The Honorary Vertebrate
Despite being mollusks, like clams and oysters, these animals have very large brains and exhibit a curious, enigmatic intelligence.”
Peter Godfrey-Smith, professor of philosophy and author of Other Minds: The Octopus, the Sea, and the Deep Origins of Consciousness
An octopus named Paul gained global fame in 2010 when he correctly predicted the outcome of eight World Cup soccer matches, including the final. He would choose between two containers, each holding one of the competing teams’ national flags. Of course, this was just a fluke, but the story gained global attention in part because it fit with emerging scientific evidence about the surprising intelligence of octopuses.
It’s easy to imagine that orangutans, chimpanzees, dolphins, whales, and elephants are highly intelligent animals, with rich emotional lives and complex social networks. Even though we may never have seen these creatures in the wild, we have a comfortable familiarity with them, telling our children stories about Babar, Free Willy, and Curious George.
An octopus is more alien to us. On the tree of evolution, humans and octopuses diverged about 600 million years ago. It shows. They have eight arms equipped with hundreds of flexible suckers that can not only grip but also taste. Technically, octopuses are mollusks, like oysters, clams, and snails, yet through evolution they have shed their external shell. They have a beak, like a parrot. Cells that sense light are embedded in their skin. Different species of octopus range in size from the pygmy octopus, full grown at less than an ounce, to the Pacific giant octopus, which can weigh more than 200 pounds. They employ jet propulsion, shooting water through a funnel to move, dig holes in sand, or target pests. They can grow back an arm, if one gets detached. They have three hearts and blue blood. Some octopus species can shoot jets of ink, creating clouds that enable them to disappear. Others have venom that they inject into their prey. Australia’s blue-ringed octopus can kill a human. Perhaps most strikingly, they challenge our basic ideas about the mind-body relationship. As well as a centralized brain, the octopus has a decentralized brain, enabling the arms to act independently.
And yet, for all the profound differences, there is something engaging and attractive about octopuses. Maybe it’s their eyes, which are nearly identical in structure to human eyes. Canadian zoologist N.J. Berrill called this similarity “the single most startling feature of the whole animal kingdom.” The big difference is that while we have round pupils, octopuses have horizontal slits.
The attraction could also be because octopuses are really smart and have individual personalities. Octopuses have hundreds of times more neurons than any other invertebrate. In fact, with an estimated 500 million neurons, they are well ahead of mice and rats and very close to cats (700 million).
The more scientists learn about these eight-armed invertebrates, the more remarkable they seem. Their ability to escape from captivity is legendary. Octopuses held in aquariums are infamous for escaping their tanks at night, climbing into other tanks to eat a few snacks, and then returning to their tanks, leaving aquarium employees baffled the next day. Thanks to the absence of bones, they can squeeze their entire bodies through amazingly small cracks and holes. An octopus can sneak into a fisherman’s crab trap, eat all the crabs, and leave.
Inky was a wild octopus found tangled in a crayfish trap by a fisherman and taken to the National Aquarium of New Zealand in the coastal city of Napier. For two years, Inky was one of the aquarium’s main attractions, but in 2016 he disappeared. He took advantage of a gap at the top of his enclosure left by a negligent maintenance worker, got out of his tank, moved across the floor, found a fifteen-centimetre-wide drainpipe that led back to the ocean, squeezed his way into it, and escaped. And when flounders in a special research project at the same aquarium began disappearing from their tank, another octopus was identified as the culprit, despite being in a different tank over four metres away.
Octopuses are tool users. They seek out rocks to narrow and camouflage the entries to their dens. The coconut octopus hides in shells, and got its name because it sometimes carries a coconut shell around to serve as an emergency shelter. Octopuses also have the extraordinary ability to change their shape, skin colour, and texture to camouflage themselves against their surroundings. Almost instantly, their skin can transform to mimic sand, coral, algae, or rock. They can dismantle Lego and even open the childproof lids on pill bottles. They like to play with toys and improvise their own games. One octopus used jets of water to push a bottle in circles around her aquarium. They can navigate mazes, solve problems such as unlocking a series of boxes to access food, and remember the solutions. An octopus at the University of Otago in New Zealand figured out that she could turn off a light outside her tank by shooting jets of water at it. Replacing the light became so expensive that the university returned the octopus to the ocean.
