From Predators and Farmers to Farmers of Predators

I remember it was late at night and my wife was downstairs talking animatedly on the phone in Oromo. I figured she must be talking to family in Ethiopia. After she hung up, she came upstairs and explained to me that one of her brothers had been jailed. He’s a glass-half-full sort of guy so he wasn’t too upset about his situation and in fact he was pretty happy with the food and getting a free bottle of water each day. But what irked him was the reason he was jailed. He was on a bus from Addis Ababa, heading home to the family farm for a visit when security forces stopped the bus. They ordered everyone off and jailed all of the men on suspicion of being in transit to join one of the protests that were springing up across the country. It spoke of a paranoid government and lot of tension in the Oromo region. Protests were springing up like spot fires, and among the farming communities everyone was expected to participate. As I mentioned in my previous posts I was intending to re-visit Ethiopia and spend a year doing research on animal domestication – how the presence of hyenas influenced the choices of livestock animals. But the security situation had me postponing my visit month after month. By June 2016, an estimated 400 protesters had been killed by security forces and many more injured. Westerners in Addis Ababa were being advised not to venture outside of the capital. There was no way I would take myself, let alone my family into that war zone.

I needed to save my research project but with limited data from my fieldwork in Australia and next to no hope of going back to Ethiopia my original idea had hit a brick wall. I’d accepted that it was beginning to look pretty dead in the water but what of an alternative? Romania was an option. That country has an abundance of bears and wolves as well as a lot of small-scale livestock herding. I could see how those predators were influencing relations between herders and herded. But with only 18 months of my contract remaining it would be a tall order to plan and execute some meaningful fieldwork in a country to which I’d never been. At around this time my old pal, coincidence, decided to step in and guide me. A neighbour who knew that I was doing dingo research suggested I talk to a friend of hers. This friend had three dingoes who she kept as pets. At the same time I met someone who works for the forestry department and he told me about a seminar that he was organising featuring a man who kept native Australian bees. And it occurred to me that domestication might be something that was happening in real time in my own back yard. My mind started racing. I knew that crocodiles were being farmed in northern Australia and I’d seen emus on a farm just a few kilometres from my home. I knew also that barramundi and other fish species were being farmed in Australia because it said so on the supermarket labeling. I wondered if kangaroos were being farmed as well. And there before me was the next phase of my research: I would investigate the process of domestication as it unfolded with native species in Australia. It all made so much sense. Rather than applying an Ethiopian model to try and reconstruct domestication during the Neolithic, I would instead study domestication as a contemporary process. I’d see what sorts of human capacities farmers brought to the process and how domestication feeds back into society. I felt good about it. I’d be doing research in my home country, speaking my native tongue and without the presumptuous, world-is-my-oyster attitude that saw me go to Ethiopia to do hyena research 5 years previous. Whereas I felt like Ethiopia was a place that I’d exploited for research purposes, I didn’t have the same misgivings about Australia. And flushing toilets – how good are they! So I ran the idea past the principals of the research project, Agustín Fuentes and Celia Deane-Drummond. At the time we were at a conference in Durham. We took a break and got together in the corner of a pub where I laid out my idea. Celia was disappointed that I wouldn’t be revisiting Ethiopia but trusted my judgement. Agustín, as always, was enthusiastic about the new direction of the research. So I made the requisite adjustments to my ethics guidelines, checked up on what permissions I’d be needing, and before long I was on the road north to visit unconventional farms and homes where native Australian animals were being enfolded into the social and economic worlds of humans. I was about to bear witness to the new wave of domestication.   

Thinking cattle

While I was in the middle of my field research on anti-predator behaviours in Australian cattle I was also doing surveys and interviews. With the help of Local Land Services in Grafton, NSW, I sent out about 150 surveys to farmers who had registered to use poison baits to control dingoes. The surveys were a little unusual compared to the usual wildlife-conflict, farmer surveys which ask things like ‘How many animals have you lost?’ and ‘What is the total value of livestock losses for the past year?’ After eliciting some general demographic and geographic information, the questions set about uncovering what farmers thought about what animals were thinking. I’d been reading a lot about Theory of Mind – the ability that most humans have to imagine what others are thinking – and I wondered how it played into farmers’ relations with livestock and predators. During my time in Ethiopia I found that people constantly deployed theory of mind in terms of the way they imagined the worlds of other animals. Not only did they construct ideas about what predators such as hyenas were thinking but they did likewise with the livestock animals with whom they shared their houses. This stood as a marked contrast to the predominant Western view of animals as mindless grass munchers or implacable predators. Considering that rural people in Ethiopia share their lives intimately with other animals, I wondered whether the western view was a consequence of living at a distance from animals. After all, most farmers in Australia do not share their houses with their livestock and certainly don’t know every animal by name, as do Ethiopian farmers. But then maybe the Western view of animals was widespread only in academic circles. Maybe Australian farmers saw the world differently. So the surveys I sent out included questions aimed at testing this. Such questions as ‘Do your animals know when dingoes are present?’ tested whether farmers ascribed thoughts to their livestock animals. The surveys also included an option to have a face-to-face, follow-up interview and over a dozen farmers took me up on that. So I made some trips around the New South Wales tablelands to do interviews with farmers where I asked some pretty odd-ball questions about what they thought that cows, sheep, and dingoes were thinking. What I found was surprising. The Australian farmers I spoke to were little different to Ethiopian farmers in thinking and talking about what animals were thinking. Even a cattle farmer from the New England Tablelands with hundreds of acres, and thousands of animals – who had a farm manager to do the hands-on work with the animals, talked about the mental lives of his cattle.

I ended up writing a book chapter about this. After discussing the ways in which Oromo farmers deployed theory of mind as a practical means to control their livestock animals I suggested that, because of fencing as a means of control in animals, Australian farmers didn’t really need to. But my findings that Australian farmers did deploy theory of mind suggest that humans can’t help but ascribe mindedness to other animals. In fact humans compulsively ascribe mental states to all manner of things, from cars to weather phenomena. And this is borne out by the results of experiments in which subjects are asked to describe sequences of animated shapes. What these experiments show is that with the exception of some people on the autism spectrum, humans readily attribute mental states to animated objects even if those objects are basic shapes such as triangles and circles. But while theory of mind may have contributed to the initial processes of domestication, I argue that it wasn’t crucial. Proof of this comes from individuals with autism who struggle to deploy theory of mind but are very adept at understanding and managing livestock animals. Temple Grandin being a case in point.

Meanwhile the data came in from the camera traps. It wasn’t promising. There were thousands of images of cattle, a handful of birds, a cat, a wallaby and only three images of a wild canid. Worse still was that one of the dates on which the canid was photographed happened to be one where I wasn’t on-site collecting data on livestock. So my spatial analysis fell apart due to lack of data on predator movements. But I consoled myself with the results from my surveys and interviews. I figured these would give me something on which to base comparisons when I got to Ethiopia. It was around this time that an Ethiopian shit-storm blew up on the horizon.

Staring at Cows

In my last post I talked about how I arrived at a theoretical model for how animals became domesticated during the Neolithic. What was unique about this model was that it allowed space for the agency of livestock animals in early domestication. Based on what I saw in West Shawa, Ethiopia, I theorised that early animal domestication involved goats and sheep deliberately hanging around human encampments because these afforded protection from predators. No fencing needed. At the same time, the animals would be unaware that humans were predators themselves.  In West Shawa, people are careful to slaughter animals out of sight of the others. The animals have no idea where their herd mates disappear to and all they see in the evening is humans with plates full of unidentifiable meat. So for a livestock animal of the Neolithic, human encampments may have seemed like a pretty good deal. The absence of predators would have been pretty obvious and the quantities of grains and vegetables would have been irresistible. Ignorance is bliss.

Still, the model I proposed didn’t explain dog domestication – that model would come later (Spoiler alert: kidnapping wolf pups!) – but it did go some way towards integrating predators and the agency of livestock animals into the process by which humans came to live with sheep, goats and cows. The question then became: What in the contemporary world could I look at that would inform that model? The obvious answer was the relationships that I’d encountered between people, livestock, and hyenas in Ethiopia. There, the cows, sheep, goats and others have a lot of freedom in terms of feeding and movements and yet something keeps them coming back to their human masters and mistresses, day after day. On the one hand that something could be supplemental food. On the other in could be protection, or shelter from rain, or the smell of roasting coffee. Or it could be a combination of those. So I set about planning a research project that would go some way towards answering that question.

