By JIM HOLT | The New York Review of Books May 23, 2013
Benoit Mandelbrot, the brilliant Polish-French-American mathematician who died in 2010, had a poet’s taste for complexity and strangeness. His genius for noticing deep links among far-flung phenomena led him to create a new branch of geometry, one that has deepened our understanding of both natural forms and patterns of human behavior. The key to it is a simple yet elusive idea, that of self-similarity.
To see what self-similarity means, consider a homely example: the cauliflower. Take a head of this vegetable and observe its form—the way it is composed of florets. Pull off one of those florets. What does it look like? It looks like a little head of cauliflower, with its own subflorets. Now pull off one of those subflorets. What does that look like? A still tinier cauliflower. If you continue this process—and you may soon need a magnifying glass—you’ll find that the smaller and smaller pieces all resemble the head you started with. The cauliflower is thus said to be self-similar. Each of its parts echoes the whole.
Other self-similar phenomena, each with its distinctive form, include clouds, coastlines, bolts of lightning, clusters of galaxies, the network of blood vessels in our bodies, and, quite possibly, the pattern of ups and downs in financial markets. The closer you look at a coastline, the more you find it is jagged, not smooth, and each jagged segment contains smaller, similarly jagged segments that can be described by Mandelbrot’s methods. Because of the essential roughness of self-similar forms, classical mathematics is ill-equipped to deal with them. Its methods, from the Greeks on down to the last century, have been better suited to smooth forms, like circles. (Note that a circle is not self-similar: if you cut it up into smaller and smaller segments, those segments become nearly straight.)
Only in the last few decades has a mathematics of roughness emerged, one that can get a grip on self-similarity and kindred matters like turbulence, noise, clustering, and chaos. And Mandelbrot was the prime mover behind it.
Pictured above, the Sakurajima volcano in southern Japan was caught erupting in early January. Magma bubbles so hot they glow shoot away as liquid rock bursts through the Earth’s surface from below. The above image is particularly notable, however, for the lightning bolts caught near the volcano’s summit. Why lightning occurs even in common thunderstorms remains a topic of research, and the cause of volcanic lightning is even less clear. Surely, lightning bolts help quench areas of opposite but separated electric charges. One hypothesis holds that catapulting magma bubbles or volcanic ash are themselves electrically charged, and by their motion create these separated areas. Other volcanic lightning episodes may be facilitated by charge-inducing collisions in volcanic dust. Lightning is usually occurring somewhere on Earth, typically over 40 times each second.
[…] For all scientists and statisticians now know of freezing and its physiology, no one can yet predict exactly how quickly and in whom hypothermia will strike—and whether it will kill when it does. The cold remains a mystery, more prone to fell men than women, more lethal to the thin and well muscled than to those with avoirdupois, and least forgiving to the arrogant and the unaware.
The process begins even before you leave the car, when you remove your gloves to squeeze a loose bail back into one of your ski bindings. The freezing metal bites your flesh. Your skin temperature drops.
Within a few seconds, the palms of your hands are a chilly, painful 60 degrees. Instinctively, the web of surface capillaries on your hands constrict, sending blood coursing away from your skin and deeper into your torso. Your body is allowing your fingers to chill in order to keep its vital organs warm.
You replace your gloves, noticing only that your fingers have numbed slightly. Then you kick boots into bindings and start up the road.
Were you a Norwegian fisherman or Inuit hunter, both of whom frequently work gloveless in the cold, your chilled hands would open their surface capillaries periodically to allow surges of warm blood to pass into them and maintain their flexibility. This phenomenon, known as the hunter’s response, can elevate a 35-degree skin temperature to 50 degrees within seven or eight minutes.
Other human adaptations to the cold are more mysterious. Tibetan Buddhist monks can raise the skin temperature of their hands and feet by 15 degrees through meditation. Australian aborigines, who once slept on the ground, unclothed, on near-freezing nights, would slip into a light hypothermic state, suppressing shivering until the rising sun rewarmed them.
You have no such defenses, having spent your days at a keyboard in a climate-controlled office. Only after about ten minutes of hard climbing, as your body temperature rises, does blood start seeping back into your fingers. Sweat trickles down your sternum and spine.
By now you’ve left the road and decided to shortcut up the forested mountainside to the road’s next switchback. Treading slowly through deep, soft snow as the full moon hefts over a spiny ridgetop, throwing silvery bands of moonlight and shadow, you think your friends were right: It’s a beautiful night for skiing—though you admit, feeling the minus-30 air bite at your face, it’s also cold.
After an hour, there’s still no sign of the switchback, and you’ve begun to worry. You pause to check the map. At this moment, your core temperature reaches its high: 100.8. Climbing in deep snow, you’ve generated nearly ten times as much body heat as you do when you are resting.
As you step around to orient map to forest, you hear a metallic pop. You look down. The loose bail has disappeared from your binding. You lift your foot and your ski falls from your boot.