Jennifer Mather, a psychologist at the University of Lethbridge and author of Octopus: The Ocean’s Intelligent Invertebrate, believes that these animals have personalities, and that they can be shy or bold, active or passive, emotional or reserved. In the 1950s, a Harvard scientist named Peter Dews conducted an experiment with three octopuses named Albert, Bertram, and Charles. Albert and Bertram quickly learned that if they pulled a lever, a light would come on and they would receive a piece of sardine. Charles also figured this out, but was more interested in the light and the lever. He wrapped his tentacles around the light and pulled it into his den. He also spent much of his time shooting jets of water at Dews. Finally, Charles pulled on the lever with such force that it bent and eventually broke, prematurely terminating the experiment.
Other experiments have confirmed that octopuses can recognize and distinguish specific humans. Scientists also believe that the changing colours of an octopus reflect its state of mind, like a mood ring. A giant Pacific octopus is white when relaxed and red when agitated or excited.
The octopus is so intelligent that in 1993 it became an “honorary vertebrate,” the only invertebrate to be given special protection under the British law governing the licensing of animal experiments. In 2010, the European Union placed strict limits on research experiments involving octopuses because “there is scientific evidence of their ability to experience pain, suffering, distress and lasting harm.”
Chapter 1: Breakthroughs in Understanding Animal Minds
“Given that we now know that we live in a world of sentient beings, not one of stimulus-response machines, we need to ask, how should we treat these other emotional, thinking creatures?”
Virginia Morell, Animal Wise
Humans often forget, or deliberately ignore, the fact that we are animals. Consider the sign commonly posted on doors at stores and malls: “No animals allowed.” If taken literally, this would be catastrophic for business! Or take the expression “behaving like an animal.” Well, how else is a person supposed to behave?
As recently as the 1970s, the prevailing wisdom was that non-human animals were automatons that merely reacted instinctively to external stimuli. Then along came Dr. Donald Griffin, an American zoology professor who originally rose to prominence in 1944 when he figured out that bats use echolocation to navigate. In 1976, after decades of observing different species in labs and in the wild, Griffin suggested that scientists should study animal minds and attempt to learn how they think. Griffin maintained that animals are conscious, even if they might think about different things and in different ways than humans. He opened the door to a whole new field of science called cognitive ethology—the study of the minds, awareness, and, yes, even the consciousness of non-human animals.
Since Griffin issued his challenge, there has been an extraordinary proliferation of scientific research about the minds of animals, overturning many of our previous understandings. There are currently more scientists observing and studying more species than at any time in history. Peer-reviewed scientific articles on animal cognition and capabilities are being published at an unprecedented rate. There have been breakthroughs in our understanding of animal brains through the fields of neuroanatomy, neurochemistry, and evolutionary biology.
The notion of human superiority that runs from Aristotle’s hierarchy of existence through Descartes’s erroneous belief that animals were automatons should have been obliterated by Darwin and subsequent discoveries about evolution. But myths about who and what we are die hard. Humans have long resisted acknowledging that we are distant cousins to all other animal species, diverging from common ancestors millions of years ago. Yet recognizing that other species are special in no way detracts from the fact that humans are also special. The qualities that humans have relied upon historically in efforts to distinguish ourselves from other species—the “hallmarks of humanity”—include intelligence, emotions, language, tool use, memory, culture, foresight, co-operation, altruism, and self-awareness. Scientists are systematically demonstrating that we share these traits with other animals.
Scientists believe that the large brains of primates, cetaceans, and elephants evolved for dealing with social complexity—recognizing friends and foes, engaging in lifelong social relationships, co-operating for mutual benefit, and developing unique cultures. Humans were supposed to have the biggest brains, and thus the gold medal, in animal intelligence. Not so fast. The brains of Homo sapiens are outweighed by those of dolphins, elephants, and whales. In our defence, we cunningly deemed brain weight to be an unfair comparison, so we calculated brain-to-body-weight ratios. Then the tree shrew bests us, so that can’t be right. Despite being smaller than whale brains, human brains have more neurons (aha!), but whale brains have more glia, specialized cells used in information processing.
There is no question that dolphins, whales, primates, and elephants are highly intelligent. Dolphins not only have big brains, but possess extraordinary abilities such as sonar or echolocation, with which they send out sound waves that bounce back as echoes, providing extensive information about their surroundings. Echolocation enables dolphins to “see” through solid objects, like a superhero’s X-ray vision. For example, dolphins can tell if another dolphin, or a human, is pregnant, using their sonar to detect two separate heartbeats. A few years ago, scientists discovered that dolphin brains contain large numbers of specialized spindle neurons, previously thought to be unique to great apes. These neurons are believed to rapidly transmit important social/emotional information. In fact, dolphins’ brains have more spindle neurons than humans’. Dale Peterson writes in The Moral Lives of Animals that dolphins “have excellent memories and high levels of social and self-awareness, are excellent at mimicking the behavior of others and can respond to symbolic presentations, form complex and creatively adaptive social systems, and show a broad capacity for the cultural transmission of learned behaviours.” In short, dolphins are really smart.
The phrase “bird brain” has long been employed as a put-down, but may now be seen as a compliment. In 2004, scientists completely renamed the parts of avian brains based on new knowledge about their evolution. The brains of birds, contrary to previous understanding, are structurally similar to mammal brains. Despite having relatively small brains, crows, ravens, and jays—members of the corvid family—have proven to be talented problem solvers and tool users. In one experiment, a New Caledonian crow overcame a series of eight obstacles before acquiring a piece of aluminum and bending it with uncanny accuracy into a hook that it used to retrieve a morsel of food. The crow accomplished this feat on its first attempt.
Intelligence is not limited to primates, cetaceans, and birds. Archerfish can instantly calculate complicated mathematics of distance, speed, and time when blasting their prey with jets of water. They can learn to be better hunters by watching skilled individuals of their species. Many species, from monarch butterflies and humpback whales to Pacific salmon and Arctic terns, undertake amazing migrations every year without map, compass, or GPS.
A variety of different species practise deception, behaving in ways intentionally designed to mislead predators or even members of their own group. In his best-seller The Parrot’s Lament, Eugene Linden chronicles acts of deception by parrots, elephants, orangutans, dolphins, and hawks. Some birds feign injury to lead predators away from their nests. Jays will not cache food when other animals are watching, or will subsequently re-cache the food in a different location. Chimpanzees and gorillas will pretend not to notice desired food items when accompanied by more dominant members of their family. The less dominant primates will return later, unaccompanied, to collect the food. The zone-tailed hawk imitates the flying style of a vulture, a scavenger that poses no threat to other birds, then dives to attack unsuspecting birds. These uses of deception suggest that some species may have the ability to understand what other animals are thinking.
In her book How Animals Grieve, Barbara J. King defines grief as “when a survivor animal acts in ways that are visibly distressed or altered from the usual routine, in the aftermath of the death of a companion animal who had mattered to him or her.” Dolphins, primates, and elephants exhibit behaviour that clearly appears to be grief. According to Jeffrey Kluger, writing in Time magazine, “It’s well established that elephants appear to mourn their dead. They will linger over a family member’s body with what looks like sorrow, and African elephants have a burial ritual, covering dead relatives’ bodies with leaves and dirt. Elephants show great interest—some scientists suggest it may even be respect—when they come across the bones of dead elephants, examining them closely, with particular attention to the skull and tusks.” Similarly, great apes will remain close to a dead troop mate for days.
There are stories from Africa and Asia of elephant herds and tigers taking revenge on targeted human settlements or hunters for having slaughtered members of their families, stolen their food, or attempted to kill them. Baby elephants sometimes throw what can only be described as temper tantrums if their mothers deny them milk. In addition to observation, scientists can now use physiological data to track changes in the emotional state of animals. Recent studies have demonstrated that dogs feel elation in their owners’ presence.
In the 1970s, a captive killer whale named Orky at Marineland in Palos Verdes, California, ran his rostrum up and down the belly of his mate, Corky, four or five times, in much the same way a doctor might run ultrasound equipment over a pregnant woman’s abdomen. Immediately afterwards, Orky slammed his head against the wall of the tank over and over. This behaviour had never been seen before. Two hours later, Corky had a miscarriage. Since orcas have the ability to monitor pregnancies, Orky may have been expressing some kind of anguish or grief.
Humans may be the only species with a written language, but many animals have sophisticated means of communication that greatly exceed our understanding, including the use of sound and sonar. Primates have learned symbol and sign languages. Scientists studying wild chimpanzees have identified at least sixty-six distinct gestures, such as beckoning and waving. Kanzi, a bonobo “owned” by the Great Ape Trust and held at a research centre in Iowa, is famous because he knows some 400 words in sign language. When fed kale, he described it as slow lettuce, because it took longer to chew. When fed pizza, he signed cheese tomato bread. More significantly, he knows words that express emotions and abstract concepts such as happy, sad, be, and tomorrow.
Humpback whales sing songs that travel vast distances across the oceans. Thanks to the release of decades’ worth of records amassed by the U.S. Navy as part of its antisubmarine monitoring program in the Atlantic Ocean, scientists have an unprecedented understanding of this communication. In a press release, Dr. Chris Clark of Cornell University said, “We now have evidence that they are communicating with each other over thousands of miles of ocean. Singing is part of their social system and community.” New evidence proves that elephants can communicate with each other across huge distances by low frequency rumbling and by stomping on the ground, sending seismic signals that can travel more than thirty kilometres. These sounds are inaudible to humans but are picked up by special cells in elephant feet. Border collies can understand commands and hundreds of words for objects, and dogs generally understand non-verbal human communication such as pointing. Even bees communicate with each other, using a sophisticated code embedded in what entomologists describe as a dance. Bees perform this dance as part of collective deliberations about choosing a new hive site.
For a long time, humans were regarded as the only animals that used tools. Then Jane Goodall made her startling discoveries about chimpanzees that stripped leaves off small branches so they could extract termites from termite mounds. Scientists in the Ivory Coast’s Taï Forest observed adult chimpanzees showing young chimpanzees how to use rocks to smash open hard-shelled nuts. The researchers excavated the area and learned that this material culture had been passed down for at least 4,300 years by hundreds of generations of chimpanzees.
Ravens and crows use rocks to break open foods with hard exteriors, from nuts to shellfish. Sea otters balance shellfish on their chests while floating on their back, cracking them open with a rock clutched between their paws. Bottlenose dolphins off the coast of Australia place sea sponges on their rostrums like faceguards when rooting among sharp corals, discarding the sponges when fish dart out from the coral. Alligators and crocodiles have been observed balancing branches or sticks on their snouts and then partially submerging. Herons and other wading birds searching for nest-building materials are lured into the trap.
Orangutans have earned a reputation among zookeepers for their imaginative use of tools to facilitate escapes. The legendary Fu Manchu escaped repeatedly from an exhibit at the Omaha Zoo in Nebraska by using a piece of wire (which he kept hidden in his cheek) to pick locks. In 2016, new scientific studies reported discoveries about tool use by capuchin monkeys, bonobos, and even the California sheephead wrasse (a fish). The sheephead, like otters, uses rocks as anvils to break open and crush sea urchins before eating them. In 2017, bumblebees became the first invertebrate species to demonstrate their ability to use tools to achieve a desired outcome.
Closely related to intelligence is memory. Despite our prodigious smarts, we’ve all experienced the frustration of misplacing keys, wallets, and other important items. In that light, consider the memory power of the Clark’s nutcracker, a bird with a brain the size of a kidney bean. This small bird gathers seeds from pinyon pine trees in the fall, jams them into a pouch in its throat, flies as far as twenty kilometres to a higher elevation, and hides them in caches of one to fourteen seeds. In total, an individual bird will hide thousands of seeds. During winter and spring, the Clark’s nutcracker retrieves them, even when they’re buried by snow. Obviously these birds have an incredible spatial memory. Even more impressively, nutcrackers and jays eat cached foods in a particular order, based on anticipation of when the food is likely to spoil.