I would spend a year doing fieldwork, literally in a field, monitoring the movements of livestock animals and making observations of the variables that might have some correlation with those movements. Whether they were being fed, whether they were being coerced, if they were doing things out of habit from infancy. I’d also collect data on the presence of hyenas and see if there was a correlation between hyena presence and livestock associations with humans. I sought out two places where it would be ideal to do the research. One was where my in-laws lived and farmed and the other was southwest of there, where farmers lived in close proximity to a national park where presumably hyenas were more abundant. Out of all this I figured I’d have a pretty good idea of why it was that livestock animals were voluntarily lining up at the doors of human households to be let in for the night. And from this I could speculate with a little more authority on the early days of animal domestication. As usual, the universe had other ideas.

While I was still in the planning stages, news started coming through of protests in Ethiopia’s capital, Addis Ababa. According to the news, land was being taken from farmers on the outskirts of Addis and handed over to property developers. To add fuel to the fire the farmers were of the majority Oromo ethnic group and these people already had a problem with Ethiopia’s minority-led ruling party. There were large scale protests in the capital and security forces responded violently. The protests spread and before long much of the Oromia region was in a state of unrest. What’s more is that the district in which I was planning to do my fieldwork is traditionally the centre of Oromo resistance to the government. There was a protest at the local university and students were killed by police. In short it wasn’t safe to go there at that time. Yet I didn’t want to let go of my research idea.

It was also around this time that I met Paul Meek from the Department of Primary Industries where I live in northern New South Wales. He was involved with monitoring dingoes with camera traps specifically to aid Australian farmers in their efforts to control predators. It was he who gave me the idea of doing a comparative study in Australia. While I was waiting for the situation in Ethiopia to stabilise, I could make observations on a cattle farm, mapping the movements of livestock in relation to farmers and dingoes. I could see if a fenced environment with little interaction between farmers and cattle would affect the ways in which the livestock animals responded to the presence of predators and in the long term compare these with data from Ethiopia. So after securing the relevant permissions, I found a willing farmer, and with the help of Paul, set up a series of camera traps around the farm. He wasn’t confident that we’d get solid results because there had been some widespread dingo poisoning carried out in the area but the farmer claimed he’d seen dingoes boldly crossing the property recently, and this gave me hope. So while the camera traps did their passive monitoring I drove to the farm each morning at sunrise and using GIS software, plotted the positions of the livestock animals every thirty minutes. The cattle tended to get edgy when I went around on foot so I instead drove around the farm and made observations which I plotted directly on a laptop, while I listened to the car radio. Compared to my time 5 years previous, trudging after hyenas in drainage lanes lined with garbage and excrement, it was pretty cushy fieldwork. Though it was pretty mind-numbing staring at cows. I wasn’t familiar with the individual cows so I couldn’t pick up any nuance in their relationships. Who hung out with whom; who decided when to move on; who was given access to the best grass. My main takeaway was that cows do in fact eat grass.

From the data I’d collected I was beginning to see some patterns though. The stand out was the positioning of the calves: always towards the centre of the herd. But until I could see the data from the camera traps I wouldn’t know if these positionings were a response to the presence of predators or just stuff that cows did. And I hadn’t seen a single dingo during my time making observations. I would have to wait until the data came in from the camera traps.

