On fish (and their similarities to us).

On fish (and their similarities to us).

I had a pet leopard gecko when I was growing up – he lived with me from fourth grade until I graduated from high school.  After that, my father took care of him, but I’d visit several times a year.  He would sit on my chest, occasionally skittering up to hide between my chin & neck, or buried in my underarm, while I lay on my back reading a book.

MRLizard.JPG
In all his glory (circa 2002).

He was a good friend to me, Mr. Lizard was (it took me almost an entire year to name him, and this was the name all that cogitation produced).  We had similar interests, mostly involving lying down in warm places to think.  I assume he was thinking.  But I have no idea what he was thinking about.  He rarely spoke – only twice that I remember – and, when he did, he made an irate chirping sound.  We didn’t have a great way to communicate.

But we, as humans, are moving closer to being able to understand some of the thoughts of other animals.  With some species, this is manageable for laypeople.  Dogs, for instance, co-evolved with humans (during which time both their & our brains shrunk as we sloughed certain tasks off onto the others).  Most humans are pretty good at guessing what a dog is thinking, especially when the dog’s thoughts involve wanting the human to scoop kibble or go on a walk.

fishFish, though?  I find fish inscrutable.  Mr. Lizard ate crickets, and the cricket bin at the local pet store was kept in the middle of the fish room, so I spent a lot of time peering into the various aquaria while their inhabitants blurbled lackadaisically about.  I always liked seeing the velvety black goldfish with eyes telescoped outward like hammerhead sharks.  I even bought a few to put into the pond in our backyard, but they swim slowly.  Within a week the raccoons had caught them all.

fishknowsJonathan Balcombe thinks I’ve been unfair, ignoring the thoughts of fish.  In What a Fish Knows, he combs through many decades of research into fish cognition in order to give blithely naive readers like myself some insight into their world.

It would be remiss of me to proceed with this essay without mentioning that, for many years, numerous scientists have argued that fish lack consciousness.  The crux of this argument is that fish brains are very different from human brains.  Indeed, fish lack the brain region that most humans use to process the experience of pain.  But that’s okay – recent animal cognition research has found that very different brain regions can be used for the same tasks in different species, as with parrots learning to sing and human children learning to speak.  And we’ve recently learned that blind humans, who use the brain regions most of us devote to sight for other purposes, are able to rewire their minds if suddenly granted vision.  Thank you Project Prakash.

So I’m not convinced by most of the arguments against fish feeling pain.  Throughout history, we’ve argued over and over again that perceived others don’t feel the way we do.  Descartes claimed that animals were nothing but automata.  White people in the United States often think that black people feel less pain.  That last sentence – I’m not just writing about the horrific way African Americans were treated long ago.  This is about how black people in the U.S. are treated today by highly-educated medical doctors.  Belief in bizarre racial stereotypes is widespread, and one consequence is that doctors offer less treatment for black people in pain than they would for equivalent white patients.

So I’m suspicious of any claims that the way we think, or feel, or suffer, is special.  As is Jonathan Balcombe.  In his words:

Thanks to breakthroughs in ethology, sociobiology, neurobiology, and ecology, we can now better understand what the world looks like to a fish, how they perceive, feel, and experience the world.

What this book explores is a simple possibility with a profound implication.  The simple possibility is that fishes are individual beings whose lives have intrinsic value — that is, value to themselves quite apart from any utilitarian value they might have to us, for example as a source of profit, or of entertainment.  The profound implication is that this would qualify them for inclusion in our circle of moral concern.

Not only is scientific consensus squarely behind consciousness and pain in fishes, consciousness probably evolved first in fishes.  Why?  Because fishes were the first vertebrates, because they had been evolving for well over 100 million years before the ancestors of today’s mammals and birds set foot on land, and because those ancestors would have greatly benefited from having some modicum of wherewithal by the time they started colonizing such dramatically new terrain.

Despite claiming that fish are extremely different from us, scientists have used fish to study human mental conditions for many years.  Since the 1950s, researchers have tried dosing fish with LSD, finding that, like humans, most fish seem to enjoy low doses of psychedelic drugs but are terrified by high doses.  Even today, antisocial cave fish are being investigated as a model to test drugs for autism and schizophrenia.  It is illogical to simultaneously claim that fish may be useful models to understand our own brains and that their brains are so different from ours that they cannot feel pain.

