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Sea Monsters Exist: Coelacanths, Giant Squid, and ...?

Fossil fish and sea monsters exist!

 

sea monsters exist

People used to think coelacanths were extinct. Before 1938, these primitive deep-sea fish were only known through the fossil record. Biologists and paleontologists of the day believed at least 90 different species of these scaly beasts became extinct 65 million years ago. We attributed their mass extinction to the same event that killed the dinosaurs.

But we were wrong. 

Per the Smithsonian, the first living coelacanth (later named Latimeria chalumnae, after its founder Miss Marjorie Courtenay-Latimer) was discovered in 1938 off the coast of South Africa and was described by Professor J.L.B. Smith in 1939.

While Latimeria is distinct from the fossilized fish, you can recognize all coelacanths by:

  • Their distinctive shape
  • A hinged skull that can flip open from the back
  • Lobed, leg-like fins

Those lobed fins make the fish a tetrapod. It can walk along the seafloor — and perhaps it could walk on dry land occasionally.

Coelacanths vary in size. But the largest ones are nearly seven feet long. And they prefer to live in the deepest ocean waters, miles below the surface.

We were shocked and delighted to find these prehistoric-looking life forms! They're nearly identical to those which once stalked both marine and freshwater environments 100 million years ago. And for a long time, people only found these living fossils in the Indian Ocean. 

In 1997 and 1998, We Found More

Fast-forward sixty years, and scoot 6,000 miles east to Indonesia. That's where Mark V. Erdmann, a doctoral student at UC Berkeley, found another species of coelacanth.

At a glance, the Indonesian fish superficially resemble those in the Indian Ocean. But DNA analysis revealed significant genetic differences; we won't get into them here for the sake of brevity. Still, people believe these two populations separated several million years ago, at least. 

They're Still Very Rare

People have collected only a few coelacanths. They're usually a byproduct of commercial shark fishing because they get caught in deep gillnets and hauled to the surface. (Shark finning, by the way, is a dirty business and an environmental topic worthy of an entire article. We'll save it for another day, but we aren't ignoring it.)

African Fishing Tribes Knew About Coelacanths

Stories and rumors among Africa's coastal fishing tribes describe coelacanths as being caught in fishing nets occasionally but returned to the sea. They're simply too big and too ugly to bring back to the market. "Why drag that huge ugly thing home if no one will buy it?" We tend to believe these stories because literacy in sub-Saharan fishing communities is minimal. 

We envy that in a romantic way. Imagine a simple youth spent fishing on the ocean every day rather than in school. It sounds like a fantastic lifestyle until you realize a poor catch means no supper.

But we digress.

The point is that these life-long anglers probably don't read science journals in their downtime. If they can describe a coelacanth — with fins like legs and a head that flips open the wrong way — they probably saw it. 

Seeing Is Believing

The human mind can create all sorts of terrifying beasts stalking us beyond the light of the campfire or swimming in the darkest depths of the sea. But some stories are too common, among all cultures, for us to ignore them.

Giant squid, for instance, might be the inspiration for ancient tales of the Kraken. But we didn't have solid proof of them until 2006.

Before that, we thought of them as fanciful stories of mythical sea monsters from drunk sailors. Perhaps sailors merely embellished the tales, we thought, for the lost fish in such accounts always seem to get bigger with the telling. Yet Herman Melville felt they were believable enough to include them in Moby Dick, published in 1851.

"The great live squid, which, they say, few whale-ships ever beheld, and returned to their ports to tell of it." Captain Ahab, Moby Dick.

Giant Squid Do Exist

Fishermen battle with the giant squid - scanned 1881 engraving

The Smithsonian says it best: the giant squid lives up to its name.

So far, the largest specimen recorded was almost 43 feet long and weighed nearly a ton. Its circumference was 1.7 meters or about five feet. If you were to fry up that squid for calamari, the rings would be like hula-hoops!

Such a huge — and somewhat disgusting — creature is hard to miss. But oceans are vast and deep. Giant squid live deep below the surface, and they travel quickly. So they remain elusive. Most of what we know comes from dead carcasses that float to the surface and scraps of giant squid tentacles that occasionally wash ashore. (More on that in a moment.)