You twist on your flashlight, and its cold-weakened batteries throw a yellowish circle in the snow. It’s right around here somewhere, you think, as you sift the snow through gloved fingers. Focused so intently on finding the bail, you hardly notice the frigid air pressing against your tired body and sweat-soaked clothes.
The exertion that warmed you on the way uphill now works against you: Your exercise-dilated capillaries carry the excess heat of your core to your skin, and your wet clothing dispels it rapidly into the night. The lack of insulating fat over your muscles allows the cold to creep that much closer to your warm blood.
Your temperature begins to plummet. Within 17 minutes it reaches the normal 98.6. Then it slips below.
At 97 degrees, hunched over in your slow search, the muscles along your neck and shoulders tighten in what’s known as pre-shivering muscle tone. Sensors have signaled the temperature control center in your hypothalamus, which in turn has ordered the constriction of the entire web of surface capillaries. Your hands and feet begin to ache with cold. Ignoring the pain, you dig carefully through the snow; another ten minutes pass. Without the bail you know you’re in deep trouble.
Finally, nearly 45 minutes later, you find the bail. You even manage to pop it back into its socket and clamp your boot into the binding. But the clammy chill that started around your skin has now wrapped deep into your body’s core.
At 95, you’ve entered the zone of mild hypothermia. You’re now trembling violently as your body attains its maximum shivering response, an involuntary condition in which your muscles contract rapidly to generate additional body heat.
It was a mistake, you realize, to come out on a night this cold. You should turn back. Fishing into the front pocket of your shell parka, you fumble out the map. You consulted it to get here; it should be able to guide you back to the warm car. It doesn’t occur to you in your increasingly clouded and panicky mental state that you could simply follow your tracks down the way you came.
And after this long stop, the skiing itself has become more difficult. By the time you push off downhill, your muscles have cooled and tightened so dramatically that they no longer contract easily, and once contracted, they won’t relax. You’re locked into an ungainly, spread-armed, weak-kneed snowplow.
Still, you manage to maneuver between stands of fir, swishing down through silvery light and pools of shadow. You’re too cold to think of the beautiful night or of the friends you had meant to see. You think only of the warm Jeep that waits for you somewhere at the bottom of the hill. Its gleaming shell is centered in your mind’s eye as you come over the crest of a small knoll. You hear the sudden whistle of wind in your ears as you gain speed. Then, before your mind can quite process what the sight means, you notice a lump in the snow ahead.
Recognizing, slowly, the danger that you are in, you try to jam your skis to a stop. But in your panic, your balance and judgment are poor. Moments later, your ski tips plow into the buried log and you sail headfirst through the air and bellyflop into the snow.
You lie still. There’s a dead silence in the forest, broken by the pumping of blood in your ears. Your ankle is throbbing with pain and you’ve hit your head. You’ve also lost your hat and a glove. Scratchy snow is packed down your shirt. Meltwater trickles down your neck and spine, joined soon by a thin line of blood from a small cut on your head.
This situation, you realize with an immediate sense of panic, is serious. Scrambling to rise, you collapse in pain, your ankle crumpling beneath you.
As you sink back into the snow, shaken, your heat begins to drain away at an alarming rate, your head alone accounting for 50 percent of the loss. The pain of the cold soon pierces your ears so sharply that you root about in the snow until you find your hat and mash it back onto your head.
But even that little activity has been exhausting. You know you should find your glove as well, and yet you’re becoming too weary to feel any urgency. You decide to have a short rest before going on.
An hour passes. at one point, a stray thought says you should start being scared, but fear is a concept that floats somewhere beyond your immediate reach, like that numb hand lying naked in the snow. You’ve slid into the temperature range at which cold renders the enzymes in your brain less efficient. With every one-degree drop in body temperature below 95, your cerebral metabolic rate falls off by 3 to 5 percent. When your core temperature reaches 93, amnesia nibbles at your consciousness. You check your watch: 12:58. Maybe someone will come looking for you soon. Moments later, you check again. You can’t keep the numbers in your head. You’ll remember little of what happens next.
Your head drops back. The snow crunches softly in your ear. In the minus-35-degree air, your core temperature falls about one degree every 30 to 40 minutes, your body heat leaching out into the soft, enveloping snow. Apathy at 91 degrees. Stupor at 90.
You’ve now crossed the boundary into profound hypothermia. By the time your core temperature has fallen to 88 degrees, your body has abandoned the urge to warm itself by shivering. Your blood is thickening like crankcase oil in a cold engine. Your oxygen consumption, a measure of your metabolic rate, has fallen by more than a quarter. Your kidneys, however, work overtime to process the fluid overload that occurred when the blood vessels in your extremities constricted and squeezed fluids toward your center. You feel a powerful urge to urinate, the only thing you feel at all.
By 87 degrees you’ve lost the ability to recognize a familiar face, should one suddenly appear from the woods.
At 86 degrees, your heart, its electrical impulses hampered by chilled nerve tissues, becomes arrhythmic. It now pumps less than two-thirds the normal amount of blood. The lack of oxygen and the slowing metabolism of your brain, meanwhile, begin to trigger visual and auditory hallucinations.
You hear jingle bells. Lifting your face from your snow pillow, you realize with a surge of gladness that they’re not sleigh bells; they’re welcoming bells hanging from the door of your friends’ cabin. You knew it had to be close by. The jingling is the sound of the cabin door opening, just through the fir trees.
Attempting to stand, you collapse in a tangle of skis and poles. That’s OK. You can crawl. It’s so close.
Hours later, or maybe it’s minutes, you realize the cabin still sits beyond the grove of trees. You’ve crawled only a few feet. The light on your wristwatch pulses in the darkness: 5:20. Exhausted, you decide to rest your head for a moment.
When you lift it again, you’re inside, lying on the floor before the woodstove. The fire throws off a red glow. First it’s warm; then it’s hot; then it’s searing your flesh. Your clothing has caught fire.
At 85 degrees, those freezing to death, in a strange, anguished paroxysm, often rip off their clothes. This phenomenon, known as paradoxical undressing, is common enough that urban hypothermia victims are sometimes initially diagnosed as victims of sexual assault. Though researchers are uncertain of the cause, the most logical explanation is that shortly before loss of consciousness, the constricted blood vessels near the body’s surface suddenly dilate and produce a sensation of extreme heat against the skin.
All you know is that you’re burning. You claw off your shell and pile sweater and fling them away.
But then, in a final moment of clarity, you realize there’s no stove, no cabin, no friends. You’re lying alone in the bitter cold, naked from the waist up. You grasp your terrible misunderstanding, a whole series of misunderstandings, like a dream ratcheting into wrongness. You’ve shed your clothes, your car, your oil-heated house in town. Without this ingenious technology you’re simply a delicate, tropical organism whose range is restricted to a narrow sunlit band that girds the earth at the equator.
And you’ve now ventured way beyond it.
There’s an adage about hypothermia: “You aren’t dead until you’re warm and dead.”
At about 6:00 the next morning, his friends, having discovered the stalled Jeep, find him, still huddled inches from the buried log, his gloveless hand shoved into his armpit. The flesh of his limbs is waxy and stiff as old putty, his pulse nonexistent, his pupils unresponsive to light. Dead.
But those who understand cold know that even as it deadens, it offers perverse salvation. Heat is a presence: the rapid vibrating of molecules. Cold is an absence: the damping of the vibrations. At absolute zero, minus 459.67 degrees Fahrenheit, molecular motion ceases altogether. It is this slowing that converts gases to liquids, liquids to solids, and renders solids harder. It slows bacterial growth and chemical reactions. In the human body, cold shuts down metabolism. The lungs take in less oxygen, the heart pumps less blood. Under normal temperatures, this would produce brain damage. But the chilled brain, having slowed its own metabolism, needs far less oxygen-rich blood and can, under the right circumstances, survive intact.
Setting her ear to his chest, one of his rescuers listens intently. Seconds pass. Then, faintly, she hears a tiny sound—a single thump, so slight that it might be the sound of her own blood. She presses her ear harder to the cold flesh. Another faint thump, then another.
After more than 4,000 years — almost since the dawn of recorded time, when Utnapishtim told Gilgamesh that the secret to immortality lay in a coral found on the ocean floor — man finally discovered eternal life in 1988. He found it, in fact, on the ocean floor. The discovery was made unwittingly by Christian Sommer, a German marine-biology student in his early 20s. He was spending the summer in Rapallo, a small city on the Italian Riviera, where exactly one century earlier Friedrich Nietzsche conceived “Thus Spoke Zarathustra”: “Everything goes, everything comes back; eternally rolls the wheel of being. Everything dies, everything blossoms again…”
Sommer was conducting research on hydrozoans, small invertebrates that, depending on their stage in the life cycle, resemble either a jellyfish or a soft coral. Every morning, Sommer went snorkeling in the turquoise water off the cliffs of Portofino. He scanned the ocean floor for hydrozoans, gathering them with plankton nets. Among the hundreds of organisms he collected was a tiny, relatively obscure species known to biologists as Turritopsis dohrnii. Today it is more commonly known as the immortal jellyfish.
Sommer kept his hydrozoans in petri dishes and observed their reproduction habits. After several days he noticed that his Turritopsis dohrnii was behaving in a very peculiar manner, for which he could hypothesize no earthly explanation. Plainly speaking, it refused to die. It appeared to age in reverse, growing younger and younger until it reached its earliest stage of development, at which point it began its life cycle anew.
