The Soul of an Octopus: A Surprising Exploration into the Wonder of Consciousness

by Sy Montgomery

Here is an animal with venom like a snake, a beak like a parrot, and ink like an old-fashioned pen. It can weigh as much as a man and stretch as long as a car, yet it can pour its baggy, boneless body through an opening the size of an orange. It can change color and shape. It can taste with its skin. Most fascinating of all, I had read that octopuses are smart.

A giant Pacific octopus—the largest of the world’s 250 or so octopus species—can easily overpower a person. Just one of a big male’s three-inch-diameter suckers can lift 30 pounds, and a giant Pacific octopus has 1,600 of them. An octopus bite can inject a neurotoxic venom as well as saliva that has the ability to dissolve flesh.

Scott first came to the aquarium as a baby in diapers on its opening day, June 20, 1969, and basically never left. He knows almost every animal in the aquarium personally.

The giant Pacific octopus is one of the fastest-growing animals on the planet. Hatching from an egg the size of a grain of rice, one can grow both longer and heavier than a man in three years.

Its expression reminds me of the look in the eyes of paintings of Hindu gods and goddesses: serene, all-knowing, heavy with wisdom stretching back beyond time.

White is the color of a relaxed octopus; in cuttlefish, close relatives of octopus, females turn white when they encounter a fellow female, someone whom they need not fight or flee.

The massive “hafgufa” who “swallows men and ships and whales and everything it can reach” in the Old Icelandic saga Orvar-Odds is surely based on some kind of tentacled mollusk, and gave rise to the myth of the kraken.

Octopuses are highly individual. This is often reflected in the names keepers give them.

Octopuses realize that humans are individuals too. They like some people; they dislike others. And they behave differently toward those they know and trust.

The idea of octopuses with thoughts, feelings, and personalities disturbs some scientists and philosophers.

“There’s always an effort to minimize emotion and intelligence in other species,” the New England Aquarium’s director of public relations, Tony LaCasse, said after I met Athena. “The prejudice is particularly strong against fish and invertebrates,” agreed Scott.

The octopus had been slipping out of her tank and eating the flounder! When the octopus was discovered, Scott said, “she gave a guilty, sideways look and slithered away.”

One day the shark attacked one of the spotted eels in the tank and was swimming around with her victim’s tail protruding from her mouth. “One of the divers who knew Bimini well wagged his finger at her, and then bopped her on the nose,” Tony told me. In response, Bimini instantly regurgitated the eel.

an octopus is put together completely differently, with three hearts, a brain that wraps around its throat, and a covering of slime instead of hair. Even their blood is a different color from ours; it’s blue, because copper, not iron, carries its oxygen.

Henry Beston writes that animals “are not brethren, they are not underlings” but beings “gifted with extensions of the senses we have lost or never attained, living by voices we shall never hear.” They are, he writes, “other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendor and travail of the earth.”

Three fifths of octopuses’ neurons are not in the brain but in the arms. If an arm is severed from an octopus’s body, the arm will often carry on as if nothing has happened for several hours.

While on a trawler in the English Channel, an octopus who had been caught and left on deck somehow managed to slither from the deck, down the companionway, to the cabin. Hours later, it was found hiding in a teapot.

On closer inspection, the banana peel turned out to be a healthy, fist-size red octopus. The security officer followed the wet slime trail and replaced the octopus in the exhibit it had come from. But here’s the shocking part: The aquarium didn’t know it had a red octopus living in its Shale Reef exhibit. Apparently the octopus hitchhiked there as a juvenile, attached to a rock or sponge added to the exhibit, and grew up at the aquarium without anyone knowing it was there.

At the Seattle Aquarium, Sammy the giant Pacific octopus enjoyed playing with a baseball-size plastic ball that could be screwed together by twisting the two halves. A staffer put food inside the ball but later was surprised to find that not only had the octopus opened the ball, it had screwed it back together when it was done.

When the two crabs started fighting, Truman became too excited to bother with the locks. He poured his seven-foot-long body through the two-by-six-inch crack Guinevere had made. Visitors to his exhibit found the giant octopus, suckers flattened and facing out, squeezed into the tiny space between the walls of the fourteen-cubic-inch middle box and the six-cubic-inch one inside it.

As a teenager in the 1950s, she had lived with her parents among the Bushmen in Namibia, which she wrote about in her first best seller, The Harmless People; she spent the next six decades researching and writing nonfiction books about lions, elephants, tigers, deer, wolves, and dogs, as well as two Paleolithic novels.

“An aquarium without an octopus,” as the Victorian naturalist Henry Lee of Brighton, UK, wrote in 1875, “is like a plum pudding without plums.”

Nicotine is a known insect repellent, and toxic to many other invertebrates.

“All men,” wrote Plutarch, “while they are awake, are in one common world; but each of them, when he is asleep, is in a world of his own.”

