When I Grew a Backbone, Story of The Samurai Mudskipper

Mike Levin, an old warrior, tells his child a story about the evolution of the backbone. He explains that the backbone developed over a long period of time, beginning with single-celled organisms and ending with the Cambrian Explosion. Mike then tells his child that he can grow a backbone and map out the life of a single being, starting with the present. With this story, Mike hopes to prepare his child for the predators of the future.

Growing a Backbone: An Old Warrior's Story to Prepare His Child for the Future

By Michael Levin

Monday, May 16, 2022

Backbones aren’t born overnight my child.
They take some time to evolve.
But how long? Asks the curious child.
Well, let’s see. First we must set the overall time-frame.

We measure time, and really all things, in 10 times 10 units.

Ten times ten is a hundred.
A hundred times ten is a thousand.
A thousand times ten is ten-thousand. That’s ancient Egypt.
Ten-thousand times ten is a hundred thousand. That’s cave people.
A hundred thousand times ten is a million. That’s monkeys splitting from people.
A million times ten is ten-million. That’s the rise of primate ape things.
Ten-million times ten is a hundred-million. Single-cells colonize into proto-animals.
- Backbones come into the picture somewhere around here, but let’s keep going.
A hundred-million times ten is a billion. Life is slime-mold here on Earth.
A billion times ten is ten-billion. There is no Earth and the Universe is young.
Ten-billion times ten is a hundred-billion. Let’s look forward in time, instead.
A hundred-billion times ten is a trillion. I’m told there is a restaurant here.

This is where the expression “Crank it up to 11” comes from. Otto the bus driver from The Simpsons can confirm this fact.

So it’s only around step #7 during what’s known as the Cambrian Explosion of different blue-prints, templates or experimental life designs that creatures started protecting spinal cords with a foamy form of common rusted metal accidentally ingested while eating, known as calcium. Things started getting rigid on the inside.

Honestly, first you only get a single vertebra. It’s not really a fully formed backbone yet. That’s about where I am too.

Wishy-washy creatures started becoming firm

There was some risk here. During this wacky experimental Cambrian explosion, more than just calcium was scavenged for rigidity. An even more common easily-rigid material was available called silicon. But when you knit silicon into bones, you’ve got glass bones that are easily shattered.

Many creatures that evolved during the Cambrian period unfortunately died this way. Even though they made lots of neat stuff like swords and shields, every time they faced a competent opponent who could really pack a wallop, those silicon-based weapons and shields shattered.

This is where the expression “glass jaw” comes from, which can be confirmed by both SpongeBob and Batman if you were to inquire about Tony Zucco and Flats the Flounder. Think, McFly. Think!

Calcium was used for both shields and weapons like silicon, but it turns out that chalky white rusty metal is much better than glass for such things, so it stuck. Some of the creatures who wore it on the outside survived from Cambrian to the Ordovician Period in such as trilobites and proto-crabs.

But some rare and odd fellows that were rather worm-like in appearance found the nerve to try something new.

Wear it on the inside.

Keep it close.

Have a secret weapon.

Pull it out when you need it, perchance to stab.

Or even to bite… bite like as if with a… hmmm… jaw?

The First Jaw Was a Switch-Vertablade

Child: “Wait, that’s crazy, Dad!”

Mike Levin: “That’s right, child. I’m saying that the evolution of the first jaw was as a surprise secret stabby-weapon, and this directly led to having a backbone.”

For you see back in those days, the mouth and the top of what we call the spinal cord were not very far apart. There were no eyes. It was just a light-sensor at the top of a nerve cell.

And so it’s not a long stretch to imagine that the first proto-jaw was the exact same thing as the first proto-vertebrae.

It’s debated, but so what? This is my story and I tell it how I like.

And that same rigid ring of stabby-material that let worms bite’cha is also what made them able to survive as your great-great-great-grand-something and continue your family-tree onto today.

Without a switchblade-wielding worm, you wouldn’t be here–or at least, not with any backbone to speak of.

That rigid ring of jaw-material split in two, one sliding up for biting, and the other sliding down to become your spinal-cord protection like the continental drift that split Pangea. Of course, there was no spine yet, so they didn’t know to call it that.

So getting a backbone starts with biting, you see.

Chomp, chomp, chomp!

Child: “So do you have a backbone yet, Daddy?”

Mike Levin: “Soon, my child, soon. Let me finish the story.”

Sooner or later you got eels up inside ya, finding an entrance where they can. Yuck, right? I know! But just like less noble predators took up ambush strategies as a sort of loophole to conserve energy while taking potshots at victims, these ring-toothed worms slithered up inside of you, boring a meat-hole and their ticket to a meal.

