National Geographic Society Newsroom

The Slightly Disturbing Science of Squid

Squid are known to most people as seafood, delicious in a wide range of wholesome recipes. Or we may know them from myths and legends–or horror movies–in which they star as monsters of the deep. The squid is a cephalopod, related to the octopus, cuttlefish and the nautilus. Cephalopods are among the oldest and most...

Squid are known to most people as seafood, delicious in a wide range of wholesome recipes. Or we may know them from myths and legends–or horror movies–in which they star as monsters of the deep.

The squid is a cephalopod, related to the octopus, cuttlefish and the nautilus. Cephalopods are among the oldest and most successful animals that have ever lived. They have survived hundreds of millions of years.

“When [squid] stare so intensely into our human eyes, they are seductive.”

“When the animals stare so intensely into our human eyes, they are seductive,” writes Wendy Williams in her new book about squid. “With eight or more dangling arms and tentacles encircling their mouths, with the ability to change color and shape in milliseconds, with suckers as dexterous as our fingers and thumbs, and with eyes that are better than ours in some ways, they are enticingly, bewitchingly, exotically alien.”

I read Kraken: The Curious, Exciting, and Slightly Disturbing Science of Squid (Abrams; U.S.$21.25)  in one well-spent weekend afternoon.

It’s not only wonderfully written, but it is thoroughly researched. The book is alive with quotes and stories from the many people Williams visited in the field.

The extensive bibliography is what you’d expect of a thesis, and in some ways this book is a wonderful education about a very mysterious animal.

For all its weirdness, it turns out that squid and humans share aspects of our eyes, nervous system, and perhaps even intelligence. In some respects they are superior to us, certainly within their marine world, but also perhaps in their ability to adapt and survive whatever the planet throws at them.

I asked Wendy Williams to share with us a few highlights of her compelling book.


You approached this book as an investigative journalist. Did you ever imagine that cephalopods were so complex and interesting?

In fact, in another life, I am an investigative journalist. All that really means is that I find facts interesting. And an obsession with knowing as much as possible.

And the facts, just the facts, about squid and other cephalopods were definitely overwhelming. Who knew, for example, that the blanket octopus behaves kind of like Zorro? This guy can pull the poisonous tentacles off a Portuguese man-o-war and wield those tentacles like a sword to ward off predators. It’s evolved its own immunity to the poisonous pseudo-jelly.

What motivated you to write a book about squid? Were you surprised by how much there was to know about it?

Well, I always want to understand everything about a subject I want to write about. Only a smidgen of what I read ends up in print, but I’m always in a panic that I might miss something that readers might find fascinating.

With these guys, though, I pretty quickly had to accept the fact that no one — not even lifelong teuthologists — could possible know everything. After all, cephs have been around for hundreds of millions of years. When the dinosaurs died out, the cephalopods lived on.
They must be on to something.

Explain the title Kraken. Apparently the sailors’ tales of giant squid pulling down ships were just that, tales?

Who knows? I sure don’t, since I wasn’t there.

The animals in the ocean seem to be much smaller today than in earlier centuries. No one is quite sure why. But that does mean that some cephs may well have been much bigger than they are today.

Our largest giant Pacific octopuses seem to be no more than about 100 pounds. But there are tales from the early 20th century about the species reaching as much as 600 pounds. True or false? No one knows.

Nonetheless, squid are pretty fearsome predators. They’re cannibals. What are some of their weapons?

All cephalopods are hunters. The Humboldt squid out on the American west coast is sometimes called “the wolf of the ocean.”

And Tom Mattusch, captain of the Huli Cat out of California’s Pillar Point Harbor, told me that he once caught two squid on one lure. Apparently squid number one got hooked and squid number two took advantage by trying to eat the first animal. When Mattusch pulled them up, he thought at first he’d caught some kind of weird genetic monster with many more than 10 arms and tentacles. Then he realized the truth: Two in One.

To me, the most fearsome aspect of all the decapods — the cephs with eight arms and two feeding tentacles — is the speed with which those tentacles can flash out and capture prey. I stood watching this over and over at the Georgia Aquarium. The aquarist dropped minuscule bits of food into a tank filled with baby cuttlefish. They might have been small, but their tentacles moved with the speed of a laser.

No wonder our ancestors evolved so long ago limbs that allowed us to escape the water and walk on dry land. I’ll take a lion to a large squid any day.


I was intrigued by the account of the mother starving to death to protect her offspring. Squid reproduction is somewhat bizarre, is it not?

Well, I guess the answer to that depends on your point of view. The squid seem to like it.

One thing though — that story was about a mother giant Pacific octopus. Her story is full of pathos, and it broke my heart.