Then there is the chimpanzee. At Kyoto University’s Primate Research Institute, a chimp named Ayumu frequently embarrasses its human competition in short-term memory contests. The numbers one to nine are randomly scattered across a computer monitor with touchscreen technology. As soon as you touch the number one, the other numbers are blacked out but you must tap them in sequence. Ayumu can correctly memorize the location of the nine numbers almost instantly, while humans struggle to recall the correct sequence most of the time, even after prolonged efforts to memorize them. As researcher Tetsuro Matsuzawa told the Guardian, “No one imagined that chimpanzees—young chimpanzees at the age of five—would have a better performance in a memory task than humans.”
Like humans, many other animal species live in social groups that have recognizable and particular cultures. Culture can be defined as separate populations developing different ways of doing things through learning, rather than genetic inheritance. An essential element of culture is the transmission of knowledge to subsequent generations, such as chimpanzees training younger ones in tool use. Mounting recent scientific evidence proves that animals—from ants and bees to elephants and whales—live in complex social systems. Years of painstaking research by Professor Nigel Franks at the University of Bristol revealed that individual rock ants serve as teachers to other rock ants. Some species, including but not limited to primates, strategize politically, form alliances, and reconcile after disagreements.
Elephants possess substantial intellectual and cognitive abilities, demonstrate extensive emotional depth, and have complex social networks. Extended families of up to 100 animals live together, and elephants have been observed feeding those who are sick, injured, disabled, or otherwise unable to use their trunks. They use tools and work co-operatively to solve problems. Long-term studies of wild African elephants revealed the critical importance of elder matriarchs to herd survival because of their knowledge, experience, and wisdom. These older females know other elephants’ personalities, landscapes, migration routes, water holes, food sources, and strategies for avoiding or combating predators. Sadly, these are the individuals most targeted by poachers because of their long tusks. Who knows what cultural knowledge is being lost as these female elephants are killed?
Killer whales, like elephants, live in matrilineal family units for their entire lives. They travel together, hunt together, play together, and stay together. Dr. Hal Whitehead of Dalhousie University is a pioneer in the study of cetacean culture and has observed that “dolphins and whales live in these massive, multicultural, underwater societies.”
Humans once believed that we were the only animals with foresight. Yet creatures from blue jays to squirrels cache food for future consumption. If jays or ravens see other animals watching them hide food, they will wait until those animals leave, then move the food. A zoology student at the University of Cambridge—the aptly named Christopher Bird—found that the rook, a member of the crow family, could figure out that dropping stones into a pitcher partly filled with water would raise the level high enough to drink from it. The rooks even selected the largest stones first, recognizing that this would raise the level faster. Aesop wrote a fable called “The Crow and the Pitcher” about a bird that managed precisely the same feat about 2,500 years ago. It took a twenty-first-century scientist to show that the fable was factual.
Some animals co-operate to raise and protect their young, share food, groom each other, or take turns watching out for danger. Hyenas and killer whales both hunt in groups. There’s a video on YouTube of a group of orcas near Antarctica that locate a seal adrift on an ice floe. The killer whales circle the ice floe for a period of time, then all but one leave. Moments later they return, swimming side by side at high speed toward the seal before rapidly braking. Their actions propel a powerful wave of water that washes the hapless seal off the ice floe into the mouth of the orca that remained behind.
Scientists in Hawaii have repeatedly witnessed bottlenose dolphins playing a game where they lie on the head of a humpback whale. The whale slowly lifts its head, and the dolphin slips tail-first back into the water, like a child on a waterslide. In Australian waters, male dolphins co-operate to select and capture females for mating. Chimps co-operate in hunting and in conflicts with other groups of chimps. Experiments with elephants and birds have demonstrated that they will work together to secure food rewards. Biologists have observed many remarkable examples of cooperation between coyotes and American badgers in hunting ground squirrels together. Even fruit-fly brothers co-operate, rather than fight, in pursuit of a mate. Tommaso Pizzari, a zoologist at the University of Oxford, concluded that brother flies live longer as a result.