Sommer was baffled by this development but didn’t immediately grasp its significance. (It was nearly a decade before the word “immortal” was first used to describe the species.) But several biologists in Genoa, fascinated by Sommer’s finding, continued to study the species, and in 1996 they published a paper called “Reversing the Life Cycle.” The scientists described how the species — at any stage of its development — could transform itself back to a polyp, the organism’s earliest stage of life, “thus escaping death and achieving potential immortality.” This finding appeared to debunk the most fundamental law of the natural world — you are born, and then you die.
One of the paper’s authors, Ferdinando Boero, likened the Turritopsis to a butterfly that, instead of dying, turns back into a caterpillar. Another metaphor is a chicken that transforms into an egg, which gives birth to another chicken. The anthropomorphic analogy is that of an old man who grows younger and younger until he is again a fetus. For this reason Turritopsis dohrnii is often referred to as the Benjamin Button jellyfish. Read on
Taken in various locations around Maniwa (Okayama Prefecture) between 2008 and 2011 this series of photographs captures the wild frenzy of gold fireflies as they mate after thunderstorms during the June to July rainy season. Shot using a slow shutter speed, the neon green and yellow contrails seem almost digitally imposed on the scenic landscapes. (via)
On an unseasonably warm day in the middle of March, I traveled from New Hampshire to the moist, dim sanctuary of the New England Aquarium, hoping to touch an alternate reality. I came to meet Athena, the aquarium’s forty-pound, five-foot-long, two-and-a-half-year-old giant Pacific octopus.
For me, it was a momentous occasion. I have always loved octopuses. No sci-fi alien is so startlingly strange. Here is someone who, even if she grows to one hundred pounds and stretches more than eight feet long, could still squeeze her boneless body through an opening the size of an orange; an animal whose eight arms are covered with thousands of suckers that taste as well as feel; a mollusk with a beak like a parrot and venom like a snake and a tongue covered with teeth; a creature who can shape-shift, change color, and squirt ink. But most intriguing of all, recent research indicates that octopuses are remarkably intelligent.
Many times I have stood mesmerized by an aquarium tank, wondering, as I stared into the horizontal pupils of an octopus’s large, prominent eyes, if she was staring back at me—and if so, what was she thinking?
Not long ago, a question like this would have seemed foolish, if not crazy. How can an octopus know anything, much less form an opinion? Octopuses are, after all, “only” invertebrates—they don’t even belong with the insects, some of whom, like dragonflies and dung beetles, at least seem to show some smarts. Octopuses are classified within the invertebrates in the mollusk family, and many mollusks, like clams, have no brain.
Only recently have scientists accorded chimpanzees, so closely related to humans we can share blood transfusions, the dignity of having a mind. But now, increasingly, researchers who study octopuses are convinced that these boneless, alien animals—creatures whose ancestors diverged from the lineage that would lead to ours roughly 500 to 700 million years ago—have developed intelligence, emotions, and individual personalities. Their findings are challenging our understanding of consciousness itself.
I had always longed to meet an octopus. Now was my chance: senior aquarist Scott Dowd arranged an introduction. In a back room, he would open the top of Athena’s tank. If she consented, I could touch her. The heavy lid covering her tank separated our two worlds. One world was mine and yours, the reality of air and land, where we lumber through life governed by a backbone and constrained by jointed limbs and gravity. The other world was hers, the reality of a nearly gelatinous being breathing water and moving weightlessly through it. We think of our world as the “real” one, but Athena’s is realer still: after all, most of the world is ocean, and most animals live there. Regardless of whether they live on land or water, more than 95 percent of all animals are invertebrates, like Athena.
The moment the lid was off, we reached for each other. She had already oozed from the far corner of her lair, where she had been hiding, to the top of the tank to investigate her visitor. Her eight arms boiled up, twisting, slippery, to meet mine. I plunged both my arms elbow deep into the fifty-seven-degree water. Athena’s melon-sized head bobbed to the surface. Her left eye (octopuses have one dominant eye like humans have a dominant hand) swiveled in its socket to meet mine. “She’s looking at you,” Dowd said.
As we gazed into each other’s eyes, Athena encircled my arms with hers, latching on with first dozens, then hundreds of her sensitive, dexterous suckers. Each arm has more than two hundred of them. The famous naturalist and explorer William Beebe found the touch of the octopus repulsive. “I have always a struggle before I can make my hands do their duty and seize a tentacle,” he confessed. But to me, Athena’s suckers felt like an alien’s kiss—at once a probe and a caress. Although an octopus can taste with all of its skin, in the suckers both taste and touch are exquisitely developed. Athena was tasting me and feeling me at once, knowing my skin, and possibly the blood and bone beneath, in a way I could never fathom.
