Pat Shipman - The Animal Connection

Smoke and mirrors

Photo by Christal des Saint Marc

For some years now, I have explored the connection between animals and humans and its enormous impact on the evolution of our species. For example, many scholars believe that the invention of language was spurred by the adaptive value of collecting detailed information and sharing it with others in our group. The classic example is the elder who remembers from his or her childhood where there are deeper water holes and leads the group to them in times of drought.  

            The catch with tracing the origin of language is that words (much less syntax and grammar) don’t fossilize, so it is very hard to pin down exactly when this amazing ability first occurred.  Anatomists have struggled in vain to identify traces on skulls that would signal the onset of language.   

            In 1991, William Noble and Iain Davidson suggested a different, clever way to recognize the origin of language.

            “The property that most distinguishes language from other communication systems,” they wrote, “is that its signs are symbolic. All communicative systems are collections of gestures, whether vocal, manual, or physical; these gestures are signs and they convey meanings.” And they added, the relationship between the sign or gesture and the thing to which it refers is arbitrary — symbolic – and is recognized as arbitrary by those who use it.  Thus, whether you say dog or chien or Fido really doesn’t matter as long as the speaker and the listener agree on meaning.

            Basically, language has three key attributes. First, it is about something; there is a topic that is the subject of communication. Second, information about the topic is conveyed through symbols. Third, a vocabulary of symbols must be shared by the speaker and the intended audience if communication is to occur.

            Searching the fossil and archaeological record for the first evidence of symbols, Noble and Davidson identified the earliest symbols as being cave art – exquisite animal sculptures — 32,000 years old.  Since Noble and Davidson’s first wrote their seminal article, objects have been discovered that place symbolic behavior earlier than 100,000 years ago. For example, deliberately pierced shells that were apparently strung as necklaces or bracelets are now known from Israel and Algeria at about 135,000 years ago.  These objects of personal adornment are like tattoos, gang colors, school t-shirts, some hairdos, or badges: symbolic ways of proclaiming membership in a particular group. Decoding what that group was 135,000 years ago is almost impossible. 

         Similarly, Blombos Cave, a remarkable site in South Africa, has yielded nineteen pieces of ochre carved in geometric patterns from between 77,000 and 100,000 years ago.  What the patterns mean is as yet undeciphered (and may remain so); that the patterns had meaning is perfectly clear. The frustration lies in our ability to find such early symbols coupled with our inability to understand them.

            The earliest symbols we can decipher are only about 40,000 years old. They are figurative prehistoric artworks like the cave paintings and engravings from places like Chauvet Cave, the subject of the recent film “Cave of Forgotten Dreams”.

            These figurative images are overwhelmingly animals; the representations are intensely detailed and realistic, rich in information. I find it significant that these images do not depict landscapes, give directions for making tools or shelters or fires, or indicate where water or outcrops of useful rock can be found.  They very rarely depict people. To me, their content reveals that information about animals was more vitally important than these other topics and transmitting that information to others gave an immense advantage to those with language. This is an important part of what I have called the “animal connection” and demonstrates one way in which being connected to animals had a formative influence on human evolution.

            Now we can trace the influence of the animal connection on human evolution still further back in time than language, to visual perception. New findings by a team of neurobiologists provide strong support for the idea that the connection between humans and animals is very fundamental, very important, and very heritable.

            Florian Mormann from the California Institute of Technology and colleagues conducted a simple study on 41 epileptic patients who had intractable seizures. The subjects were undergoing electrophysiological monitoring to determine which parts of their brains were involved in seizures. Electrodes were implanted in three areas of the brain: the amygdala, the hippocampus, and the entorhinal cortex. All three regions are part of the limbic system which processes and integrates events of emotional importance into long-term memory.  The limbic system focuses attention on important aspects of the environment, prepares parts of the body for action when appropriate, and motivates bodily expression of important information. 

            During each experimental session, subjects viewed approximately 100 assorted images on a screen while the responses of neurons in these three areas was recorded.  The images were projected randomly and showed people’s faces, animals, landmarks, or objects. The people were often celebrities whose faces would be known to subjects. Animals shown included mammals, birds, insects, and reptiles, but none of the animals were personally known to the subjects. Some were domesticated animals and others were wild. Landmarks included famous sites – like the Egyptian pyramids or the Colosseum in Rome – and unknown scenes.  Objects included cars, tools, and food items. The readout from the implanted electrodes indicated which regions of the brain responded to which particular stimuli.

            The amygdala showed a strikingly different response pattern from the other parts of the brain.  Neurons in the right amygdala responded preferentially to pictures of animals and responded more markedly to such images. The left amygdala, hippocampus, and entorhinal complex showed no such preferences. The differences were very significant statistically.

            After checking for and eliminating many potential confounding factors, Mormann and colleagues concluded, “[The right] amygdala is specialized for processing visual information about animals.”  They explain that this function is localized to the right side because the entire right hemisphere of the brain has is specialized for responding to unexpected and biologically important stimuli.

            Why would the right amygdala be hard-wired for responding to, focusing on, and remembering visual information about animals?

            My answer is that this functional specialization in the brain helped our early ancestors survive their anomalous position as predators-without-bodily-equipment long before the invention of language. Unlike other mammalian predators, our ancestors did not evolve strong forelimbs, grasping claws, slicing teeth, speed, or an enhanced sense of smell for capturing animals. Our ancestors took an evolutionary short-cut 2.6 million years ago and invented stone tools.  With those tools, they were able to obtain meat, fat, marrow, and hide from prey that they had never been able to take before. Abundant cutmarks on fossil bones starting at 2.6 million years ago show that our ancestors quickly became highly effective hunters, even though they had none of the bodily equipment of true carnivores.

            By being predators-without-equipment, our ancestors came under evolutionary pressure to pay close attention both to the real carnivores, who competed for prey and wouldn’t balk at eating our ancestors, and their own potential prey. Accumulating visual information about the behavior of both sorts of animals became key to survival.

            The work by Mormann and his colleagues provides the electrophysiological information that explains the results of another, early study, which focused on behavior. In a set of experiments involving the ability to detect visual changes, Joshua New, Leda Cosmides, and John Tooby exposed subjects to a pair of rapidly changing, complex images of natural scenes with a single alteration (a format known as a change detection study). They measured how quickly people were able to spot the change according to the category of the item that changed. Subjects detected changes in animals and other humans faster and more reliably than in stationary objects (tools, plants) or inanimate objects that are capable of movement (vehicles).

            New and colleagues argued that observing changes in vehicle positions is a more pertinent survival skill among the subjects they tested than observing animals, since the subjects lived in urban environments. Yet, despite a lifetime of learning to watch out for moving cars, the subjects were more sensitive to changes in the position of humans or animals than vehicles.

            This team concluded that the visual monitoring system is equipped with “ancestrally-derived selection criteria” – a special sensitivity to animals and people – that “appears well designed for solving an ancient adaptive problem: detecting the presence of human and non-human animals and monitoring them for changes in their state and location.” In short, they suggested that the sensitivity to visual information about the position of people and animals was an ancient one based on ancient needs of our species.

            Both behaviorally (the change detection study) and electrophysiologically (the recent study), there is very strong evidence that a specific part of the brain is unusually sensitive to visual information about animals.  We are hard-wired to pay attention to animals. This enhanced the survival of our lineage so significantly that a part of the brain was actually specialized to collect and respond to animal information.

            Did you inherit a love of cats from your mother?  Maybe, maybe not.  But consciously or unconsciously, you did inherit from your ancestral mother a special ability to gather information about the animals around you.

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Readers can find more detailed explanations of my theory and the studies in the references below. 

Mormann, Florian, Dubois, Julien, Kornblith, Simon, Milosavljevic, Milica, Cerf, Moran, Ison, Matias, Tsuchiya, Naotsugu, Kraskov, Alexander, Quian Quiroga, Rodrigo, Adolphs, Ralph, Fried, Itzhak,  & Koch, Christof. 2011 “A category-specific response to animals in the right human amygdala”. Nature Neuroscience 28 August 2011.  doi:10.1038/nn.2899.

New, Joshua, Cosmides, Leda, and Tooby, John. 2007. “Category-specific attention for animals reflects ancestral priorities, not expertise.” Proceedings of the National Academy of Science USA 104 (42): 16598-16603.

Shipman, Pat. 2011. THE ANIMAL CONNECTION, W.W. Norton & Co.

___________ 2011 “How Animals Shaped Our Minds.” New Scientist 210: 32-37. ___________ 2010. The Animal Connection and Human Evolution. Current Anthropology 51(4): 519-32.

Here’s a link to a radio interview about the animal connection that I did recently.

I am not one of those people who knew from age 12 what she wanted to be. In college, I had two inspiring professors of anthropology and their classes started a lifelong fascination. When I graduated from college, I took a job at a publisher in NYC where I had had a summer internship.
I married shortly after graduating, and my husband and I left on our honeymoon using a passport I had obtained as a single woman, in my maiden name (Shipman). We married in 1970, during the rise of the feminist movement, and the question whether or not to take my husband’s name was a serious choice. I decided to be traditional and took his name.
That meant I had to take my passport in for amendment after the honeymoon. On the crucial page – the one with name, birth date, and photo —- the Passport Office took a large red stamp and marked VOID VOID VOID all over it. Then someone added a handwritten note: “See page 8.” On page 8 was a notation that my name had been changed on a particular date.
I thought I’d get used to his name, but I didn’t. I jumped every time people referred to me as Mrs. So-and-so, because that was my husband’s mother: a nice lady, but not me. I mis-signed documents and letters repeatedly because I was unused to my new name, which meant I had to type them over (no computers then and I certainly didn’t have a secretary to do my typing). I hesitated to identify myself on the phone. For a while, I tried using Shipman as a middle name & my husband’s name as a surname, but that got pretty cumbersome. I felt like an imposter.
My husband went to a demanding professional school, working long hours and weekends, while I brought in the meager bacon. After a while, I quit my job and started graduate school in anthropology, with the financial assistance of my parents and later a fellowship. Three years after marrying, my first husband and I divorced.
The brightest ray of light was that I got my own name back. I was Pat Shipman again.
I loved graduate school and did well. I was becoming me, not an extension of someone else, and my future would be determined by me. That me was working hard to become an anthropologist and to get over the sadness and loss of the divorce.
I completed my coursework and researched my M.A. in Ethiopia, a glorious and strange African country. I passed my comprehensive exams well. (Comps are the much-dreaded “hoop” that graduate students in many programs must jump through in order to be admitted to candidacy for the Ph.D. They measure if the student knows the fundamental facts, theories, and arguments of the field.)
Proud of the changes in my life, I took my passport back in to the Passport Office and had it amended again to reflect the divorce. When I got it back, I took a look. On the opening page, it still said “VOID VOID VOID see page 8” but on page 8, there were new notations. The same stamp appeared – VOID VOID VOID – and a small handwritten notation, “See page 10.” On page 10 was an office note that my surname had been changed again to Shipman, on such-and-such a date. I breathed a sigh of relief but I didn’t think about the larger implications much.
I should have. I had learned in anthropology courses how very important names are. Specific customs vary widely, but many groups believe that if you know someone’s name, you have power over them. So, for example, Navajo do not refer to other family members by their personal names but by their position in the family, using “son” or “mother” instead of the name. If you act in someone’s name, you are borrowing their authority or power: “In the name of the King, I hereby…” In much medieval folklore – and the Harry Potter books — the devil and magical creatures can be summoned up by those who know their name. Among many ethnic groups, a child is not given his or her real name until well after birth to protect the newborn child from curses. And commonly, new names are given to mark entry into a new phase of life.
On my next trip to Africa, I was going to be a volunteer on a dig in western Kenya. I needed to find a thesis topic and my adviser had begged, pleaded, & arm-twisted in order to get me a place on that dig, which was being run by a colleague with whom he had been at grad school. My adviser promised that I would pay my own way, do whatever I was told, not make trouble, and get on the first bus back to Nairobi if I was in any way a bother. He also said, I found out later, that I was very bright but that I “came on a bit strong,” which has been a joke phrase in my family ever since.
Going into Kenya, exhausted by the two days of travel but exhilarated by being back in Africa, I hit an unexpected snag. I already knew that officials in Third World countries can be difficult; some of them simply enjoy demonstrating their power over foreign tourists. Others resent their low pay and difficult lives compared to the apparently rich visitors they see every day. And many are embedded in a rigid bureaucracy, which makes them very uneasy with anything that is not usual, that might require an independent decision for which they might later be criticized.
I approached the Passport Control officer, smiled and greeted him, and handed over my passport. Then I waited. And waited. He opened the passport, reading every item on the opening page and looking with alarm at the VOID VOID VOID stamps. (Oh no, I thought.) Then he turned, very slowly, to page 8, and read page 8 very carefully and slowly, several times. Then he went back to page 1 and reexamined it. Then he went back to page 8 and read it again. Finally, he went to page 10 and read it. I was sweating from anxiety but I strove to appear calm, pleasant, and unthreatening.
The officer returned again to page 1, comparing it with page 10.
He looked up at me and said, “I see. Back to square 1.” He smiled, then paused and cocked his head. “But why?”
“My father has no sons,” I said.
“Ah!” The official exclaimed, beaming as he wielded his rubber stamp on the three vital pages of my passport and his ink pad — squish, thump, squish, thump, squish, thump. He handed the passport back to me.
As I walked away, I thought about what had just happened. I had given the official an answer he could understand and appreciate. When I said, “My father has no sons,” I was speaking a profoundly important truth in Kenyan culture and in mine Maybe honoring my father was why I felt the need to hang on to my own name.
I had become an anthropologist.