How Big Are These Sea Monsters?

It's hard to say definitively. We continue to learn what we can from the scraps that come ashore. Tentacles can fall off when a squid is attacked (by something even bigger, like a whale).

Dead, rotting tentacles can become stretched or bloated, so marine biologists use mantle length to best measure a squid's size. The mantle is the muscular portion of the squid, where its vital organs are.

So far, the longest mantle recorded is 7.4 feet. And the longest total length — including possibly stretched tentacles — of a giant squid is 43 feet.

A new method for estimating squid size uses the beak to estimate total body length. This is helpful; people find the hard beaks of giant squid in the bellies of sperm whales. Based on this formula, experts believe a giant squid could reach lengths of 66 feet. But we haven't found a whole one that big. 

Now, let's think about the creatures that eat a giant squid.

There's Always a Bigger Fish

We know that sperm whales eat giant squid. There's undeniable empirical evidence: giant squid beaks in sperm whale bellies that have been killed to appease the appetite for whale meat in Asia.

We know giant squid are predators. But they also have a lot of muscle tissue: rubbery meat that's not guarded by venomous barbs, tough scales, or a hard shell. Their body shape suggests they're swift in the water like other squid species, but they're the perfect dinner for something huge and very fast.

And there's always a bigger fish

Do Real Sea Monsters Exist?

They could exist because they have existed. We have proof of enormous megalodon sharks that lived in prehistory. It's possible that, like coelacanths, some gigantic shark species still lurk in the deep, unbeknownst to us. Miles beneath the surface, these toothy beasts would make quick work of a giant squid. 

  • The megalodon wasn't the only enormous sea monster in the ocean.
  • An extra-large whale species, Leviathan melvillei, swam about seas near Peru at the same time.

Then there are anecdotal and circumstantial pieces of evidence to consider, like old nautical charts and maps.

Ancient Nautical Maps and Charts Often Include Them

For almost a millennium, cartographers (mapmakers) included depictions of sea monsters on their maps. Were these always a point of decoration? We believe there could be something more to those little details than an entertaining tidbit.

After all, a well-drawn, half-naked mermaid would be far more entertaining to a captain at sea for months than a make-believe sea serpent. Which map would be prized more: the one with a good location of genuine danger or the one with exceptional breasts?

We believe cartographers depicted those monsters at a precise point to indicate a reported sea monster. Also, interestingly, many seafaring cultures included them in their oral traditions. The Scandinavian sailors had their Kraken, and the Chinese seafarers had a host of enormous dragons and sea turtles.

No discussion of sea monsters could be complete without the very modern Loch Ness Monster, "Nessie."

Could Nessie Be Real? (Spoiler, probably not, right now.)

Modern marine biologists believe the likelihood of a giant freshwater beast living in Scotland's Loch Ness to be minimal. Most of the evidence we see today is an entertaining hoax made to boost tourism.

But ancient stone drawings, done by the tribal Picts, illustrate a dinosaur-like creature there, complete with a long neck and flippers. That's the sort of thing you would only believe if you saw it.

Then again, it's not like the early tribes of Picts read scientific journals! If you saw Nessie but couldn't read or write, it would be worth carving into stone to warn others.

But still, from what we know of biology, it would be difficult for a giant dinosaur-like creature to live in Loch Ness full time. The water is too cold to support a cold-blooded creature of that size. Also, to maintain its body heat in such cold waters, a warm-blooded animal would need to eat a lot of, well, something, like giant squid or kelp beds found in saltwater.

Ultimately, it's best to remember that our oceans are vast and mysterious still! The National Oceanic and Atmospheric Administration (NOAA) says more than 80% of them remain unmapped, unobserved, and unexplored. There's no telling what's swimming out there under the surface.

AMNH.org: Sea Monsters

Conservation.org: Fish Story: How a Coelacanth Discovery Set Off a Flurry of Science, Subterfuge

Newworldencyclopedia.org: Giant Squid

Amazon.com: The Sea Chart: The Illustrated History of Nautical Maps and Navigational Charts