark like the one described above would probably scare the flippers off of most amateur fish fans, but to marine biologist Dr. Craig McClain, it's simply an occupational hazard, and one that he's not at all frightened of.

"I know that the esophagus of a whale shark measures only inches across," he writes.

"The massive beast could not choke me down even if it preferred man meat

to plankton."

shutterstock_88641523.jpgWhale sharks are the largest fish in the sea. Adults measure thirty-two feet from nose to tail fin and weigh about 20,000 pounds. Despite their behemoth size and prodigious maws, which tally in at 4.9 feet wide, these gentle giants don't concern themselves with larger prey. Instead, they primarily feed on millions and millions of tiny aquatic organisms -- plankton -- opening their mouths gaping wide to take in as many of the miniscule critters as possible, about nine pounds of them per hour during productive feeding sessions.

According to marine biologist Dr. Philip Motta of the University of South Florida, whale sharks aren't in the least bit interested in consuming humans.

"Having swam in front of many of them as they were filter feeding, I noticed that they closed their mouth as they approached me head on. One would have to actively try and get into their mouth while feeding, which I do not recommend," he told Real Clear Science.

But still, curiosity begs the question: what would happen should you -- against all odds  -- find yourself in mouth of a whale shark? 

First and foremost, you'd notice that it's a tight squeeze. The whale shark's pharynx isn't nearly as capacious as you might think. According to Motta, an average-sized man would barely fit.

If you can overcome any claustrophobia and the whole "being eaten" thing, you'd be afforded an inside look at some spectacular anatomy! Towards the mouth opening, you'd see about 3,000 teeth, each about three millimeters in length and curved slightly inward, arrayed in about 350 rows. The sheer number of teeth sounds daunting and dangerous, but unless you find yourself accidentally munched on the way in, you probably don't have to worry about them.

If oriented towards the front of the shark, look to your left and right; you'll notice ten black sieve-like filter pads; five on either side. These function to separate the food from all the water that's taken in.

If you have the courage and flexibility to look behind you, you'll see the esophageal opening, which leads to the stomach. Don't worry, as mentioned earlier, you won't be able to fit down the tube.

Chances are, however, that your sight-seeing session will be extremely brief.

"My educated estimate is that the shark would immediately spit out the person," Motta said.

In 2010, Motta led a study that focused on whale sharks' feeding anatomy and behavior. One thing he and his team found was that the animals really don't like eating anything that's foreign to their diet.

"We

actually threw seawater soaked rice in front of whale sharks to time

the flow of water into the mouth as they filter fed on the surface. They

would spit out the one handful of rice as soon as it entered the mouth. We also threw Sargasso seaweed in front of them and they spit that out also."

Whale sharks have a built-in "coughing" mechanism that's triggered when objects that clearly aren't food brush past their filter pads. This causes the whale shark to open its mouth and attempt to expel its contents.

So, to summarize, a whale shark almost certainly won't take you in its mouth, and it definitely couldn't eat you.

Sorry to spoil a timeless "fish tale."

(Image: Whale Shark via Shutterstock)