Hatching from an egg the size of a grain of rice weighing three-tenths of a gram, a baby giant Pacific octopus doubles its weight every eight days until it reaches about 44 pounds, then doubles its weight every four months until maturity.

the octopus might hide, squeeze into a corner, or hold fast to some object and refuse to let go. Some would allow themselves to be captured, only to use the net as a trampoline. They’d leap off the mesh like acrobats and dive to the floor—and then run for it.

Some were so friendly, Alexa said, “they would lift their arms out of the water like a dog jumps up to greet you”—or like a child who wants to be lifted up and hugged.

Some of these little organs seem to be passive, but other iridophores appear to be controlled by the nervous system. They are associated with the neurotransmitter acetylcholine, the first neurotransmitter to be identified in any animal.

Acetylcholine helps with contraction of muscles; in humans, it is also important in memory, learning, and REM sleep.

In octopuses, more of it “turns on” the greens and blues; less creates pinks and golds. The topmost layer of the octopus’s skin contains chromatophores, tiny sacks of yellow, red, brown, and black pigment, each in an elastic container that can be opened or closed to reveal more or less color. Camouflaging the eye alone—with a variety of patterns including a bar, a bandit’s mask, and a starburst pattern—can involve as many as 5 million chromatoph...

the octopus can also voluntarily control its skin texture—raising and lowering fleshy projections called papillae—as well as change its overall shape and posture.

Another measure scientists use to assess brain power is to count neurons, the mainstay of the brain’s processing capabilities. By this measure, the octopus is again impressive. An octopus has 300 million neurons. A rat, 200 million. A frog, perhaps 16 million. A pond snail, a fellow mollusk, at most, 11,000. A human, on the other hand, has 100 billion neurons in the brain.

Still, the octopus eye and our own are strikingly similar. Both have lens-based focusing, with transparent corneas, irises that regulate light, and retinas in the back of the eye to convert light to neural signals that can be processed in the brain. Yet there are also differences. The octopus eye, unlike our own, can detect polarized light. It has no blind spot.

Human eyes have three visual pigments, allowing us to see color. Octopuses have only one—which would make these masters of camouflage, commanding a glittering rainbow of colors, technically color-blind.

the skin of the octopus’s close relative, the cuttlefish Sepia officinalis, contains gene sequences usually expressed only in the retina of the eye.

Jennifer, a psychologist at the University of Lethbridge in Canada, is one of the world’s leading researchers on octopus intelligence; Roland, a biologist at the Seattle Aquarium, is another.

They also told us about Paul, the octopus from Sea Life Oberhausen, in Germany, who correctly predicted the outcomes of the 2010 FIFA World Cup soccer matches seven times in a row.

when I saw Octavia again, she held on to me, gently but firmly, for an hour and fifteen minutes. I stroked her head, her arms, her webbing, absorbed in her presence. She seemed equally attentive to me. Clearly, each of us wanted the other’s company, just as human friends are excited to reunite with each other.

You can tell by looking at the tip of the third right arm. If the arm has suckers all the way to the tip, you have a female. If not, the appendage is referred to as the hectocotylized arm, and the animal is male.

This is the specialized organ for placing the spermatophore inside the female. (But he doesn’t put it between her “legs,” or arms, because that’s where her beak is. He puts it in her mantle opening—or, as Aristotle explained it, he “has a sort of penis on one of his tentacles . . . which it admits into the nostril of a female.”)

Everywhere, impossible changes unfold before our eyes. In the leafy sea dragon tank, the male gives birth to the babies, who come shooting out of a belly pouch that is like an opossum’s. Among the corals of the Giant Ocean Tank, a species of fish called the bird wrasse starts out life as a black or brown female, then turns into a male.

Hormones and neurotransmitters, the chemicals associated with human desire, fear, love, joy, and sadness, “are highly conserved across taxa,”

Research including Jennifer’s shows that wild octopuses choose to spend 70 to 90 percent of their time crammed into tight dens.

Neuroscientist Antonio Damasio briefly mentions anemones in his book on consciousness and emotion, The Feeling of What Happens. He does not argue that anemones possess consciousness; but, he writes, in their simple, brainless behaviors, we can see “the essence of joy and sadness, of approach and avoidance, of vulnerability and safety.”

She gestured for me to hold my nose and blow—a trick for equalizing pressure called the Valsalva maneuver.

I also used the Frenzel maneuver, another way of opening the eustachian tubes, by moving the jaw around like a snake trying to swallow something bigger than its head.

The ancient Spartans believed that cold water is good for everything, including your hair. Water temperatures in this range do, in fact, cause physiological changes—one of which is known as the cold-shock response,

The ocean, for me, is what LSD was to Timothy Leary. He claimed the hallucinogen is to reality what a microscope is to biology, affording a perception of reality that was not before accessible.

Her chemoreceptors can pick up chemical information from a distance of at least 30 yards. One researcher found that octopus suckers were 100 times more sensitive tasting chemicals dissolved in seawater than a human tongue tasting flavors dissolved in distilled water.

Kali was extremely lucky to have lived as long as she did. Most octopuses die as paralarvae. Only two in 100,000 hatchlings survive to sexual maturity—otherwise the sea would be overrun with octopuses.