Just How ‘All That’ Are We?
Jordana Cepelewicz’s profile for Quanta Magazine of new discoveries about a tiny, multicellular animal is just the sort of life sciences writing that I’m into, detailing findings that demonstrate in “lower” animal capacities that we tend to reserve in our thinking and our assumptions for “higher” animals.
In this case, the discovery that through purely biomechanical processes, a placozoan named Trichoplax adhaerens “moves and responds to its environment with agility and seeming purpose, yet it has no neurons or muscles to coordinate its movements”.
For some time now I’ve been fascinated with science that I clumsily (and inaccurately) categorize as We Ain’t All That science. Basically, the idea that just because we evolved complex nervous systems topped by mind-bogglingly complicated brains, it doesn’t necessarily mean that the sorts of things we do are entirely unique. We might do them in some unique ways, but we aren’t necessarily the only ways nature figured out how to do the same, similar, or same-seeming things.
In a trio of preprints totaling more than 100 pages—posted simultaneously on the arxiv.org server last year—he and Bull showed that the behavior of Trichoplaxcould be described entirely in the language of physics and dynamical systems. Mechanical interactions that began at the level of a single cilium, and then multiplied over millions of cells and extended to higher levels of structure, fully explained the coordinated locomotion of the entire animal. The organism doesn’t “choose” what to do. Instead, the horde of individual cilia simply moves—and the animal as a whole performs as though it is being directed by a nervous system. The researchers even showed that the cilia’s dynamics exhibit properties that are commonly seen as distinctive hallmarks of neurons.
Cepelewicz makes reference to slime molds, which lately have been something of the go-to example for I guess what you could call “embodied cognition”. (Sidenote: I once compared the way slime molds offload problem solving to their environment through chemical trails and the like to the way I offload memory tasks like reminders and appointments to my cell phone.) I see in my Pocket archive a couple of good articles on slime molds, including Lacy M. Johnson writing for Orion Magazine.
Throughout their lives, myxomycetes only ever exist as a single cell, inside which the cytoplasm always flows—out to its extremities, back to the center. When it encounters something it likes, such as oatmeal, the cytoplasm pulsates more quickly. If it finds something it dislikes, like salt, quinine, bright light, cold, or caffeine, it pulsates more slowly and moves its cytoplasm away (though it can choose to overcome these preferences if it means survival). In one remarkable study published in Science, Japanese researchers created a model of the Tokyo metropolitan area using oat flakes to represent population centers, and found that Physarum polycephalumconfigured itself into a near replica of the famously intuitive Tokyo rail system. In another experiment, scientists blasted a specimen with cold air at regular intervals, and found that it learned to expect the blast, and would retract in anticipation. It can solve mazes in pursuit of a single oat flake, and later, can recall the path it took to reach it. More remarkable still, a slime mold can grow indefinitely in its plasmodial stage. As long as it has an adequate food supply and is comfortable in its environment, it doesn’t age and it doesn’t die.
Ian McCluskey writing for OPB News descibed a bit of what paces researchers have put slime molds through.
The Japanese researchers tried another experiment. They knew that slime molds avoid unfavorable environmental conditions, such as intense light or salt. They created an unfavorable condition in their lab with pulses from an oscillator as a slime mold moved toward food. As expected, the slime mold reacted by slowing its advance. Then the researchers had the slime mold do it again, but this time didn’t create the pulses. Yet, the slime mold slowed down in the same place the unfavorable condition had been, as if anticipating.
Dussutour wondered if slime molds could learn to tolerate, even adapt, to uncomfortable conditions. She forced slime molds to cross over various substances they disliked in order to reach food. The first time, it took the slime mold 10 hours to reach the food. After a few days, the slime molds began to pick up their pace. After a few more days, they cruised over them at regular slime mold speed. They had apparently “tuned out” the distraction placed in their path, or what scientists call “habituation,” which is a form of learning.
Slime molds are crazy but as the Quanta piece shows, they certainly only the only crazy thing out there that seems to exhibit a kind of, as I say, embodied cognition. “The behavior of slime molds seemed inexplicable,” writes McCluskey. “Was it merely a biological stimulus-response mechanism, or some form of intelligence?”
