Field Notes—

The Optical Delusion Of Turtle Watching

By Curtiss Clark

In thinking about the universe and mankind’s place in it, Albert Einstein spoke about the “optical delusion” of our consciousness. “This delusion,” he said, “is a kind of prison for us restricting us to our personal desires and the affection for a few persons nearest us. Our task must be to free ourselves from this prison by widening our circles of compassion to embrace all living creatures and the whole of nature in its beauty.”

Few of us grasp “the whole of nature” the way Einstein did. His mind ranged freely, well beyond the time and space that confines the rest of us, to describe the esoteric escapements, verges, and balance wheels in the clockwork of the cosmos. With great turtle-like galaxies, 10 billion years old, crawling outward beyond the rim of our dull and distant imaginings, our ordinary consciousness seems stuck in the mud like… well, like real turtles.

I’ve been watching the painted turtles at a nearby pond when they drag themselves up on a sunny rock these late-summer mornings. The turtles are poikilotherms, which like other cold-blooded creatures, vary their body temperature to match their environment.

As mammals, we are homeotherms, maintaining a constant internal temperature. Our dogged devotion to 98.6 degrees and metabolic constancy comes with a price; we expend a great deal of energy maintaining our core temperature when our environment gets too cold or too hot.

So the turtle’s experience of climbing onto a sunny rock on a late-August morning is considerably different from what ours would be, even if we were game enough to immerse ourselves to the cool depths of a funky pond and emerge through the scum to claw our way onto a rock. Lying in the sun, our skin would warm, our heart wouldn’t have to work as hard to pump blood to our extremities, and we wouldn’t have to burn quite so many calories to keep our core temperature steady. The turtle on the rock, on the other hand, has a completely different body temperature and metabolism than it had at the bottom of the pond. I can’t imagine what kind of sensation that transformation must add to sunbathing.

While we’re considering the sentience of turtles in their peculiar environments, let’s consider this: over at the opposite end of the calendar, in late February, these painted turtles I’ve been watching will be buried two or three feet down in the mud of the pond, beneath a few feet of super-chilled water, beneath another foot of ice, beneath the cold discomforting countenance of a New England winter in its full maturity.

Midway through the turtle’s epic winter hunker-down in its bed of mud, the lack of oxygen, or anoxia, has suppressed its metabolic rate to roughly 10 percent of what it would be if it were still breathing at the same temperature. Being 90 percent dead lowers a turtle’s energy demands to the point where its life is fueled solely by the reserves of the carbohydrate glycogen stored in its tissues.

According to Einstein, the “optical delusion” of my own human consciousness is what separates me from the many metabolic lives of turtles — and every other thing that crawls deep into the mud or far out to the rim of the universe. So repose on a sunny rock is assessed by me solely in terms of human repose. Winter survival is human survival. Even dull imaginings on the nature of consciousness are human imaginings.

There is irony in this. In taking a moment to consider the conscious experience of these painted turtles, who carry all of their remarkable existence in a hardened shell across the seasons, a few feet up and a few feet down, I run quickly into my own narrow limits. Fortunately, the “whole of nature” accommodates me just as I am.

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