Most squid, on the other hand, couldn’t care less about their offspring.

You describe the eyes of some of the biggest squid as being the size of dinner plates. Their eyes are sophisticated and in some ways better than ours. You seem to have been mesmerized by what you saw in their eyes. Can you talk a little about that.

The big eyes I found positively creepy. Like watching a horror movie. But the eyes of the cuttlefish were mesmerizing. In the ocean, divers love finding these animals, because it’s possible then to watch them watch you.

And we primates absolutely adore making eye contact with other living things.

The skin of a cephalopod can be “smart.” What is the secret of their invisibility cloak?

You know, three-fifths of a ceph’s neurons are not in the “head” per se, but in the arms and tentacles. One reason why this is so is because many of the skin cells that can change color are operated by several sets of muscles, and each individual muscle is connected to a neural cell capable of moving that muscle. So their appendages are a lot more complicated than ours.

I liked your description of squid having to be wary of predators in three dimensions. What are some of their other tricks to avoid being eaten?

There are some species that can emit ink that forms a pseudomorph — an imitation of the squid itself. Then, hopefully from the squid’s point of view, the predator will go after the fake, inky squid and not the real one.

Why do squid need three brains? What are the surprises of their nervous system and intelligence?

We know next to nothing about their intelligence — except that there’s “something” there.

My friend James Wood, now with the Waikiki Aquarium, explained it this way:

Imagine an octopus trying to develop a test for human intelligence.

So the octopus says: “Well, let’s try to find out how smart these humans are, because they show a little bit of promise in a very few ways.”

So the research question turns out to be: “How Many Color Changes Can Your Severed Arm Produce in One Second?”

The octopus is going to turn out to be might disappointed, isn’t he?

Squid have properties that can help cure human diseases and conditions. What are some of those and what might be developed?

Well, squid and humans share a whole lot of very basic biology — like the neuron, for example. By studying squid, we’ve learned that inside the axon of a human neuron is a city that never sleeps. It’s amazing. My friend Joe DeGiorgis, a researcher at the Marine Biological Laboratory in Woods Hole, Massachusetts, is studying all the different kinds of “motors” inside our brain cells that follow very clearly laid out roadways in our cells and tug along their loads, like stevedores. The more Joe and his colleagues learn about this basic biology, the more we know about ourselves.

Very cool.

Do you think squid will survive what humans are inflicting on the planet?

Well, they’ve been around almost from the beginning. I’d say they were tough old birds, but birds were not even close to evolving when the cephalopods first appeared. Some scientists think that the first mollusks, precursors to squid, appeared on the planet before the Cambrian Explosion, 542 million years ago.

On the other hand, recent research funded in part by my own funding organization, The Ocean Foundation, suggests that an unusual sequence of giant squid strandings off the coast of Spain almost a decade ago may be the result of a lot of human-generated undersea noise.

Other than reading your book, what would you tell budding marine biologists interested in researching squid? What do we still need to know about these animals and how can they be helped to continue their long journey on Earth?

Go for it! Definitely. We’ll never really understand these animals, so there will always be a research question out there for you.



Wendy Williams is the author of five books, including the recent Cape Wind. Her science journalism has appeared in major scientific publications like Scientific American, Science and Conservation Biology. Her reporting has also appeared in the Wall Street Journal, The New York Times, the Boston Globe, the Boston Herald, the Christian Science Monitor, and many other newspapers. Her magazine writing is equally diverse, ranging from Audubon and National Wildlife to the Ladies Home Journal. She is at work now on a book about coral reefs.

12418031_10153900711084116_8462971761216697621_nDavid Braun is director of outreach with the digital and social media team illuminating the National Geographic Society’s explorer, science, and education programs.

He edits National Geographic Voices, hosting a global discussion on issues resonating with the Society’s mission and major initiatives. Contributors include grantees and Society partners, as well as universities, foundations, interest groups, and individuals dedicated to a sustainable world. More than 50,000 readers have participated in 10,000 conversations.

Braun also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship

Follow David on Facebook  Twitter  LinkedIn

About National Geographic Society

The National Geographic Society is a global nonprofit organization that uses the power of science, exploration, education and storytelling to illuminate and protect the wonder of our world. Since 1888, National Geographic has pushed the boundaries of exploration, investing in bold people and transformative ideas, providing more than 14,000 grants for work across all seven continents, reaching 3 million students each year through education offerings, and engaging audiences around the globe through signature experiences, stories and content. To learn more, visit or follow us on Instagram, Twitter and Facebook.

Meet the Author

Author Photo David Max Braun
More than forty years in U.S., UK, and South African media gives David Max Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn