Kraken
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But if researchers come to believe that the giant Pacific octopus is an intelligent being, then the theory that intelligence depends on social interaction will be less viable. The giant Pacific octopus is a solitary animal, so much so that after the mother oversees the hatching of her offspring, she dies. There is no ongoing teaching. Supposedly, everything the newly hatched octopus needs to survive is hardwired into its brain. Yet the animal clearly learns. Throughout its short life, the octopus continuously improves its ability to solve novel and challenging problems like opening jars. These are problems that it might never encounter naturally in the ocean. As we continue to learn about cephalopods, it’s likely that our understanding of what it means to be intelligent will expand.
However, judging an animal’s “intelligence” by its ability to learn is a dangerous thing, because an animal’s ability to learn will depend greatly on what, exactly, is the relevance of what it’s learning. Most animals can learn fairly easily what’s edible and what isn’t, but many species will have trouble with math. We humans cannot change the color or texture of the skin on our arms, but that’s very relevant if you’re an octopus—so, most likely, we would appear dazed and doltish to an octopus or a squid.
I asked Bill Gilly if he agreed with Scott Brady’s joke that squid are the jocks of the cephalopod world, while the octopuses are the intellectuals.
Gilly returned the joke.
“No, I would not completely agree…. There are many wimpy, girlie-man squid that are flabby and not what we ordinarily think of as highly athletic,” he responded.
He brought up the possibility that we vertebrates might simply be self-centered, or possibly even rather conceited. Gilly said: “I think it is we who are not intelligent enough to devise an IQ test for cephalopods that does not associate humanoid-like activity with intelligence.”
Then he stood up for his own research subjects, who, in his opinion, get a bum rap in the octopus-versus-squid discussion. Gilly maintains that humans in general prefer octopuses over squid because we see ourselves as having more in common with the lifestyle choices made by octopuses: “An octopus lives on a two-dimensional substrate, can travel a well-practiced route to go to work on its night-shift job, typically has a house, regularly takes out its trash, and loves to eat crab. So we think the octopus is intelligent because it behaves like we do.”
In other words, ho-hum. Not such a challenging lifestyle. We can relate to the octopus’s calm, middle-class existence better than to a squid’s mysterious, gypsylike wanderings through the ocean depths. The octopus seems to be a thoroughly modern being, willing to trade excitement for security. From the viewpoint of animals (and people) who live adventurous lives, the octopus opts for boredom.
Said Gilly: “A squid, on the other hand, especially one like Dosidicus, lives in a three-dimensional world with boundaries set by temperature, light, oxygen, and salinity rather than physical objects. They do not have permanent places of residence and are nomadic hunters. They eat mesopelagic [mid-level oceanic] organisms that most people don’t even know about.
“In short, they are a life-form quite alien to us, and so I think we tend to think of them as being less advanced or intelligent. Again I think that attitude reflects our limitations of perception and understanding. This is just the anthropomorphic nature of man.”
Take that, you octopus fans!
Then Gilly concluded: “My less spiritual answer would be that both the squid and the octopus have very large brains…. We don’t know much at all about how the cephalopod brain works—there simply have not been many people studying cephalopod brain structure and function in comparison to the vast number studying vertebrates over the past hundred years. Maybe someday we’ll learn enough to answer your simple question from a better platform of knowledge.”
Octopus man James Wood agrees. “I used to think that the answer to the question was octopus. But now I think that octopus are just easier to manage. Squid are difficult,” he said. Most species of squid (except for Margaret McFall-Ngai’s “couch potato” Hawaiian bobtail squid) cannot be kept alive for long in captivity. The squid’s giant axon, which has helped us understand our own brains, evolved as a fight-or-flight mechanism that allowed them to quickly scoot away from potential harm. Whenever something unexpected happens—someone walks near the squid tank, for example—that giant axon sends a message to the muscles involved in swimming, and the animal immediately darts away. In a tank, this tendency to dart means that the animal may quite often slam into the side of the tank and harm itself.
Squid can learn to overcome this reaction somewhat, as shown by several scientists like the Georgia Aquarium’s chief science officer, Bruce Carlson (who trained some squid to feed from his hand when he was in Hawaii), but no one has ever been able to habituate a squid to the degree that Wilson Menashi has habituated the New England Aquarium’s giant Pacific octopus, Truman. It’s unlikely, given the squid’s biology, that a squid will ever playfully interact with a human.
What does that mean about the squid’s intelligence? I asked Wood’s opinion.
“Let’s say you have two people and one of them is really good at math, and the other is an amazing artist,” he answered. “Which one is more intelligent? And does your answer depend on whether you’re an art teacher or a math teacher?”
This more flexible view of animal intelligence is an emergent phenomenon. The old view was hierarchical with human beings (surprise, surprise) at the top and with the rest of animal life in descending rank. Today animal researchers look less at “levels” of intelligence—“smarter than”—than at styles of intelligence and expressions of a variety of intelligences.
