'Aquaman': Director's Scientific Explanation for Water Vomiting Falls Flat

The big sell for December’s Aquaman is that this time around, Aquaman is going to be cool. The 60s-era orange spandex and coiffed Ken doll hair gets traded in for Jason Momoa’s rockstar swagger and some indication that director James Wan cares about the film’s scientific integrity. In a recent interview, he revealed a scientific reason why Aquaman and other Atlanteans can breathe on land and underwater. It’s only partially right.

In an interview with Screen Rant published Monday, Wan explained that when Atlanteans shift from breathing water to breathing air, they puke water:

“People would ask me, you know, ‘So when they talk, is it bubbles that come out of their mouth?’ And I’m like ‘No because there’s no air in your lungs, so there wouldn’t be any bubbles.’ . . . The first thing he does [Orm] is, he’s in an air pocket, so he’d puke out all the water that’s in his lungs. So that’s the first step. We think about all these little details and stuff like that. And then when he’s screaming [when the water returns], we want bubbles coming out of his mouth because now there’s actually air in his lungs.”

Wan’s effort to be scientifically accurate is nice, but it doesn’t quite check out. That’s fine! It’s a movie. But Michael Moore, Ph.D., a senior scientist at Woods Hole Oceanographic Institution, explains that casually puking up water doesn’t really have a place in respiratory marine science.

“To me, throwing up is a gastric rather than respiratory event,” Moore tells Inverse, “but fact can be stranger than fiction.”

*Aquaman* science: Puking is unnecessary. Giphy

The nearest analog he’s seen to Aquaman’s puking is what happens when large whales resurface. In his research, Moore follows whales with a high-resolution drone to see what happens when they come up for air. Most whales and dolphins come up for air about every 20 minutes, but sperm whales can stay submerged the longest — sometimes up to 90 minutes.

When whales resurface, says Moore, “they do have sea water sloshing in and out of their upper respiratory tract when they breathe.” But it’s not the same as the water puking process Wan hints at. “They seem to handle it just fine,” Moore notes.

Whales comes up to breathe.Giphy

Unlike Aquaman, when a person “breathes” water (that is, gets closer and closer to drowning), they’ll either cough up the water or swallow it as it enters their airways. The body really doesn’t want water to enter your lungs, so if water involuntarily enters the larynx or trachea, the body reflexively undergoes laryngospasm, a constriction of the vocal cords meant to prevent water from entering the lungs. When this happens during the initial phase of drowning, water is diverted into the stomach, not the lungs, which is why resuscitation sometimes makes people spontaneously vomit the water they’ve swallowed.

That explanation is a little bit closer to the Aquaman water vomit situation.

If Wan really wanted to make Aquaman’s water-to-air transition scientifically accurate, he would have made the hero more like a crab. Sure, crabs aren’t cool, but puking water isn’t cool either. The reason crabs can breathe in aquatic and terrestrial environments is because they have gills; in water, gills remove oxygen from the sea, and on land, they help diffuse oxygen from the atmosphere via moisture on the gills, so it’s important they remain damp.

Of course, gills would make a superhero about ten percent less sexy, but since we’re dealing with Momoa here, he can handle it.