I think this sort of thing grabs me in part because it makes me wonder just to what degree our own behavior is not all we crack it up to be, and makes me think of things like Dan Folk writing for Aeon about consciousness.
Another problem centres on what consciousness actually does. As a philosopher would put it, what causal role does it play? Does it cause matter to move about? Or to put it another way: does consciousness impact behaviour? By Chalmers’s account, the zombie is supposed to behave exactly like us – even though we have conscious experiences and the zombie doesn’t. The implication seems to be that conscious experiences play no causal role in the world. But in that case, why even postulate its existence? The usual response is that consciousness is something we immediately experience; we can’t be wrong when we claim to be conscious. But when we reach for a glass of water, aren’t we doing so because of the conscious experience of being thirsty? If we are, then consciousness does, in fact, seem to impact behaviour; and if we aren’t, then consciousness seems to be nothing more than what philosophers call an epiphenomenon, a kind of secondary phenomenon. As Hanrahan puts it, consciousness would be like the humming sound that your computer makes – it’s always there when the computer is on, but it has no bearing on what the machine is actually computing.
I’ll admit that with no particular sense of the evidence base in any direction, I’m of the personality type (for lack of a better phrase) to be inclined toward this idea of consciousness as epiphenomenon. I feel like there’s a degree to which our sense of ourselves as animals might be overinflated by our compulsion to tell stories about everything. I do, in fact, think that we probably didn’t “decide”, per se, to reach for the glass of water or to go to brunch the other day instead of having a bowl of cereal at home.
Which is where it’s worth bringing in Mark Balaguer writing for The MIT Press Readerabout free will, adapted from his recent book on the subject.
Suppose that you’re in an ice cream parlor, waiting in line, trying to decide whether to order chocolate or vanilla ice cream. And suppose that when you get to the front of the line, you decide to order chocolate. Was this choice a product of your free will? Well, if determinism is true, then your choice was completely caused by prior events. The immediatecauses of the decision were neural events that occurred in your brain just prior to your choice. […]
I’m not so sure I am a determinist, per se, but when I read things like this I really do just sort of feel the pull of a gut instinct that says neural events happen and then we tell ourselves a story about them after the fact. It’s not so much for me a matter of “free will” versus “determinism” as it’s a matter of our self, whatever that is, being far more (than we’d like to believe) a narrator than an author.
I think that once we evolved the ability to tell stories—it’s a surefire advantage when we can turn to the early hominid next to us and tell them we’ve figured out that every time the mammoth herd visits the local watering hole, that small one strays behind for a bit afterward and we can probably take him—we can’t help but tell stories about very nearly everything, and of course that includes telling stories about what we ourselves do, whether or not they are true.
We tell ourselves and each other a lot of stories, and stories to a large degree are us seeing—or making—patterns out of things. QAnon and Richard Hoagland might tell stories about societal or governmental behavior that sure seem to be picking up on patterns to reveal a hidden truth, but in fact they are complete bullshit. Why not so with what we tell ourselves about ourselves?
I think that in a very many ways, we are full of both ourselves and shit. Nature seems to have found an awful lot of ways to do complex and complicated things with “lesser” brains and nervous systems and even with no brains or nervous systems at all. When we write rapturously about octopus intelligence or whale communication, I think we feel as if we somehow are “elevating” them, whereas I feel like maybe the lesson is that we are not as much of a “higher life form” as we tell ourselves.
As I say, I guess I’m just the personality type to believe that much of what we find so great about ourselves might be a post-hoc fabrication. This is not even dime-store philosophy here: it’s just (yes) the story to which I’m the most drawn, maybe because I’m fond of us being put in our place, which we so often aren’t.
Tiny animals “decide” where to go, fungi “solve” mazes, and forests “talk” to themselves. I’m not always entirely quite so sure why those behaviors deserve a quotation quarantine while our own do not, except that it’s the story we prefer to tell.