Some fish have turned into dragons
As long as life thrives and genes replicate, one life form will become another.
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As long as life thrives and genes replicate, one life form will become another.
Dragons?
Admittedly, the image that comes to mind when we read dragon (a term that comes from Latin and Greek roots meaning giant serpent) is a mythical beast. And that's what most dragons are: works of fiction.
This is not to say that they are trivial since they have influenced many mythologies and common lore from past and present, as reflected in the plethora of novels and video games with giant fire-breathing lizards as a central theme. Many of us have even become The Dragonborn.
However, not all of them reside in folk tales.
Contemporary, real-life dragons
The mythical creatures of yore have also inspired biologists, and certain reptiles receive that name. That is the case, for example, of the Komodo dragon, Varanus komodoensis: a 150-pound sturdy species native to the Indonesian Komodo island that instill fear upon insects and rodents as younglings, while adult specimens can prey on deer, boar, and other Komodo dragons.
And even though their flesh-tearing bite is fearsome on its own merit, those bitten soon come to realize that there are delayed consequences of such an encounter. Their venom can potentially worsen an already ugly wound, with ensuing collapse within days. That is if the prey has not bled to death yet.
There have also been references to the debilitating effects of this lizard's mouth-dwelling bacteria, suggesting bite-induced sepsis could be a lethal contributor. This hypothesis, and the degree to which venom plays a role, have been the subject of debate and conflicting publications.
But not all real dragons are nightmare material. The bearded dragons (Pogona) are half a meter long, feast on plants and insects, and can change the color and shape of their throats in response to many environmental and social stimuli. They are often kept as pets, harmless and cute, though not as cuddly as our more popular mammal companions.
Now don't think this cheerful-looking buddies fall far from their Indonesian cousins. Bearded dragons (like Gila monsters, Komodo dragons and some snakes) are venomous too. It's just that their venom is mild and does not represent a threat to you.
Dragons that were fish
Life on Earth began in the oceans, and fish were there first before all the remaining vertebrates entered the scene.
Not only do these dragons have an ocean-dwelling ancestor with gills and a bony or cartilaginous skeleton, but all reptiles. In fact, all amphibians, birds, and mammals (including you and me) also have distant fish relatives.
In this progression, and based on protein sequence data and molecular clock methods, evolutionary biologists estimate that the first fishes-to-be whose cell lines split from their arthropods predecessors did so about 974 million years ago, during the Tonian period of the Neoproterozoic era. These first fish were agnathans, which means they did not have a jaw, an innovation that came later in the game of evolution when a fish got tired of the sucker life and chose to chew.
And though most current fish have a clear mandible, some species of agnathans related to those first-ever vertebrates are still present in our biosphere. This is the case of lampreys and hagfish.
In a completely different eon, more modern fish saw the amphibians' predecessors separate. This occurred around 450 million years ago, during the Ordovician period of the Paleozoic era. Just picture those first brave, slimy creatures who dared expose their skin to air and derive the necessary oxygen from it, just before uttering a mighty ribbit.
Finally, reptiles split from amphibians about 360 million years ago, at the end of the Devonian period of the same era. Here, vertebrates clearly stated that we were done with living in the ocean, never ever to come back. That is, until a melancholy-ridden wolf/fox-like animal, after a period of happily foraging in streams and eating fish but sleeping on land, one day took a definite plunge back into the water eventually giving birth to past and present whales and dolphins.
Others have since decided to go back, ride the tides, and eliminate a portion of gravity's apparent pull and demands. Ever seen a stranded whale? Yeah, firm soil is no longer their element.
Wasn't this about dragons?
Returning to the subject: We know life began in the ocean and that all modern vertebrates come from fish. We have also agreed that some dragons do exist. But why does the image of a fish becoming this specific creature seem familiar?
It may have to do with the Japanese tradition of the carp streamers and the Chinese Longmen.
The Carp Streamers
Koinobori (the Japanese name for these items) are beautiful decorations and just as wonderful for the meaning and tradition behind them.
Its Japanese name comes from two words: Koi, meaning carp, and Nobori, flag or banner. They are a kind of windsock, dating to the 18th century in Japan, but have predecessors earlier in the Edo period (1603–1867).
Similar to the wind socks you've probably seen in airports, conveying both the direction and speed of the current wind gusts, these streamers catch the breezes and swim in the air currents making for a gorgeous display.