I spoke about this with neuroethologist Paul Patton on the phone one crisp early October day from his office at Bowling Green State University in Ohio. Patton studies the lateral line sense, the sense of water flow, possessed by fish but lacked by humans. Fish can perceive the world around them by using this sense. Even fish that are blind seem to have this alternative ability to “see” their surroundings in this way. It’s possible to imagine that a fish would perceive us as quite dim-witted if its only knowledge of us was when we were in the water swimming alongside it.
“Are fish smarter than us, then?” I asked.
“In the sea, perhaps,” Patton answered.
With this change in view, the science of teasing apart aspects of another species’ intelligence has also changed. As Patton explained in “One World, Many Minds,” an article written for Scientific American, “complex brains—and sophisticated cognition [thinking]—have evolved from simpler brains multiple times independently” in groups of animals that are, evolutionarily, quite different from each other. Patton particularly noted cephalopod brains.
Of course, if you consider the similarity between the human and the cephalopod neuron, the idea that intelligence could evolve in many different kinds of animals, social or otherwise, doesn’t seem quite so surprising. As with eyes, the first step in developing the basic framework has been there all the time. Previously, we just didn’t have enough knowledge ourselves to understand that fact.
That’s probably why a respected scientist like Alfred Romer could write in 1955 that the brains of birds, complex though they are, allowed for “little learning capacity.” If he were alive today, he’d probably be embarrassed by his statement, given all the recent discoveries about how truly brilliant some birds are—if studied in their own environmental niches. Today researchers like Bernd Heinrich in Mind of the Raven have shown that some bird species can think and reason. Ravens, Heinrich claims, have even designed “an elegant system of food sharing.” Traditionalists have long claimed that what sets humans apart from other animals is that we have “consciousness.” Heinrich defines that quality as “the routine mental representation of things and events not directly before the senses,” and he believes that ravens possess this ability.
One thing is certain: The pattern of learning in birds is sometimes similar to our own, but
not always. As researchers have pursued this avenue, they have discovered that learning in any species is vastly more complicated than twentieth-century scientists realized. Recently, at his animal behavior lab at the City College of New York, researcher Ofer Tchernichovsky discovered one example of just how complex learning can be. He looked at the intricate process by which male zebra finches learn to sing their songs. He found that learning in the zebra finch is a mysterious and many-layered process.
I visited Tchernichovsky’s lab to see the finches.
He showed me one of the most amazing animal videos I’ve ever seen. It showed a male zebra finch who had been isolated from other finches throughout its life. The young bird had never heard another finch sing.
As I saw in the video, at a certain point in the young bird’s life, Tchernichovsky gave him access to a recording of a mature male singing. To hear the recording, the young bird had to use an ingenious kind of “switch,” a string that he could pull with his beak. At first the young bird was somewhat agitated by the string, a new item in his cage. But then, using his beak, he yanked on it. When the young bird heard the older male finch’s song for the first time, he seemed to go into a state of shock. His entire body seemed to go into a trance, as if he had been hypnotized. The bird immediately sank down on his perch and fell into a short, deep sleep. The song was a powerful lullaby.
Then, when the bird woke after a full night’s sleep, he began to try to sing the song he had heard. His first attempts weren’t that good. But over time, after repeatedly hearing the song, and after repeating and repeating and repeating the notes, and after night after night of sleeping—a short nap wasn’t enough—his song became more and more like the song of the older male.
“The bird cannot learn to sing this song without the full night’s sleep,” Tchernichovsky told me.
Tchernichovsky has uncovered layer upon layer of complexity in the song-learning process. He has found out that male birds living near each other and hearing each other then develop a cultural song. But he has also found that individual birds within the group may develop their own unique version of the cultural song. And he has found that over the course of several generations, an isolated group’s song will gradually come to resemble more and more the generic “zebra finch song” shared by all male zebra finches. In other words, the basic template for the correct song must be somehow encoded in the bird’s brain, just as many researchers believe the basic template for language is encoded in human brains. But there is also room for culture and for individuality.
Is there such a thing as squid culture? Are cuttlefish capable of learning? Is there room for individuality among octopuses? Are they self-aware or even conscious, whatever that might mean? Certainly, the evolutionary biologist and respected animal behavior researcher Martin Moynihan thought so. Moynihan studied the intelligence and social behavior of primates and of birds, but he was also interested in cephalopods, long before others in his field. He wrote before his death at sixty-eight in 1996 that octopuses, squid, and cuttlefish are capable of taking actions that “are overt and decisive. I cannot believe that they are not deliberate and in some sense conscious.” Moynihan had spent countless hours diving and following schools of Caribbean reef squid. He concluded that the behavior of individual animals within the school seemed self-aware and even intentional. But how would you find out?
Most of the researchers I spoke with during the writing of this book do suspect that cephalopods are exceptionally intelligent and that they are certainly the most highly developed of invertebrate species. A few suggest that they may be the most intelligent animals in the sea, save for marine mammals. Several researchers believe that intelligence in cephalopods is only logical, since intelligence is a strategy for successful predation, like the teeth of the saber-toothed tiger or the snapping jaws of a crocodile. An octopus, for example, must hunt for its food, and since the hunt involves active investigation and searching for food under rocks and in nooks and crannies like an Easter egg hunt, the evolution of some type of intelligence shouldn’t be surprising, despite its asocial lifestyle. The problem, of course, is that we don’t have a clear and commonly accepted definition of “intelligence.”