Of course, there probably are very significant differences between our minds and those of fish.  I’ve discussed some of these ideas in two prior speculative essays on octopus literature.  I stumbled across another lovely insight into fish brains in Sean Carroll’s The Big Picture.  He suggests, quite reasonably, that fish brains probably operate faster than our own, with less tendency toward meditative rumination.  His argument is based on the behavior of light in water versus air; in his words:

bigpictureAs far as stimulating new avenues of thought is concerned, the most important feature of their new environment was simply the ability to see a lot farther.  If you’ve spent much time swimming or diving, you know that you can’t see as far underwater as you can in air.  The attenuation length – the distance past which light is mostly absorbed by the medium you are looking through – is tens of meters through clear water, while in air it’s practically infinite. (We have no trouble seeing the moon, or distant objects on our horizon.)

What you see has a dramatic effect on how you think.  If you’re a fish, you move through the water at a meter or two per second, and you see some tens of meters in front of you.  Every few seconds you are entering a new perceptual environment.  As something new looms into your view, you have only a very brief amount of time in which to evaluate how to react to it.  Is it friendly, fearsome, or foodlike?

Under these conditions, there is enormous evolutionary pressure to think fast.  See something, respond almost immediately.  A fish brain is going to be optimized to do just that.  Quick reaction, not leisurely contemplation, is the name of the game.

Now imagine you’ve climbed up onto land.  Suddenly your sensory horizon expands enormously.  Surrounded by clear air, you can see for kilometers – much farther than you can travel in a couple of seconds.  At first, there wasn’t much to see, since there weren’t any other animals up there with you.  But there is food of different varieties, obstacles like rocks and trees, not to mention the occasional geological eruption.  And before you know it, you are joined by other kinds of locomotive creatures.  Some friendly, some tasty, some simply to be avoided.

Now the selection pressures have shifted dramatically.  Being simple-minded and reactive might be okay in some circumstances, but it’s not the best strategy on land.  When you can see what’s coming long before you are forced to react, you have the time to contemplate different possible actions, and weigh the pros and cons of each.  You can even be ingenious, putting some of your cognitive resources into inventing plans of action other than those that are immediately obvious.

Out in the clear air, it pays to use your imagination.

(An aside, added later, not about fish: dolphin sonar & whale songs often travel farther in water than visible light does near the Earth’s surface, perhaps inclining whales & dolphins to be more imaginative and introspective than land animals.  I neglected this thought when I first posted the essay because it’s hard to avoid favoring our own forms of perception.)

Human brains are amazing.  I think that goes without saying, especially because my ability to type the words “I think that goes without saying” is already a dramatic demonstration of our mental capacity.  As is your ability to read those words and understand roughly what I meant.

And yet.  Our brains are sufficiently remarkable that I think there’s no need to denigrate the cognitive abilities of other animals.  They can feel.  They can think.  They almost certainly have their own wants and desires.

Recognizing their value shouldn’t make us feel bad about our own minds, though.

We’ve come a long way.  We still have more, as a species, to do.  That’s glaringly obvious to anyone who so much as glances at the news.  Still, I’d like to think that the average person is doing a better job of recognizing the concerns of others than was common in our past.  There is dramatically less (but non-zero) slavery in the modern world than in the past.  And we treat non-human animals far more kindly than we used to.

From Frans de Waal’s Are We Smart Enough to Know How Smart Animals Are?:

smartenoughDesmond Morris once told me an amusing story to drive this point home.  At the time Desmond was working at the London Zoo, which still held tea parties in the ape house with the public looking on.  Gathered on chairs around a table, the apes had been trained to use bowls, spoons, cups, and a teapot.  Naturally, this equipment posed no problem for these tool-using animals.  Unfortunately, over time the apes became too polished and their performance too perfect for the English public, for whom high tea constitutes the peak of civilization.  When the public tea parties began to threaten the human ego, something had to be done.  The apes were retrained to spill the tea, throw food around, drink from the teapot’s spout, and pop the cups into the bowl as soon as the keeper turned his back.  The public loved it!  The apes were wild and naughty, as they were supposed to be.