Originally, samurai households would decorate their living quarters with family crest-bearing banners, while modern and more colorful koinobori resembling those currently on display made it into the popular scene during the Meiji era, in what now is Tokyo. At first associated with the family sons, these came to represent all family members in 1948, when May 5th was designated Children's Day (Kodomo-no-hi), celebrating their good health and happiness.
The complete display would feature a pole crowned with two spoked wheels and a spherical spinning element (the yaguruma), with a colorful topmost streamer (the fukinagashi displaying a family crest), a black koinobori representing the father followed by a red one representing the mother. Additional streamers would denote the household children.
The ongoing evolution of these traditional symbols has seen considerable modifications, even displaying large groups horizontally during outdoor events.
The Longmen
Japanese streamers featuring mighty carp draw from the Chinese legend of a strong and persistent fish that could conquer a waterfall. Specifically, The Dragon Gate at the top of a legendary mountain.
According to folklore, while many fish can swim upstream against the Yellow River's strong current, only a select few can make the final leap over the waterfall and those who do transform into dragons. The mythical beast represents benevolence and mighty magic.
An expression derived from the myth and its origins used to symbolize the significance of passing difficult imperial examinations, but its use widened to emphasize how diligent work can foster success.
Carps streamers and Longmen in pop culture
Being such entrenched (and beautiful) cultural items, it isn't surprising to see them spotlighted in popular culture. Ancient and current lithographs and paintings aside, here are a couple of examples.
There's an emoji for it, included since the first release of Unicode's documentation dating to 2015:
And there's a Pokémon character as well (could not miss this one):
As the official website describes, this is Magikarp, "an underpowered, pathetic Pokémon" weighing about 22 pounds.
But disregarding its awkwardness and pitiful semblance, it can evolve into a mighty... can you guess? Dragon.
Which is a quarter-ton monster named Gyarados who "once it appears, it goes on a rampage. It remains enraged until it demolishes everything around it."
Why a carp?
The tradition has to do with the resilience and determination this fish displays while swimming upstream, which is deemed a good example for the new generation. You better have a thick skin if you are a boy in a samurai household.
But beyond all praise for their vehement counter-current motion, now we understand that their strength goes beyond physical prowess: they have a remarkably powerful mind.
Did I say mind? I meant brain. A powerful brain.
Ok, so carps are mighty and genius even
No, no. Let me explain.
Our cells require more than fuel (like sugars and fats) for proper energy production; they also crave a comburent: oxygen.
However, not all animal cells are close enough to a blood vessel that can deliver unrestricted amounts of oxygen, so evolution provided them with an alternative way to obtain energy: anaerobic metabolism. This means they can retrieve some energy even in its absence.
But there's a catch: the usual outcome of anaerobic metabolism is lactate, which can accumulate, lower pH, and cause damage. Thus, not all cells are keen on this way to satisfy their demands; our highly specialized neurons avoid it at all costs.
Human brains, weighing only 3 pounds, constitute the most energy-demanding organs accounting for a fifth of total body oxygen consumption and a quarter of its glucose utilization. Lacking enough comburent, even for a few minutes, causes many critical processes to wreak havoc, altering our neurons' function and structure. Consequently, vertebrates can survive only the shortest of periods in a state of anoxia (very low to no available oxygen).
If you are a fish during winter, there are additional challenges: ice prevents water from acquiring atmospheric oxygen, and less sunlight penetrates the deep, which in turn prevents photosynthetic plants and algae from providing this element to their surroundings.
But carp are built differently, even within their skulls. They accumulate glycogen and can tolerate anoxic environments for months when the temperatures go low. But the key to survival is a catabolic feat allowing carp to perform another kind of oxygen-deprived metabolism: they ferment sugars.
Fermentation, a process carried out by many microorganisms, produces alcohol (ethanol) from sugar without needing oxygen-driven respiration. This microbial process supports the whole beer and wine industries, as well as a few of a baker's secrets.
Since carp are aquatic, the ethanol can freely diffuse to their surroundings without hindering their ability to drive or operate heavy machinery.
I don't know about you, but the idea of fish turning into dragons felt like a pretty cool way to begin this newsletter, and finding out about carp's astonishing brain-body endurance made me rethink how I look at goldfish in an aquarium.
They really seem like works of fiction.
That's it for today.
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