As you might expect and hope from one of your ancestors who had to take up such horrible strategies to survive during this fierce time, they felt great self-hatred at what they’ve become. Such a simple and useful switchblade-jaw becomes a bloody butchering tool. Were they no better than the ambush predators they fear?

No, of course they were better than that! And they set out to prove it. These now now lobe-finned fish realized that there must find another way.

Time to evolve.

Muddy the Mudskipper is Born

Find more fertile hunting (and breeding) grounds free from those lecherous sharks.

Child: “But aren’t we the leaches?”

Mike Levin: “Quiet, kid. I’m telling a story.”

Okay, so the lobe-finned fish eventually evolved themselves into mud-skippers that could waddle and claw their way onto land where there was more things to eat and less things to eat them.

Cowards? Maybe. But they are your ancestors, so be polite!

Of course many still-eel-like things stayed in the water and became fish of all sorts. They’re more like cousins. But you do have an inner-fish, mind you. It’s your pituitary gland at the top of your spinal-cord, the first protector of your nerves.

The fact is that you’ve got some nerve.

You’ve got some nerve because of this mudskipper who can bite.

If you lose your nerves at that point, you’re dead, even in this brave new world of land, skin-drying sun and infernally stronger gravity.

But you know what? I can live with it, said Muddy. This ain’t so bad. I am a dynamic creature equipped with this cool secret biting-weapons and this shield around my nerves.

It can fight the gravity!

It can turn flippers to feet.

In and out of the water it goes. Little by little, Ni Hao, Kai-Lan!

And so spinal-cords were born. Scientists put it at about 550 million years ago. That’s just over a half-billion, and so is just half-way back through all time, if on your scale each unit is an order-of-magnitude larger than the previous.

Count to a Trillion By Tens in Seconds

See? You can just draw a line with ten equal subdivisions. That’s the whole age of our known Universe. Each step along that line is times ten larger (or smaller, depending on which way you decide time flows) than the previous. Such scales using order of magnitude steps are called logarithmic scales.

It’s only by convention because we have ten fingers that a logarithmic scale’s order-of-magnitude steps are times ten. Beings who had six or eight fingers would probably think our logarithms are weird. And maybe they are. But it’s convenient for counting, because you know, ten fingers.

So the answer to your question is just a bit over half-way back in time, around 7 on a scale of 10 to 10, in the age of our known universe on a logarithmic scale is when my ancestors first grew a backbone.

Honestly though, kid, I’m still working on it myself, for you see I’ve been afraid to bite.

Cornered By The Kid & A Promise Made

Child: “But why, Daddy? You’ve got such sharp teeth and you tell me about your secret weapons all the time. I’m starting to not believe you.”

Mike Levin: [Can’t even read the above line without choking up]

I know, I know little one. Sometimes an old seasoned warrior who has needed to use those weapons a little too often in life gets tired. A sleepiness settles over them, and it is a time to rest. It is a sort of drunken stupor of a warrior. It is all of the warrior’s own doing. There is no fault or blame being doled out. One lives with the consequences of ones decisions, and having regrets is stupid.

You have had the special circumstance of being born during my tired.

Things are precisely as they should be. I hold it in my heart that you actually needed to feel the bite of a predator in small doses in order to prepare you to prevail against much worse predators in the future. This I feel gives you a deeper understanding of and appreciation for your existence as the descendent of the toothy-jawed-worm, so overflowing with evolutionary creativity as it was.

And so now I awake from my stupor. A slumber that resembles regression to a time before jaws. To a time before backbones.

But with the return of the vertebrae comes first stories. Stories, then strength. Strength, then action. Action, then life.

Life as you deserve it. Life as you may know it. Life that is your birthright in the great, long linage of noble leaches turned Samurai mudskippers.

Child: “Daddy, I feel in danger. Without knowing precisely what or how to fight, I strike back when feeling prodded and probed and pecked-at by predators. This leads me to feel anxious and striking back in ways that make me look like the predator. I am so afraid. I can’t believe in your secret weapons, I won’t believe in your secret weapons if you can’t show me.”

Mike Levin: “This breaks my heart little one. And okay. You are right. I am a dynamic being. And I can grow a backbone.”

It is time.

Let us begin.

For our next lesson, we will go through this same exercise again.

But this time we will mapping out the life of a single being, not in these billion-year steps, but within step #1 where time times ten is a hundred. Where are you now?

I am just ten, Daddy.

Okay then, that’s a perfect place to begin. Now what’s a hundred divided by ten?