When I stroked her soft head with my fingertips, she changed color beneath my touch, her ruby-flecked skin going white and smooth. This, I learned, is a sign of a relaxed octopus. An agitated giant Pacific octopus turns red, its skin gets pimply, and it erects two papillae over the eyes, which some divers say look like horns. One name for the species is “devil fish.” With sharp, parrotlike beaks, octopuses can bite, and most have neurotoxic, flesh-dissolving venom. The pressure from an octopus’s suckers can tear flesh (one scientist calculated that to break the hold of the suckers of the much smaller common octopus would require a quarter ton of force). One volunteer who interacted with an octopus left the aquarium with arms covered in red hickeys.
Occasionally an octopus takes a dislike to someone. One of Athena’s predecessors at the aquarium, Truman, felt this way about a female volunteer. Using his funnel, the siphon near the side of the head used to jet through the sea, Truman would shoot a soaking stream of salt water at this young woman whenever he got a chance. Later, she quit her volunteer position for college. But when she returned to visit several months later, Truman, who hadn’t squirted anyone in the meanwhile, took one look at her and instantly soaked her again.
Athena was remarkably gentle with me—even as she began to transfer her grip from her smaller, outer suckers to the larger ones. She seemed to be slowly but steadily pulling me into her tank. Had it been big enough to accommodate my body, I would have gone in willingly. But at this point, I asked Dowd if perhaps I should try to detach from some of the suckers. With his help, Athena and I pulled gently apart.
I was honored that she appeared comfortable with me. But what did she know about me that informed her opinion? When Athena looked into my eyes, what was she thinking?
WHILE ALEXA WARBURTON was researching her senior thesis at Middlebury College’s newly created octopus lab, “every day,” she said, “was a disaster.”
She was working with two species: the California two-spot, with a head the size of a clementine, and the smaller, Florida species, Octopus joubini. Her objective was to study the octopuses’ behavior in a T-shaped maze. But her study subjects were constantly thwarting her.
The first problem was keeping the octopuses alive. The four-hundred-gallon tank was divided into separate compartments for each animal. But even though students hammered in dividers, the octopuses found ways to dig beneath them—and eat each other. Or they’d mate, which is equally lethal. Octopuses die after mating and laying eggs, but first they go senile, acting like a person with dementia. “They swim loop-the-loop in the tank, they look all googly-eyed, they won’t look you in the eye or attack prey,” Warburton said. One senile octopus crawled out of the tank, squeezed into a crack in the wall, dried up, and died.
It seemed to Warburton that some of the octopuses were purposely uncooperative. To run the T-maze, the pre-veterinary student had to scoop an animal from its tank with a net and transfer it to a bucket. With bucket firmly covered, octopus and researcher would take the elevator down to the room with the maze. Some octopuses did not like being removed from their tanks. They would hide. They would squeeze into a corner where they couldn’t be pried out. They would hold on to some object with their arms and not let go.
Some would let themselves be captured, only to use the net as a trampoline. They’d leap off the mesh and onto the floor—and then run for it. Yes, run. “You’d chase them under the tank, back and forth, like you were chasing a cat,” Warburton said. “It’s so weird!”
Octopuses in captivity actually escape their watery enclosures with alarming frequency. While on the move, they have been discovered on carpets, along bookshelves, in a teapot, and inside the aquarium tanks of other fish—upon whom they have usually been dining.
Even though the Middlebury octopuses were disaster prone, Warburton liked certain individuals very much. Some, she said, “would lift their arms out of the water like dogs jump up to greet you.” Though in their research papers the students refer to each octopus by a number, the students named them all. One of the joubini was such a problem they named her The Bitch. “Catching her for the maze always took twenty minutes,” Warburton said. “She’d grip onto something and not let go. Once she got stuck in a filter and we couldn’t get her out. It was awful!”
Then there was Wendy. Warburton used Wendy as part of her thesis presentation, a formal event that was videotaped. First Wendy squirted salt water at her, drenching her nice suit. Then, as Warburton tried to show how octopuses use the T-maze, Wendy scurried to the bottom of the tank and hid in the sand. Warburton says the whole debacle occurred because the octopus realized in advance what was going to happen. “Wendy,” she said, “just didn’t feel like being caught in the net.”
Data from Warburton’s experiments showed that the California two-spots quickly learned which side of a T-maze offered a terra-cotta pot to hide in. But Warburton learned far more than her experiments revealed. “Science,” she says, “can only say so much. I know they watched me. I know they sometimes followed me. But they are so different from anything we normally study. How do you prove the intelligence of someone so different?”
MEASURING THE MINDS OF OTHER creatures is a perplexing problem. One yardstick scientists use is brain size, since humans have big brains. But size doesn’t always match smarts. As is well known in electronics, anything can be miniaturized. Small brain size was the evidence once used to argue that birds were stupid—before some birds were proven intelligent enough to compose music, invent dance steps, ask questions, and do math.
Octopuses have the largest brains of any invertebrate. Athena’s is the size of a walnut—as big as the brain of the famous African gray parrot, Alex, who learned to use more than one hundred spoken words meaningfully. That’s proportionally bigger than the brains of most of the largest dinosaurs.
