This is the third part of a longread of this book. If you’re looking for earlier parts, please refer to the first and second parts.
So far, we’ve covered the Cambian and we have discovered life has discovered predation, with the natural result of having a body that can either inflict or evade damage via the structure of a bilateral body, and we’ve begun to discuss the nature of a mind that processes what can be dangerous.
But let’s take a quick step back and observe, as it might be, of what brings about the creation of a response system, and in that way, actually being to embody what mind can be. This is highly theoretical, but the idea is nonetheless compelling.
Possibilities abound. Here is one developed by the biologist Detlev Arendt and his colleagues. As they see it, nervous systems originated twice. But they don’t mean that they evolved in two kinds of animals; rather, they originated twice in the same animals, at different places in the animal’s body. Imagine a jellyfish-like animal shaped like a dome, with a mouth underneath. One nervous system evolves on the top, and tracks light, but not as a guide to action. Instead it uses light to control bodily rhythms and regulate hormones. Another nervous system evolves to control movement, initially just the movement of the mouth.
And at some stage, the two systems begin to move within the body, coming into new relations with each other. Arendt sees this as one of the crucial events that took bilaterians forward in the Cambrian. A part of the body-controlling system moved up toward the top of the animal, where the light-sensitive system sat. This light-sensitive system, again, was only guiding chemical changes and cycles, not behavior. But the joining of the two nervous systems gave them a new role. What an amazing image: in a long evolutionary process, a motion-controlling brain marches up through your head to meet there some light-sensitive organs, which become eyes.
It makes intuitive sense: at some point, a sensation system met a motor control system and combine. Once a sense can lead to motor control, the presence of a signal can lead to a twitch, or some other form of motor control. Eventually, as processing of the input becomes more complex, as the neurons begin to communicate with each other, it forms the foundations for something like a “system of reactions” to happen, for something like directed behavior, and for something that we’d call a brain.
And along with vertebrates, it very much seems to have followed along a single path such that via convergent evolution, we can find very much a similar design even in creatures as far as birds from fish.
When biologists look at a bird, a mammal, even a fish, they are able to map many parts of one animal’s brain onto another’s. Vertebrate brains all have a common architecture.
But intelligence in invertebrates, on the other hand, can be very different. And so enters, finally, the main hero of the story, the octopus. Up to this point, we have been thinking of a brain in an animal – singular, as it might be, and usually in something morphologically familiar like a head.
But octopi have brains in their hands.
There is no part-by-part correspondence between the parts of their brains and ours. Indeed, octopuses have not even collected the majority of their neurons inside their brains; most of the neurons are found in their arms. Given all this, the way to work out how smart octopuses are is to look at what they can do.
This makes sense. After all, one of the basic definitions of intelligence is the ability to solve problems, challenges in the world for which the solutions if found would either advance the organism’s cause in the world or prevent a messy end usually inside the digestive organs of another.
But this, as it turns out, is more difficult with animals with such wildly alien, and different comprehensions of the world, as the story of an experiment with three octopi reveals themselves with – curious, mischievous and surprisingly destructive toward the laboratory environment.
Could they, for example, learn to pull a lever for food? Yes. But sometimes one will go beyond just that:
When they pulled the lever, a light came on and a small piece of sardine was given as a reward. Two of the octopuses, named Albert and Bertram, did this in a “reasonably consistent” manner, Dews said. The behavior of the third octopus, named Charles, was different. Though Charles did pass the test in a minimal way…Charles anchored several tentacles on the side of the tank and others around the lever and applied great force. The lever was bent a number of times, and on the 11th day was broken, leading to a premature termination of the experiment.
Charlie’s misadventures did not end there. While the other two octopuses behaved normally in respect to their interest in food, Charlie became fascinated with the light above the aquarium and repeatedly found himself capable of encircling the lamp above it with his tentacles and absconding with the light into the tank for no obvious reason.
He also proceeded to spend much of his time gazing with his eyes outside of the water, and would spray any individual who approached the tank with water, causing enough trouble that it was noted as “intervening materially with the smooth conduct of the experiments.”
