Lately, I’ve been thinking a lot about octopi. I say this without a hint of irony. The octopus is a deeply weird creature. There’s a strong tradition in fiction that if you need to portray an alien as intelligent but completely nonhuman, you make it look cephalopodan:
"The peculiar V-shaped mouth with its pointed upper lip, the absence of brow ridges, the absence of a chin beneath the wedgelike lower lip, the incessant quivering of this mouth, the Gorgon groups of tentacles, the tumultuous breathing of the lungs in a strange atmosphere, the evident heaviness and painfulness of movement due to the greater gravitational energy of the earth--above all, the extraordinary intensity of the immense eyes--were at once vital, intense, inhuman, crippled and monstrous."
"Take evasive action! Green group, stick close to holding section MV-7!"
"The Beast and his armies will rise from the pit to make war against God."
"I'm sorry?"
"Apologies. I said: I hope you enjoy your meal."
I suppose it’s no real surprise. From the perspective of a terrestrial mammal, octopi almost as foreign as aliens might be, for a couple good reasons. For one thing, they inhabit a world completely different than ours, where the buoyant quality of water eliminates the need for a firm body structure that’s so ubiquitous to terrestrial animals. They are also the most evolutionary distant group of comparable complexity from humans. In fact, they’re more or less as distant as they could be while still being animals. The protostomes, the phylum containing octopi, snails, earthworms, crustaceans and insects (among many others), diverged from our phylum, the deuterosomes, so long ago that we’re closer related to sea stars than we are to octopi. Octopi, meanwhile, are closer related to butterflies than they are to us.
Aw, so cute. Oh dear god.
Octopi range in size from miniscule to bigger than you want to think about. Classic invertebrates, they have no bone; some have a sort of a vestigial cartilage shell inside their mantle, while other species are entirely soft and squishy except for a hard parrotlike beak. This lets them do mildly disturbing things like squeeze an eighty-pound body through a hole the size of your fist. They’re also very muscular. Each arm is usually stronger than a human’s - Though that depends on both the octopus and the human, I guess. There must be big buff octopi who go to the gym and obsess over ‘gains!’ and flabby nerdly octopi who write blogs instead. Even the nerdly ones can hobble about on land for short distances, looking quite silly but still standing up to gravity pretty well. They can carry large objects by squeezing them under their mantles and their tentacles are dextrous enough for crude manipulation.
But the thing I find really crazy about octopi is their brains. They’re geniuses, not only compared to other invertebrates but to most mammals – they’re smarter than dogs and might even be as smart as pigs. For a ‘lower’ order of animal, that is really bizarre. Octopi can learn to navigate mazes, distinguish between images, open jars and traps to get at food, and mimic their surroundings in some ways that will blow your mind. They can even use tools.
Some octopi gather coconut shell halves, carrying them at great personal risk until they get two halves they can use as a protective casing. The effortful, pre-planned act of gathering the shells constitues sophisticated tool usage. Whether they figure out that if you bang them together it sounds like a horse, we shall have to wait and see.
But it’s key to remember that evolutionary distance thing, because while octopus intellect may be comparable to mammalian intellect, it works completely differently. Dogs are really just very very stupid humans. You can look at a dog and have a pretty good idea what it’s thinking. You can’t do that with an octopus.
The octopus brain is actually smaller in proportion to its body that that of most mammals and birds, but it makes up for it with sheer complexity. It looks a bit like a pair of kidneys connected by a lot of string:
The kidneylike structures are optic centres, while the memory centres are distributed around the vertical and superior frontal lobes- the thing that looks like half a pumpkin and the surrounding area. I’m mostly ignoring the letter labels because they intimidate me. The spreading-out of memory is a trait we share; human memory is located all over the brain but primarily in the prefrontal cortex, the hippocampus and the cerebellum. Complex motor function (we’re back on octopus brains again) resides, as far as I can tell, in the small wedge just above the half-pumpkin.
Now here’s where it gets really weird. The processing power of an octopus is not entirely located in its brain – it quite literally thinks with its arms, thanks to a bundle of nervous tissue in each limb that controls all the complex motions of that limb, relatively independent of the central brain. So yeah, nine brains, of a sort. Before you get totally creeped out, I’ll try to orient you with a human comparison.