Another measure of intelligence: you can count neurons. The common octopus has about 130 million of them in its brain. A human has 100 billion. But this is where things get weird. Three-fifths of an octopus’s neurons are not in the brain; they’re in its arms.
“It is as if each arm has a mind of its own,” says Peter Godfrey-Smith, a diver, professor of philosophy at the Graduate Center of the City University of New York, and an admirer of octopuses. For example, researchers who cut off an octopus’s arm (which the octopus can regrow) discovered that not only does the arm crawl away on its own, but if the arm meets a food item, it seizes it—and tries to pass it to where the mouth would be if the arm were still connected to its body.
“Meeting an octopus,” writes Godfrey-Smith, “is like meeting an intelligent alien.” Their intelligence sometimes even involves changing colors and shapes. One video online shows a mimic octopus alternately morphing into a flatfish, several sea snakes, and a lionfish by changing color, altering the texture of its skin, and shifting the position of its body. Another video shows an octopus materializing from a clump of algae. Its skin exactly matches the algae from which it seems to bloom—until it swims away.
For its color palette, the octopus uses three layers of three different types of cells near the skin’s surface. The deepest layer passively reflects background light. The topmost may contain the colors yellow, red, brown, and black. The middle layer shows an array of glittering blues, greens, and golds. But how does an octopus decide what animal to mimic, what colors to turn? Scientists have no idea, especially given that octopuses are likely colorblind.
But new evidence suggests a breathtaking possibility. Woods Hole Marine Biological Laboratory and University of Washington researchers found that the skin of the cuttlefish Sepia officinalis, a color-changing cousin of octopuses, contains gene sequences usually expressed only in the light-sensing retina of the eye. In other words, cephalopods—octopuses, cuttlefish, and squid—may be able to see with their skin.
The American philosopher Thomas Nagel once wrote a famous paper titled “What Is It Like to Be a Bat?” Bats can see with sound. Like dolphins, they can locate their prey using echoes. Nagel concluded it was impossible to know what it’s like to be a bat. And a bat is a fellow mammal like us—not someone who tastes with its suckers, sees with its skin, and whose severed arms can wander about, each with a mind of its own. Nevertheless, there are researchers still working diligently to understand what it’s like to be an octopus.
JENNIFER MATHER SPENT MOST of her time in Bermuda floating facedown on the surface of the water at the edge of the sea. Breathing through a snorkel, she was watching Octopus vulgaris—the common octopus. Although indeed common (they are found in tropical and temperate waters worldwide), at the time of her study in the mid-1980s, “nobody knew what they were doing.”
In a relay with other students from six-thirty in the morning till six-thirty at night, Mather worked to find out. Sometimes she’d see an octopus hunting. A hunting expedition could take five minutes or three hours. The octopus would capture something, inject it with venom, and carry it home to eat. “Home,” Mather found, is where octopuses spend most of their time. A home, or den, which an octopus may occupy only a few days before switching to a new one, is a place where the shell-less octopus can safely hide: a hole in a rock, a discarded shell, or a cubbyhole in a sunken ship. One species, the Pacific red octopus, particularly likes to den in stubby, brown, glass beer bottles.
One octopus Mather was watching had just returned home and was cleaning the front of the den with its arms. Then, suddenly, it left the den, crawled a meter away, picked up one particular rock and placed the rock in front of the den. Two minutes later, the octopus ventured forth to select a second rock. Then it chose a third. Attaching suckers to all the rocks, the octopus carried the load home, slid through the den opening, and carefully arranged the three objects in front. Then it went to sleep. What the octopus was thinking seemed obvious: “Three rocks are enough. Good night!”
The scene has stayed with Mather. The octopus “must have had some concept,” she said, “of what it wanted to make itself feel safe enough to go to sleep.” And the octopus knew how to get what it wanted: by employing foresight, planning—and perhaps even tool use. Mather is the lead author of Octopus: The Ocean’s Intelligent Invertebrate, which includes observations of octopuses who dismantle Lego sets and open screw-top jars. Coauthor Roland Anderson reports that octopuses even learned to open the childproof caps on Extra Strength Tylenol pill bottles—a feat that eludes many humans with university degrees.
In another experiment, Anderson gave octopuses plastic pill bottles painted different shades and with different textures to see which evoked more interest. Usually each octopus would grasp a bottle to see if it were edible and then cast it off. But to his astonishment, Anderson saw one of the octopuses doing something striking: she was blowing carefully modulated jets of water from her funnel to send the bottle to the other end of her aquarium, where the water flow sent it back to her. She repeated the action twenty times. By the eighteenth time, Anderson was already on the phone with Mather with the news: “She’s bouncing the ball!”