Self-awareness refers to the ability to recognize oneself as an individual distinct from the environment and other individuals. In 1838, Charles Darwin watched an orangutan at the London Zoo looking at herself in a mirror. He naturally wondered what she was thinking. More than a century later, scientists inspired by Darwin began placing animals in front of mirrors to explore the question of self-awareness. Animals are marked on their head or body (with paint or a sticker, for example) and then exposed to a mirror. If they touch the mark on themselves rather than on the mirror, scientists conclude that the animal perceives the reflected image as itself, rather than another animal. Experiments indicate that dolphins, orcas, Eurasian magpies, elephants, and some primates recognize themselves in mirrors.
Other scientists bristle at the notion that animals responding to seeing themselves in a mirror should be an indicator that they possess self-awareness. For example, in Beyond Words, conservationist Carl Safina argues that the day-to-day behaviour of many different species provides clear evidence of self-awareness. He concludes that “maybe a mirror is mainly a test for which species is the greatest narcissist.”
Altruism involves behaviour benefitting someone who is not a close relative, despite some personal cost or risk. Field researchers in Africa have observed chimpanzees assisting unrelated chimps without expecting favours in return. Lab tests done decades ago demonstrated that rhesus monkeys will consistently choose to go hungry if their decision to secure food would result in another unrelated rhesus monkey being subjected to an electrical shock. Dolphins have saved humans and seals from sharks and helped rescue whales stranded on rocks or beaches. In The Moral Lives of Animals, Dale Peterson recounts stories of a wild elephant in Kenya that defended an injured man from a herd of wild buffalo, a bonobo in an English zoo that saved a starling that had crashed into a window, and a gorilla at Chicago’s Brookfield Zoo that rescued a three-year old who fell into her exhibit, landing on a concrete floor.
In 2016, the journal Marine Mammal Research published a remarkable article about the seemingly altruistic behaviour of humpback whales. In dozens of recorded observations from around the world, humpbacks responded to the distress calls of other species—including seals, sea lions, and grey whales—that were being attacked by groups of killer whales. In each case, the humpback whales disrupted the hunt by harassing the orcas and driving them away. Scientists cannot find any plausible biological explanation for why the humpbacks would place themselves at risk on behalf of other species, and are left to speculate that this is an example of altruism.
These studies mark huge leaps in our scientific understanding of animal intelligence and consciousness in recent decades. From elephants and cetaceans to ants and fish, animals clearly feel, think, and reason. They are sentient creatures, not machines. As humans, we may never fully understand the intelligence, emotions, or morality of other species. We can study other types of animals, observe their behaviour, analyze their DNA, carry out sophisticated experiments, and attempt to imagine what goes on inside their minds, but knowing is probably an impossible task.
In 2012, a multi-disciplinary group of scientists who study how brains work produced the Cambridge Declaration on Consciousness, stating, “The weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Non-human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.” The declaration noted that many animals experience pain in ways similar to humans—the same chemical reactions in the brain and body (such as the production of adrenalin and other hormones) and the same observable physical reactions (like dilated pupils and elevated heart rates). Scientist Philip Low, one of the authors of the declaration, said that numerous colleagues approached him afterwards and said, “We were all thinking this, but were afraid to say it.” Reviewing the evidence, the New York Times concluded, “The overwhelming tendency of all this scientific work, of its results, has been toward more consciousness. More species having it, and species having more of it than assumed.”
From a scientific perspective, the myths of human superiority and exceptionalism have been repeatedly and convincingly debunked. As Charles Darwin observed almost 150 years ago, the difference between humans and other animals is one “of degree, not of kind.” After studying chimpanzees for more than forty years, in her foreword to Building an Ark: 101 Solutions to Animal Suffering, Jane Goodall concluded, “It is clear that there is no sharp line between us and chimpanzees, between us and the rest of the animal kingdom. The more we learn, the more blurry the line becomes. We are not the only beings on the planet with personalities and minds capable of rational thought and feelings.” The knowledge that animals feel, think, and reason has profound consequences for our relationship with them. As journalist Elizabeth Kolbert observed in the New York Review of Books, “To acknowledge that we are separated from other species by ‘degree, not kind’ is to call into question just about every aspect of modern life.” We have a powerful moral imperative to change the way we relate to, interact with, and exploit other animals.