So it turns out octopuses will never rule the earth.

Wow, here’s one of those science articles in The Atlantic–“Octopuses Do Something Really Strange To Their Genes” by the excellent science writer Ed Yong–that demand a full reading because every paragraph is a cephalopodic mind freak. Turns out that cephalopods have an extraordinary ability to edit their own nervous system genes in a massive way. The astonishing nervous systems and intelligence of the octopus has been created by editing the RNA, as if humans could go in and edit our own DNA to make us smarter, say. Which we can’t. Hence Trump.

The downside of this is that in order to this, cephalopods have to maintain the integrity of their RNA…and I mean maintain it over hundreds of millions of years. So their nervous systems have evolved to incredible degrees–human brains are much more intelligent than any cephalopod, obviously, but the other parts of our nervous system are infinitely less so–we can’t disappear into our surroundings, say, or communicate via rapidly changing colors in what is probably language, or control eight limbs that operate autonomously from one another. But if you carefully edit your RNA to dispose of any unwanted mutations you are essentially putting a brake on natural selection, that is, you are not letting evolution make the changes that alter the genome and create new species out of older species. Humans are the result of series of changes in genomes from apes twenty of thirty million years ago that went into overdrive about four million years ago. The Australopithecenes four million years ago were basically bipedal chimpanzees. Two million years later was Homo erectus , every inch a human. We showed up 200,000 years ago, though none of us today are exactly the same as we were then. We have not stopped evolving (our brains are larger, for one thing, and structured a bit differently). And we are still apes, just dramatically transformed by an extraordinary number of mutations. Our genome has changed fundamentally over and over, and you can even see that process at work around you. In me, for instance. I’m way taller than most people, everything bigger. I’m full of mutations. I could have eventually led to a sub species of really huge, really dumb homo sapiens–homo sapien brickus–and ruined everything. Luckily I had no kids.

But this can’t happen among cephalopods. Well, among coleoid cephalopods, the smart ones, that is octopus, squid and cuttlefish. Nautilus never made that adaptation–this may have been nearly half a billion years ago–and so never developed the ability to edit their own RNA. And while an ocean existence makes for far less evolutionary change over vast expanses of time than a land existence (the ocean changes very little, and is much safer) so that the nautilus today looks remarkably similar to the nautilus in 400 million year old fossil beds–natural selection at some point extended its lifespan to twenty years. That is a very good age for a mollusc (cephalopods are molluscs.). That was about how long our own early ancestors, australopithecines like Lucy, lived. Nautiluses have unedited naturally occurring mutations in their genes, and while Nautilus lives are so stable and unchanging there is little chance for any of those mutations to succeed as new species, it has lengthened their life span because living longer is apparently useful (or not unuseful, anyway). And that was a very fundamental change in the nautilus genome. Three hundred million years ago they probably lived no longer than an octopus, two years. The genome was fundamentally altered. Probably very slowly, over tens if not hundreds of million of years, but it was altered, and now a pet nautilus would live longer than your cat.

Your pet hamster would outlive your pet octopus, though. Would outlive virtually every coleoid cephalopod (that is, all the cephalopods but the nautilus). For at least 350 and perhaps as much as 480 million years the octopus has carefully maintained the vast number of edits in its RNA, because their extraordinary nervous system is based upon the integrity of that design, just as the computer you are reading this on can only function if the memory maintains the integrity of its design–go in their and randomly mutate the thing, moving chips around, deleting some, adding others, and you’ll be looking at a blank blue screen. The cephalopod nervous system, perhaps as extraordinary a work of nature as our own, is a delicate construct, built by billions of generations of cephalopods carefully maintaining the original RNA structure and making myriad new carefully selected edits. It’s like they’ve been speaking the same language for half a billion years with the same basic grammar, so that one could pick up a book written hundreds of millions of years ago and be able to read it still. It would be less changed than English now has changed from English a thousand years ago. There is a continuum in octopus RNA across deep time. Nothing has fundamentally changed, Roman Latin didn’t turn into Chinese. The same basic design has remained for half a billion years, just fine tuned to an amazing degree. Which means you can never have a giant six legged octopus attacking ships and tearing the Golden Gate bridge apart. You would need to have a genome that can change dramatically with unedited RNA allowing for mutation. Nor could ever have them leaving the water and becoming land animals. Or shedding limbs and walking about. Or flying starships and colonizing other planets. You can’t even change the octopus genome to let them live longer than two years.

So you have extremely intelligent invertebrates–smarter than probably 99% of vertebrates–trapped in bodies that, like some ancient, primitive molluscs of the Cambrian Era, live a couple years, lay a zillion eggs, fertilize them, and die. You can fine tune your nervous system till you are an eight legged Einstein but you can’t alter that ancient method of self-destructive reproduction. So you have invertebrate geniuses trapped in bodies designed for no brains at all. Octopuses will never rule the earth. They’ll live an astonishing two years–some only six months–and die. Squids live a year. Even giant squid live less than five years. (Their vertebrate arch enemy, the sperm whale, lives to be seventy.)  And so “Octopuses Do Something Really Strange To Their Genes” was one of the most exciting articles I ever read, and one of the saddest.

However…recently a deep sea Graneledone boreopacifica was observed guarding its brood for an astonishing fifty three months (the longest brood time ever witnessed in the animal kingdom)…which is over twice as long as the typical longer lived octopus lifespan (some live as little as six months). A female octopus spends about one fourth of her life brooding and then dies (of starvation) and if that ratio holds, the Graneledone boreopacifica could live as long as twenty years….or about the length of a nautilus life span. Somebody let some mutations slip through, apparently. Perhaps there’s no reason an octopus can’t live as long as a nautilus. An incredibly smart nautilus at that. Of course, that depends on whether those mutations don’t unravel that beautifully maintained matrix of RNA edits that goes back half a billion years upon which the extraordinary sophistication of the coleoid nervous system is dependent. But a problem solving, tool using octopus could do quite a bit in a twenty year life span. Maybe in a hundred million years we’ll know. Well, we won’t. We’re terrestrial animals, and mammals, and primates, and humanoid. Ours is a tough neighborhood. All the various human species have had a million years or two and then gone extinct. It’s a rough world out here on land.

https://www.theatlantic.com/science/archive/2017/04/octopuses-do-something-really-strange-to-their-genes/522024/

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