This kind of unusual behavior would be noted in other experiments as well, where if nothing else, the general premise of octopus intelligence had to be admitted as they were able to recognize humans from each other, even humans wearing identical uniforms, and would modify their behavior toward such humans.
Perhaps most impressively, they would attempt to modify the environment to become more hospitable to themselves.
Linquist’s octopuses would mess around with their tank, manipulating and testing it. Linquist had a problem with octopuses deliberately plugging the outflow valves on the tanks by poking in their arms, perhaps to increase the water level. Of course, this flooded the entire lab.
But perhaps what stood out to me the most was that octopi appear to have something akin to a theory of mind and this is all the more surprising given the usually solitary lives led by them. This appears to have been demonstrated when an scientist, Jean Boal, was feeding octopuses frozen shrimp or squid. In the wild, octopuses prefer crab and when provided with processed food, take some time to accept second-rate food.
In this case, however, one octopus appeared to launch a protest to her. After being given the squid by her as the first one to be fed, it did not eat its provided food but held until it and waited for Boan to return to its tank and take notice of it:
It had not eaten its squid, but instead was holding it conspicuously. As Boal stood there, the octopus made its way slowly across the tank toward the outflow pipe, watching her all the way. When it reached the outflow pipe, still watching her, it dumped the squid down the drain.
Overall, octopuses appear to be remarkably curious, with minds flexible much like their bodies – much like how Charlie appeared to be fascinated with carrying a light into the water, they appear to manipulate items in the wild for their purposes in a manner that could almost be called creative: in one example in Indonesia, halved coconuts processed by humans and dumped into the oceans were used by octopuses as portable shelters. The octopus would basically carry both halves skidding across the sandy bottom and then assemble a full sphere of coconut would seeking rest, with itself inside the now reassembled halves.
There are other examples of invertebrate intelligence in this world – some truly dramatic ones, such as ants and bees. Ants have always fascinated me by their adoption of capabilities that could be called “technology”, how they are able to farm fungus and ranch aphids; perhaps even more exotically, their ability to create antibiotic medicine for their fellow nestmates. Bees, of course, have the waggle dance, through which they can communicate to others of the location of flowers and which we have been able to interpret.
But notably, these complex behaviors are all the result of social behavior and the complex needs of eusocial creatures to communicate extensively and exhaustively. Octopuses, on the other hand, are primarily loners. They use their intelligence alone, creatively and intricately, but all by themselves except for the short periods of mating.
And mating, as it might be, is fatal to octopuses. The male, after mating, will shortly die in a few months at most. The female will retreat into a safe location and nurture and groom her eggs, without eating, until her egg sac hatches and whereupon she will die from starvation – sometimes accelerated by self-mutilation, such as ripping off her own tentacles.
This kind of behavior is known as semelparity, which is an animal that expects only to reproduce once in its life(Most mammals do not seem to practice this, but there is one that seems to be notable – the marsupial mice, the males who seem to have so much sex in a short period of time until it invariably kills him.). Why the mother octopus doesn’t seek food at all is interesting, and its perhaps worth speculating that appetite-suppressing hormones are activated after mating in order to prevent the octopus from eating her own offspring – other possibilities include that eating might cause debris or contamination which can draw predators or contaminate her offspring.
A life alone and death after pregnancy seems like an awfully non-social life. But perhaps there is another way to think of sociable behavior and one that returns to our original conception of Cambrian creatures and the development of intelligence as a weapon in the fatal exchanges of predation and escape. Octopuses are both predators and prey, and as such it involves considering the potential path of prey, the perspectives of predators and what everyone else can potentially do.
In that sense, octopuses are intensely social, and have to constantly communicate with animals around them, even if they don’t communicate very much with other octopuses.
And with that, we lead into the final part, where we explore the inner lives and feelings, as it might be, of aquatic creatures that go bubble, debate philosophy and accompany our intelligent flexible friends as they head off into death.
But before that, perhaps there might be evidence that somewhere in the world, octopuses are learning to socialize.