This octopus wasn’t the only one to use the bottle as a toy. Another octopus in the study also shot water at the bottle, sending it back and forth across the water’s surface, rather than circling the tank. Anderson’s observations were reported in the Journal of Comparative Psychology. “This fit all the criteria for play behavior,” said Anderson. “Only intelligent animals play—animals like crows and chimps, dogs and humans.”
Aquarists who care for octopuses feel that not only can these animals play with toys, but they may need to play with toys. An Octopus Enrichment Handbook has been developed by Cincinnati’s Newport Aquarium, with ideas of how to keep these creatures entertained. One suggestion is to hide food inside Mr. Potato Head and let your octopus dismantle it. At the Seattle Aquarium, giant Pacific octopuses play with a baseball-sized plastic ball that can be screwed together by twisting the two halves. Sometimes the mollusks screw the halves back together after eating the prey inside.
At the New England Aquarium, it took an engineer who worked on the design of cubic zirconium to devise a puzzle worthy of a brain like Athena’s. Wilson Menashi, who began volunteering at the aquarium weekly after retiring from the Arthur D. Little Corporation sixteen years ago, devised a series of three Plexiglas cubes, each with a different latch. The smallest cube has a sliding latch that twists to lock down, like the bolt on a horse stall. Aquarist Bill Murphy puts a crab inside the clear cube and leaves the lid open. Later he lets the octopus lift open the lid. Finally he locks the lid, and invariably the octopus figures out how to open it.
Next he locks the first cube within a second one. The new latch slides counterclockwise to catch on a bracket. The third box is the largest, with two different locks: a bolt that slides into position to lock down, and a second one like a lever arm, sealing the lid much like the top of an old-fashioned glass canning jar.
All the octopuses Murphy has known learned fast. They typically master a box within two or three once-a-week tries. “Once they ‘get it,’” he says, “they can open it very fast”—within three or four minutes. But each may use a different strategy.
George, a calm octopus, opened the boxes methodically. The impetuous Gwenevere squeezed the second-largest box so hard she broke it, leaving a hole two inches wide. Truman, Murphy said, was “an opportunist.” One day, inside the smaller of the two boxes, Murphy put two crabs, who started to fight. Truman was too excited to bother with locks. He poured his seven-foot-long body through the two-inch crack Gwenevere had made, and visitors looked into his exhibit to find the giant octopus squeezed, suckers flattened, into the tiny space between the walls of the fourteen-cubic-inch box outside and the six-cubic-inch one inside it. Truman stayed inside half an hour. He never opened the inner box—probably he was too cramped.
Three weeks after I had first met Athena, I returned to the aquarium to meet the man who had designed the cubes. Menashi, a quiet grandfather with a dark moustache, volunteers every Tuesday. “He has a real way with octopuses,” Dowd and Murphy told me. I was eager to see how Athena behaved with him.
Murphy opened the lid of her tank, and Athena rose to the surface eagerly. A bucket with a handful of fish sat nearby. Did she rise so eagerly sensing the food? Or was it the sight of her friend that attracted her? “She knows me,” Menashi answered softly.
Anderson’s experiments with giant Pacific octopuses in Seattle prove Menashi is right. The study exposed eight octopuses to two unfamiliar humans, dressed identically in blue aquarium shirts. One person consistently fed a particular octopus, and another always touched it with a bristly stick. Within a week, at first sight of the people, most octopuses moved toward the feeders and away from the irritators, at whom they occasionally aimed their water-shooting funnels.
Upon seeing Menashi, Athena reached up gently and grasped his hands and arms. She flipped upside down, and he placed a capelin in some of the suckers near her mouth, at the center of her arms. The fish vanished. After she had eaten, Athena floated in the tank upside down, like a puppy asking for a belly rub. Her arms twisted lazily. I took one in my hand to feel the suckers—did that arm know it had hold of a different person than the other arms did? Her grip felt calm, relaxed. With me, earlier, she seemed playful, exploratory, excited. The way she held Menashi with her suckers seemed to me like the way a long-married couple holds hands at the movies.
I leaned over the tank to look again into her eyes, and she bobbed up to return my gaze. “She has eyelids like a person does,” Menashi said. He gently slid his hand near one of her eyes, causing her to slowly wink.
BIOLOGISTS HAVE LONG NOTED the similarities between the eyes of an octopus and the eyes of a human. Canadian zoologist N. J. Berrill called it “the single most startling feature of the whole animal kingdom” that these organs are nearly identical: both animals’ eyes have transparent corneas, regulate light with iris diaphragms, and focus lenses with a ring of muscle.
Scientists are currently debating whether we and octopuses evolved eyes separately, or whether a common ancestor had the makings of the eye. But intelligence is another matter. “The same thing that got them their smarts isn’t the same thing that got us our smarts,” says Mather, “because our two ancestors didn’t have any smarts.” Half a billion years ago, the brainiest thing on the planet had only a few neurons. Octopus and human intelligence evolved independently.
