This is an update and repost of our seminal article on the science of Aquaman, revised and expanded.
Aquaman may not be everybody’s favorite superhero, but since his creation in 1941, he has been among DC’s most enduring icons. During the Golden Age of comics, he held his own against Superman, Batman, and Wonder Woman. Silver Age Aquaman was a founding member and eventually leader of the Justice League. His powers, tied to the ocean, forced writers to create a compelling, complex hero with explicit limitations. In the early days, when Superman’s strength was practically infinite, and Batman’s brilliance was unmatched, Aquaman had to become more than just a superhero, he had to be a person.
If Superman existed to show us how high the human spirit could fly, and Batman to show us the darkness within even our most noble, Aquaman is here to show us the world that triumphs in our absence. The ocean is not ours, and no matter how great our technology, we will never master it as we have mastered land. Aquaman has. Through this lonely ocean wanderer, we can experience a world that we can never truly command. In many ways, Aquaman was stronger than the Man of Steel and darker than the Dark Knight. He knew loneliness that the orphan and the alien exile never could.
Even though Aquaman had to fight harder, endure the jokes of other, less interesting heroes, and find relevance in an ecosystem hostile to the humans that had to empathize with him, Aquaman was never forced to confront the truly horrifying consequences of life in the ocean.
The penetrating cold
Aquaman is, for all intents and purposes, a marine mammal. With the exception of a healthy mane in later incarnations, he is effectively hairless. As a human, we would expect his internal body temperature to hover around 99°F, or about 37°C. Even at its warmest points, the surface temperature of the ocean around the equator is only about 80°F/27°C. At the poles, ocean temperature can actually drop a few degrees below freezing. In the deep sea, ambient temperature levels out around 2 to 4°C. The ocean is cold, and water is a much better thermal conductor than air. Warm blooded species have evolved many different systems to manage these gradients, including countercurrent heat exchangers, insulating fur, and heavy layers of blubber. This is what a marine mammal that can handle cold waters look like:
Aquaman is not just a human, he is an atypically uninsulated human. If the man has more than 2% body fat, I’d be shocked. In contrast, warm-water bottlenose dolphins have at least 18 to 20% body fat. Anyone who SCUBA dives knows that, even with a 12 millimeter neoprene wet suit, after a few hours in 80°F water, you get cold. Aquaman, lacking any visible insulation, should have slipped into hypothermia sometime early in More Fun Comics #73. He is built for the beach rather than the frigid deep.