What If Humans Were Underwater Creatures? | Unveiled

What if Humans Were Underwater Creatures?

Humans are terrestrial animals, living on the land of every major continent, even for short periods of time on the cold and icy plains of Antarctica. But the vast majority of Earth’s surface is actually covered in water, and so many of those waters remain wholly unexplored by us. In an alternate world, that might’ve been very different.

This is Unveiled, and today we’re answering the extraordinary question; what if humans were underwater creatures?

The aquatic ape hypothesis is an anthropological theory that certain human traits, those which separate us from other primates, are the result of our species having had semi-aquatic lifestyles in the distant past. It was first proposed in the 1960s, and supporters of the theory argue that characteristics like our lung capacity and the fact we walk on two legs are evidence that humans were once a more aquatic creature. It’s said our ancient ancestors needed these specific adaptations so that they could wade into the sea, dive and catch shellfish, which meant they needn’t compete so much for food on land. It’s also put forward as a way to explain some of the potentially useful traits that humans don’t have; like our not having thick hair or fur to keep us warm in the winter, because that fur would’ve been disadvantageous in the water.

Though the aquatic ape hypothesis does have one glowing endorsement from the world-renowned documentarian Sir David Attenborough, it isn’t taken all that seriously by the majority of other scientists. This is because most believe that it just doesn’t hold up to deeper analysis, and that all of the human traits which supposedly support it are actually better explained in other, simpler ways. That our hairlessness, for example, is more likely linked to sexual selection or body temperature. Our apparently increased lung capacity and breath control compared to other primates is believed to be better linked with our ability to speak. And finally, our being bipedal just isn’t that unique… with plenty of other primates capable of walking on two legs if they choose, we’re just the only ones that do so constantly, most likely because it takes less energy to walk on two legs than on four. The other major criticism of the aquatic ape hypothesis is that we’re also not actually that good at swimming or diving - not compared to other aquatic and marine mammals, at least. And our senses - our abilities to see, hear, smell and touch - are also severely impaired while we’re underwater.

Whales and dolphins are intelligent, air-breathing mammals, much like us, but they’re obviously different to us because they’re built and evolutionarily designed to live their entire lives in the water. Humans, as we are, just can’t compare. The world record for the longest time a person has held their breath for is (an admittedly quite staggering) twenty-four minutes, but the average is significantly less. Contrast that with just the average for, say, sperm whales, and they can go around ninety minutes before needing to come up for air. The longest recorded time that any whale (and, indeed, any mammal) has held its breath for is 137 minutes. It’s not only true for whales and dolphins, though; animals like seals and otters also breathe air but can also comfortably hold their breath for ages. And seals and otters have fur, showing that our hairlessness is hardly a sure-fire sign that we’ve ever been a natural fit for water.

Perhaps the aquatic ape theory would be more widely supported if we had stronger, real-world adaptations to make us more like marine mammals… but we just don’t. It’s not the only way this alternate reality could play out, though. Many non-mammalian creatures get oxygen via gills instead of lungs, for example, and the aquatic humans from various myths and legends often have a similar setup. Merpeople folklore has existed for thousands of years, and the mermaids in the stories aren’t part whale or part seal, they’re part fish… with a fishtail and often gills. Familiar as these storied merpeople are to us, however, they’re a totally different prospect to the contentiously proposed aquatic apes of our own distant past. But, maybe there’s a middle ground. Some have theorized that something like the aquatic ape idea could in fact be part of our future. The diver and oceanographer Jacques Cousteau famously suggested that, one day, humans would take to the water and evolve into a new species; a species he called homo aquaticus. Perhaps we could view Cousteau’s future human as an amalgamation between aquatic ape and merperson… but what would a homo aquaticus society really be like? Would it be recognizably human at all?

Again, we can take our lead from the natural world that does already exist, as there are some sea creatures that already order their societies in similar ways to us. Whales travel in large, familial pods, they take care of their young for a long time, and it’s even been found that some have regional accents and dialects. If humans were underwater creatures, then, we’d still have our families around us, and we’d still have local communities and a hometown (or home bay). We probably wouldn’t have cities but, after a large community of octopuses was discovered off the coast of Australia in 2017 and dubbed “Octlantis”, there’s reason to believe we would still group together. The ocean is wide, but aquatic humans could still be social creatures.

In almost all other ways, though, we’d have to be totally different animals. It’s simply too difficult to accomplish many of the things that humans have on land, underwater. One of our most important tools, for example, fire, doesn’t fare well underwater - which means no cooking or developing complex metals to build with. But even if we had fire, the free physical movement we enjoy on land, the incredible dexterity in our hands which has enabled us to craft all kinds of things, from clothing to skyscrapers, would no longer be there. We’d have lost so much of that mobility because of the weight and density of the water - something which would only get worse the deeper we travelled. Octopuses and whales might be some of the most intelligent, non-primates on the planet, but they still don’t have hands and fingers… because they would never be able to use them. And that’s crucial. If humans lived underwater, we wouldn’t have hands and fingers, either.

Of course, being an underwater creature and living underwater aren’t necessarily the same thing. And humans, as we are, have made various efforts to build suitable, human-specific habitats under the waves. But, again, there have been problems. Building anything underwater has proven a puzzle down the years, but efforts were led by Jacques Cousteau, again, in the 1960s. Cousteau, who is arguably humanity’s greatest ever advocate for underwater living, helmed multiple projects to build human-inhabited villages under the sea. But, the remains of these ultimately abandoned villages, specifically Continental Shelf Station Two or “Conshelf Two”, can now be found definitely uninhabited at the bottom of the Red Sea. Conshelf Two is large, yellow, and bizarre looking - more like a spaceship than a submarine - but, for one whole month in 1963, six people (who were dubbed oceanauts) did live and work inside it. That’s really as far as we’ve got, though, with the few underwater bases that exist today still operating mostly as short-stay research labs rather than long-stay settlements. And, although Cousteau remained a believer that humans were destined for the sea, land-mimicking labs like these aren’t about to trigger in us any kind of evolutionary adaptations to turn us into a new, truly underwater species.

The reality is that if anything ever happened to force us into the water as we are now, any kind of disaster event, then humans would be in serious, almost certainly un-survivable trouble. If, in an alternate world, humans simply were underwater creatures, though… well, we’d look and behave drastically different to how we do now. If even parts of the aquatic ape hypothesis are true, then perhaps our fairly hair-free bodies wouldn’t change all that much… but we probably wouldn’t have hands, or feet, because we wouldn’t need them, because we wouldn’t be building things all the time. If we retained the need to breathe air, then we’d have had to have developed far superior lungs to what we have now. Or we’d need to have ditched air altogether and grown gills… in which case everything not covered in water - the mountains and valleys and cities - would be our great unknown instead. Where, as we are, the bottom of the sea is a place of infinite mystery, if humans were solely underwater creatures it would be the rocks and trees of dry land that would capture our imaginations most of all.