“Octopuses,” writes philosopher Godfrey-Smith, “are a separate experiment in the evolution of the mind.” And that, he feels, is what makes the study of the octopus mind so philosophically interesting.
The octopus mind and the human mind probably evolved for different reasons. Humans—like other vertebrates whose intelligence we recognize (parrots, elephants, and whales)—are long-lived, social beings. Most scientists agree that an important event that drove the flowering of our intelligence was when our ancestors began to live in social groups. Decoding and developing the many subtle relationships among our fellows, and keeping track of these changing relationships over the course of the many decades of a typical human lifespan, was surely a major force shaping our minds.
But octopuses are neither long-lived nor social. Athena, to my sorrow, may live only a few more months—the natural lifespan of a giant Pacific octopus is only three years. If the aquarium added another octopus to her tank, one might eat the other. Except to mate, most octopuses have little to do with others of their kind.
So why is the octopus so intelligent? What is its mind for? Mather thinks she has the answer. She believes the event driving the octopus toward intelligence was the loss of the ancestral shell. Losing the shell freed the octopus for mobility. Now they didn’t need to wait for food to find them; they could hunt like tigers. And while most octopuses love crab best, they hunt and eat dozens of other species—each of which demands a different hunting strategy. Each animal you hunt may demand a different skill set: Will you camouflage yourself for a stalk-and-ambush attack? Shoot through the sea for a fast chase? Or crawl out of the water to capture escaping prey?
Losing the protective shell was a trade-off. Just about anything big enough to eat an octopus will do so. Each species of predator also demands a different evasion strategy—from flashing warning coloration if your attacker is vulnerable to venom, to changing color and shape to camouflage, to fortifying the door to your home with rocks.
Such intelligence is not always evident in the laboratory. “In the lab, you give the animals this situation, and they react,” points out Mather. But in the wild, “the octopus is actively discovering his environment, not waiting for it to hit him. The animal makes the decision to go out and get information, figures out how to get the information, gathers it, uses it, stores it. This has a great deal to do with consciousness.”
So what does it feel like to be an octopus? Philosopher Godfrey-Smith has given this a great deal of thought, especially when he meets octopuses and their relatives, giant cuttlefish, on dives in his native Australia. “They come forward and look at you. They reach out to touch you with their arms,” he said. “It’s remarkable how little is known about them … but I could see it turning out that we have to change the way we think of the nature of the mind itself to take into account minds with less of a centralized self.”
“I think consciousness comes in different flavors,” agrees Mather. “Some may have consciousness in a way we may not be able to imagine.”
IN MAY, I VISITED Athena a third time. I wanted to see if she recognized me. But how could I tell? Scott Dowd opened the top of her tank for me. Athena had been in a back corner but floated immediately to the top, arms outstretched, upside down.
This time I offered her only one arm. I had injured a knee and, feeling wobbly, used my right hand to steady me while I stood on the stool to lean over the tank. Athena in turn gripped me with only one of her arms, and very few of her suckers. Her hold on me was remarkably gentle.
I was struck by this, since Murphy and others had first described Athena’s personality to me as “feisty.” “They earn their names,” Murphy had told me. Athena is named for the Greek goddess of wisdom, war, and strategy. She is not usually a laid-back octopus, like George had been. “Athena could pull you into the tank,” Murphy had warned. “She’s curious about what you are.”
Was she less curious now? Did she remember me? I was disappointed that she did not bob her head up to look at me. But perhaps she didn’t need to. She may have known from the taste of my skin who I was. But why was this feisty octopus hanging in front of me in the water, upside down?
Then I thought I might know what she wanted from me. She was begging. Dowd asked around and learned that Athena hadn’t eaten in a couple of days, then allowed me the thrilling privilege of handing her a capelin. Perhaps I had understood something basic about what it felt like to be Athena at that moment: she was hungry. I handed a fish to one of her larger suckers, and she began to move it toward her mouth. But soon she brought more arms to the task, and covered the fish with many suckers—as if she were licking her fingers, savoring the meal.
A WEEK AFTER I LAST VISITED ATHENA, I was shocked to receive this e-mail from Scott Dowd: “Sorry to write with some sad news. Athena appears to be in her final days, or even hours. She will live on, though, through your conveyance.” Later that same day, Dowd wrote to tell me that she had died. To my surprise, I found myself in tears.
Why such sorrow? I had understood from the start that octopuses don’t live very long. I also knew that while Athena did seem to recognize me, I was not by any means her special friend. But she was very significant to me, both as an individual and as a representative from her octopodan world. She had given me a great gift: a deeper understanding of what it means to think, to feel, and to know. I was eager to meet more of her kind.
And so, it was with some excitement that I read this e-mail from Dowd a few weeks later: “There is a young pup octopus headed to Boston from the Pacific Northwest. Come shake hands (x8) when you can.”