Psychology time! You know the phrase ‘gut feeling’? According to the somatic marker hypothesis, which has a lot of support, it’s actually quite an accurate saying. Nervous centres throughout the body and especially in the gut seem to initiate physical reactions to stimulus that inform our brains, rather than the other way around. And I’m talking complex, subjective things here, like disgust, mistrust and anxiety. People with damaged ventral pathways in the prefrontal cortex have trouble receiving and interpreting these somatic signals, even though all their cognitive function may be intact. As a result, you get perfectly intelligent people who make countless bad decisions because they can’t rely on the body cues that we might call ‘instinct’. Researchers had their subjects ‘gamble’ by picking cards from two decks, one that tended to afford small cash wins and one that gave the occasional big win and many large losses. People with normal prefrontal cortices started to sweat every time they chose the ‘danger’ deck and soon stopped picking it. Subjects with prefrontal cortex damage sweated in the same way but kept taking from the danger deck anyway. So yes, some of our decision-making actually happens in our bodies.
Octopi turn that all the way up to eleven. The brainlike nerve bundles in their arms receive signals from the central brain, but don’t seem to relay things back, instead using their own processing capacity to act out orders all by their lonesome. The octopus sees the prey and the brain tells the arm to go get the prey, but the mechanics and details of actually getting the prey are entirely up to the arm. Picture having an employee, telling him to do things, and never hearing back about whether they got done. In fact, the octopus seems to have so little sense of his arms that it doesn’t actually know where they are or what they’re doing except by looking at them. Imagine that for a second. Baffled yet? Good. It explains that clumsy searching quality in tentacle movements; though each tentacle is extremely flexible, strong and sensitive to surfaces (they even contain chemoreceptors that let them taste what they’re touching), each one is also a lost blind child who’s been told to get dinner but not where or how.
Then there’s camouflage. Octopi are second only to their cousins the cuttlefish in terms of blending into backgrounds, and they’re better than anybody at manipulating their bodies to look things other than octopi thanks to their flexible body plan. Their skin contains layers of pigment cells that respond to electrical signals by reflecting or absorbing light in response to visual cues: chromatophores (red, yellow, brown), iridophores (iridescent blues and greens) and leucophores (white – think leuko as in leukocyte or white blood cell).
Halfway through a colour change.
The very poisonous blue-ringed octopus. Bright colours: nature's way of saying 'Fuck thee not with me, for I am one bad motherfucker.'
Now, do we know enough to start talking about octopus consciousness? Octopi are not at all social but still demonstrate signs of being able to recognize other octopi by memory and even learn by observation (I know lots of humans who can’t do that). Two ‘stranger’ octopi will investigate each other curiously, but once they know each other they leave each other completely alone. They have sophisticated sensory systems but very little feedback from them, and they’re hard-wired to do whatever they can not to differentiate themselves from their surroundings. To me, what all this suggests is a sense of undefined boundaries and perhaps a lack of self. I’ve long suspected that social animals have a stronger sense of self than non-social ones. Could you define yourself as an ‘I’ without a ‘we’ or a ‘them’ to compare yourself to? Would you define yourself as you do if you weren’t constantly comparing yourself to others? The octopus recognizes other individuals in what seems like the same way it might recognize any other potentially dangerous part of the landscape. Then there’s the arms and their limited communication with the brain – in what sense do they actually ‘belong’ to the same consciousness that lives in the brain? Would an octopus define them as part of itself?
Clearly someone needs to write a book from the perspective of an octopus. There is an untapped well of mindfuckery to be had there. Perhaps in its own eyes an octopus is a centre of concentrated consciousness, from which the self diffuses outward along the path of its arms into nothingness. They would make natural Monists.
How strange to be an octopus
With each limb as its own
with arms unfurled to wander thus
In lands unseen, unknown
How odd to be an octopus
To fan each hand against the tide
And think not ‘I’ but rather ‘us’
And mantle nothing else inside
No secrets or illusions
hid within your golden eyes
A squishy self that bends and yields
and yet is strangely wise
For more cephalopod facts, visit the wonderful blog Cephalove, whose cogent explanation of octopus neurology I stole and then butchered. And lots of other people who make their livelihoods investigating these lovely freaks. Lucky bastards.