The Financial Times

http://www.ft.com/cms/s/2/47e19728-cd99-11e0-bb4f-00144feabdc0.html#ixzz1WWIOOiHS

August 26, 2011 9:57 pm
Wild at heart
By Stephen Cave
We see ourselves as standing above the rest of creation, but could animals be shaping us just as we are shaping them?

Oh victorious cow! In its bid for world domination this cunning ungulate has succeeded in training a great army of apes to do its bidding. These slavish primates, so reliant on the gifts of the udder, first killed off the cows’ predators, such as wolves and bears, and even exterminated those other large herbivores, mastodons and mammoths, that once offered competition for the best grasslands. Now the apes are clearing the world’s ancient forests and turning them over to pasture where their bovine masters might graze. They act as if mesmerised by those big wet eyes.
In return for these services a certain sacrifice is made: some cows must be willing to die for the good of their kin. This is the price of power over the primates, who have become addicted to the meat and milk the cows provide. Thanks to this blood pact, the world cattle population has risen to well over a billion, and their dominion is rapidly spreading. But for those pesky vegetarians, their victory would be secure.
So might the relationship between humans and cows look were it not for our tendency to put ourselves at the centre of every story. Where biologists come across relationships like the one between us and our cattle elsewhere in nature, they describe them as “mutualist”, meaning that through their mutual interaction both species benefit. So we provide protection and pasture for cows in return for milk and meat, just as some species of ants provide protection and pasture for aphids in return for the sweet liquid they secrete.
Much as we like to see ourselves as standing above the rest of creation, an increasing amount of research is demonstrating that it is just such interactions that have made us what we are. To understand both our past and our present we must look to these other species – not just cows but also lions, worms, mushrooms and even microbes. As all four of the books under review contend, we need nature in order to be fully human.
This thesis is plausible – indeed important. We are not and never have been set apart from the web of life around us: “No species is an island,” as the biologist Rob Dunn puts it in The Wild Life of Our Bodies: Predators, Parasites, and Partners That Shape Our Evolution. Even in our modern high-tech urban environments we remain entirely dependent upon these other organisms. “If cows went extinct tomorrow,” writes Dunn, “millions of humans would die.” Our dependence on a few varieties of the grass plant (wheat, rice and maize) is even more striking: if these disappeared, the great majority of humans would quickly starve.
For most of our evolutionary past, however, such relationships were both more varied and more immediate. Our bodies and brains have been fine-tuned over millennia to respond to thousands of species of trees, roots, birds, predators and bugs. The savannah, not the shopping mall, is our natural habitat. The central role of these other creatures in our evolutionary history is the subject of Pat Shipman’s The Animal Connection: A New Perspective on What Makes Us Human. An anthropologist specialising in our early ancestors, she begins with the simple observation that wherever in the world one finds people, there are always animals being milked, walked, herded or watched.
Take dogs, for example, of which there are now hundreds of millions worldwide, keeping us company everywhere from New York apartments to the plateau of Tibet. Shipman believes they were domesticated from wolves more than 30,000 years ago as they “helped hunters find or track prey and protected their home territory and their social group (which included humans)”. It is well understood how we have shaped these wolves: our ancestors would have favoured those that were friendly and useful to humans, so eventually creating the domestic dog of today. But less well studied is how this relationship changed us. Shipman argues that those humans who showed the right skills and sensitivity to manage wolves outlived and out-bred those who tried to go it alone; the result is a world of dog-lovers. Domestication runs two ways.
Much as we like to see ourselves as standing above the rest of creation, an increasing amount of research is demonstrating that it is just such interactions that have made us what we are. To understand both our past and our present we must look to these other species – not just cows but also lions, worms, mushrooms and even microbes. As all four of the books under review contend, we need nature in order to be fully human.
This thesis is plausible – indeed important. This is a bold hypothesis, and among the evidence she presents is also a great deal of speculation. But there are at least some cases where the results of these connections are clear – such as our alliance with the cow. DNA profiles suggest that 10,000 years ago, the vast majority of humans were lactose intolerant – genetically incapable of digesting milk beyond infancy. Yet in Europe and those areas colonised by Europeans, 95 per cent of the population now can (and do) happily consume dairy products into their dotage. So in these cow-rearing lands, humans with the ability to digest milk spread at the expense of their fussier cousins. In effect, just as we have bred cows for high milk yield, so they have “bred” us to digest this milk (and therefore to have a reason to care for them). And if we have evolved lactose tolerance through our interaction with the bovine, it is not crazy to think we might also have evolved a fondness for dogs, or a predilection for observing the behaviour of predators.