I asked a number of scientists: What is it?
One of my favorite comments came from UCLA neuroscientist David Glanzman. Glanzman studies learning and memory on a cellular level. He uses Aplysia, a simple mollusk related only distantly to the complex cephalopods. Aplysia, commonly called a “sea hare,” has only 20,000 neurons. The animal’s simple neural systems make it easier to study the complexities of learning and memory than if he were using cephalopods.
I asked him about learning, memory, and thinking in octopuses.
“I sort of look at the octopus as though it were a Martian,” he said. “If we saw a Martian repairing a spaceship, we would say: ‘Look, there’s an intelligent being!’”
We would do that, he explained, because we would recognize that repairing a spaceship took intelligence. But it’s equally possible that the things that cephalopods do require intelligence but we don’t recognize it as such.
He said: “Nobody knows how cephalopod intelligence works. And that’s what I think would be a really useful scientific enterprise. I come back to the Martian example. If you saw a Martian and you saw intelligent behavior, and you got a glimpse of his brain, my guess is that his brain would not be like ours. So, you would want to know, how does it do the things that we do with a totally different brain? Intellectually, I think this is a fascinating question. I want to know how intelligent these animals are. How do they do it? How do their brains do it?”
Glanzman first became fascinated with octopuses when he visited a scientist at the Beaufort Laboratory in North Carolina. The scientist had split the brain of an octopus and had trained the animal so that when the octopus perceived a white ball on one side of the brain, it grabbed the ball and was rewarded with food. When the octopus was presented with the same ball on the other side of the brain, it received a shock if it grabbed the ball.
“I was stunned by how intelligent that animal was,” Glanzman said. When the positively reinforced side of the brain was shown the ball, “one of its arms just shot out and grabbed the white ball. But when it saw the ball with the other side of its brain, it literally cowered.”
This work was enough to keep Glanzman interested for the next several decades.
“Does this have a cognitive element?” he wondered as we talked. “Does this animal ‘plan’ things in its life? By this example alone, you wouldn’t know that.”
Glanzman believes that by studying questions like these, we would learn important things about our own intelligence and about the evolution of intelligence. “Look: Here’s something that has cognition and that seems to be similar to us in that, and it has a brain that’s structured completely differently from ours. If that’s true—does that enhance the possibility that there might have been cognitive beings that arose extraterrestrially? And maybe that means that if you have life, eventually, if you give it enough time, you would have cognition,” he said.
“Do I believe that parallel evolution of intelligence is possible? Absolutely! Absolutely!”
Glanzman’s enthusiasm for considering the possibility of cephalopod intelligence took me by surprise, but in fact, scientific excitement over the possibility seemed to be nearly universal. Yet despite this excitement, very few researchers are devoting careers to studying the question. In fact, it’s considered a scientific backwater. Because of the difficulty of formulating well-thoughtout research protocols, very little funding has been made available.
It’s not easy to put yourself in the mind of an animal with a different brain, even an animal as familiar to us as the dog. One researcher who seems to have somewhat accomplished that goal is Marc Bekoff, retired from the University of Colorado at Boulder. Whereas James Wood imagined a test for human intelligence designed by an octopus, Bekoff asked himself: What if a dog designed a test for self-recognitio
n? For much of the twentieth century, it was assumed that primates were “higher” animals because they could recognize themselves as unique individuals, separate from the rest of the world. Bekoff decided to find out if a dog could also recognize itself as a unique individual.
Prior to Bekoff’s experiment, self-recognition studies had primarily involved having an animal look into a mirror. If the animal recognized its own image, it was said to have “self-recognition,” a quality that was considered essential for higherlevel thinking. Scientists put a dot on the forehead of a primate study subject, then placed a mirror in front of the animal. Seeing the dot in its reflection, the primate usually touched the dot on its own forehead. Other species tested did not do this. Therefore, reasoned scientists, primates recognize the image in the mirror as being their own, and thus possess a sense of self.
Dogs do not do this. Therefore, scientists reasoned, dogs do not understand themselves as unique individuals. Bekoff disagreed with this conclusion. He reasoned that dogs have fewer neurons involved with vision than do we. And they can’t see in color. Therefore, they don’t care about vision in the same way that primates care about vision. On the other hand, smell is more important to dogs than it is to primates. Smell, Bekoff reasoned, is something that dogs do care about.
Bekoff decided to test his own dog, Jethro. Jethro certainly behaved as though he understood himself to be a unique individual. He knew what he wanted. He knew what would cause him pain. He knew what he liked to eat. He seemed to have a strong sense of self.
Bekoff knew, as would anyone who’d ever spent time around a dog, that dogs may not care about mirrors. But they do care about smells. A lot. Try taking a dog for a walk where other dogs have recently roamed. You won’t get far. This is not surprising. Whereas we have only about 5 million receptors in our noses connected to neuron bodies in our brains to help us differentiate smells, a dog has more than 200 million.