Even if the role of animals is only a fraction of the story, it offers an important and oft-neglected perspective on human development. In The Wild Life of Our Bodies, Rob Dunn extends that perspective beyond the farmyard to a host of other critters. It is not only our familiar furry friends whose company we have evolved to need, he argues, but even parasitic worms and bacteria. In this respect, our success in eliminating such organisms over the past century is not the unalloyed blessing it might seem. Our bodies have had no time to catch up with this unprecedented isolation – 100 years of hygiene is nothing compared with our aeons evolving in the wild. As a consequence, believes Dunn, we are malfunctioning.
As evidence he points to the diseases of modernity: “diabetes; autism; allergies; many anxiety disorders; autoimmune diseases; preeclampsia; tooth, jaw, and vision problems; and even heart disease”. The anxiety disorders he puts down to the removal of the original objects of our angst: big scary predators. Many of the other problems he believes are the result of an immune system which is out of kilter as it has evolved to live with a menagerie of now absent invaders.
Some people are, therefore, taking the matter into their own hands. One American asthma sufferer, for example, read that parasitic worms prevented the overreactions of the immune system that might be behind his condition. So he took a flight to Cameroon and wandered the latrines barefoot until he felt “the itch of worms crawling through his thin, once-affluent skin”. Apparently cured of asthma, he now runs a worm-therapy clinic in Mexico.
Though such stories are striking, some of Dunn’s prose is as wild as the subject matter – as if he thought he must compensate for the dryness of much scientific text with hyperbole and histrionics. He need not have – when the subject matter is allowed to speak for itself, it is fascinating. His conclusion, though, goes beyond the science to speculate on how we might re-wild our lives. First, we have to be a little less squeamish about the bugs and worms with which we have long shared our homes and even bodies. Second, we need to bring wild spaces into our towns and cities, with rooftop gardens, high-rise farms, greenery in every spare space and even the re¬introduction of large predators such as wolves and bears.
It is for just such projects as these that Richard Louv, author of The Nature Principle: Human Restoration and the End of Nature-Deficit Disorder has long been campaigning. His previous book, Last Child in the Woods (2005), struck a chord with many people when he argued that our children are suffering from what he calls “nature-deficit disorder”. The Nature Principle extends the idea to grown-ups and tells us what to do about it.
Louv draws on research showing that even small-scale exposure to nature – a view of trees, a walk in the park – can make a difference to our physical and psychological well-being. He believes this insight is now catching on, and that soon doctors “will prescribe green exercise and other nature experiences”, while “developers and urban planners will create homes, neighbourhoods, suburbs and cities that are nature-inclusive”. In the meantime, we can all do our bit by planting a butterfly-friendly shrub or organising local walking groups.
Unlike Shipman’s and Dunn’s books, The Nature Principle does not pursue a grand theory. Rather it resembles a naturalist’s field book: a collection of anecdotes, evidence and personal stories that Louv has collected in his years of writing and campaigning. For a book about nature, it suffers from serious overcrowding, as endless characters come and go. But the cumulative effect is inspiring: Louv’s is not a counsel of despair but a gentle exhortation to get out and make the world a little bit greener.
This is simple but sensible advice now that we spend ever more time in front of screens. Yet perhaps even our technology can help bring us some of the benefits of nature. This is something the psychologist Peter Kahn has long been exploring in his research, clearly and passionately documented in Technological Nature: Adaptation and the Future of Human Life. He has, for example, measured the benefits of a window overlooking trees versus the same scene shown on a large plasma screen; the way people interact with a real dog compared with their responses to a robot dog; and even the effects of gardening by computer-steered remote control.
Like the other authors mentioned, Kahn is convinced by the evidence showing that experiencing nature is good for us. What he wanted to know is whether that goodness can be reproduced, given that we are now surrounded by computer screens, smartphones and other artefacts of the silicon age. His results are unequivocal: digital nature is better than nothing but not as good as the real thing. He therefore concludes that “if we employed technological nature only as a bonus on top of our interactions with actual nature, then we would be in good shape. Unfortunately, we keep degrading and destroying actual nature, and we are becoming increasingly impoverished for it.”
If Shipman and Dunn are right in proclaiming the importance of other species in every step of our evolution, then we should not be surprised that those of us surrounded by concrete and glass suffer from Louv’s nature-deficit disorder, nor, as Kahn concludes, that the digital version is a poor substitute. Although they represent quite different disciplines, they come to the same conclusion: that our bodies are crying out for the wild. So put some boots on and go outside. The cows are waiting.
Stephen Cave is a writer and philosopher based in Berlin. His book, ‘Immortality’, is published next year by Random House
The Animal Connection: A New Perspective on What Makes Us Human, by Pat Shipman, Norton, RRP£17.99, 336 pages
The Wild Life of Our Bodies: Predators, Parasites, and Partners That Shape Our Evolution, by Rob Dunn, HarperCollins, RRP£16.99, 304 pages
The Nature Principle: Human Restoration and the End of Nature-Deficit Disorder, by Richard Louv, Algonquin Books, RRP$24.95, 320 pages
Technological Nature: Adaptation and the Future of Human Life, by Peter H Kahn, MIT Press, RRP£17.95, 240 pages