Herding livestock in Ethiopia. Photo courtesy of Wendy Tanner

The Evolution of Ideas: Hyenas to hyenas

I haven’t cross-posted like this before but I want to get this out to a broad audience and my hyenas blog has a larger following. Besides, the subject matter is somewhat hyena related because it was my hyena research that kicked it off in the first place.
Over the next few posts, I want to talk about my new (and reasonably priced) book Crocodile Undone, due out in May of this year. I’m not going to preview the content of the book here, although there will be a lot of clues as to what it’s about. Rather, I’m going to write about how the book came to be. After Among the Bone Eaters was published, the question I was most often asked was ‘How did you arrive at that subject?’ In terms of this latest book this is a worthwhile question because answering it lets me reflect on the flow of events, coincidences, and choices, the outcome of which is 240 pages of non-fiction, three beehives in my back yard, and back pain for the remainder of my life.
Crocodile Undone is the product of a research project that I undertook under the guidance of Agustín Fuentes at the University of Notre Dame. From the outset, and to his credit, Agustín gave me almost free-reign in terms of what I could study. His only condition was that it be something to do with domestication, broadly construed. Looking back on my previous research I could easily see how Harar’s hyenas might have something to say about domestication, or in narrower terms, the original domestication of dogs during the Palaeolithic some 15,000 years ago. This is because on face value the situation in Harar has parallels to one of the scenarios that has been proposed for how dogs became domesticated. This scenario depicts pre-domestic dogs (or wolves) as camp followers; as hangers on who found that the closer they got to human camps, the better the chances that had of getting some food scraps. It suggests a selection for tamer individuals and not long thereafter, dogs making themselves at home within human communities.
In Harar, the hyenas are indeed dependent on the human population for food, and the less fearful, less aggressive hyenas probably have a much better chance of getting food than their wilder clan mates. But it’s not so much the similarities that have a bearing on our understanding of dog domestication as it is the differences. The city of Harar produces an awful lot of food scraps for not very many hyenas and it’s a pretty safe bet that a band of human hunter/gatherers in Palaeolithic Eurasia did not produce any where nearly as much edible food waste – if any. What’s more hyenas and wolves are distinctly different creatures with different evolutionary histories. Hyenas evolved alongside humans over millions of years while wolves first encountered humans in the Pleistocene. And there’s not as much archaeological evidence of wolf/human competition as there is hyena/human competition. So the individuals of each species bring a very different package to a relationship with humans and disentangling these differences would be a very difficult task. In fact it was this potential quagmire of false equivalences that swayed me. While I’d hoped I could revisit my beloved Harar hyenas for a second research project, I realised that I would have to look elsewhere for some meaningful subject matter to enlighten us about domestication processes of the past. In the next post I’ll talk about where that realisation led me.

Economy of Scales

Rock Steady patiently waiting for his lunch (and thinking that I might be it). Note the state of the wire fence from Rock Steady pulling on the mesh

Just north of Rockhampton at the end of a dirt road and across a causeway onto an island of sorts is an unusual sort of farm. This is Koorana Crocodile Farm, the first of its kind to be established in Queensland and probably the most well-known, not least because of a reality TV series called croc college.  The farm is the result of a lifetime’s work and passion of John Lever who previously worked on conservation, management and farming crocs in Papua new Guinea. John established Koorana out of a passion for crocodiles and strategic conservation, which is essentially giving people a reason to conserve something by making it valuable in some way.

Crocs are made valuable because people like to wear their skins on their feet and  hanging by a strap over their shoulders. The skins fetch a hefty price in the fashion industry and more so if they have a brand name stuck on somewhere. There’s also crocodile meat and the fascination of crocs to tourists but the skins are what makes it viable to establish a crocodile farm. They grow and mature far too slowly to be profitable in terms of meat production.

This slow growth rate and maturation are things that make crocodile farming a challenge but also things that make me wonder about the kinds of selection that are happening. In speaking with John, I bring up the subject and right away he understands what I’m getting at. John is in business and he needs to find the optimum way of making his business successful and this involves getting the most out of his crocs. This is partly why he established his farm so far south. You see during the winter, outside of breeding season, teh crocs slow down and require very little food. In fact the ideal is to breed them here in central Queensland and raise them further north where they can grow faster.

One thing that is deliberately selected for is fecundity. Females who lay lots of eggs pass this characteristic on to their progeny so these females are favoured as breeders. So to males who breed more effectively are favoured. But behaviours also figure in selection of crocs for breeding. For example a bullish male who beats up on, or chases away females is not going to last long at Koorana. He’ll more than likely be sold off to a zoo and soon be out of the breeding stock, while more peaceful males who can get along with females will be favoured. As one staff member said, we want lovers not fighters. I don’t imagine that this will result in a population of doe-eyed docile crocs, at least not in my lifetime, but I don’t doubt that this is a selection for tameness.

At the same time there’s selection for rapid growth rate. This is crucial because the faster that crocs grow, the less food they need to consume before they are killed and skinned. But this makes things complicated because it might be the case that there are linkages between growth rate which is selected for, and aggressiveness, which is selected against. It will be interesting to see which characteristic is more important and which needs to be accommodated to favour the other.

Then there’s scales. This is interesting because now we’re getting into the kind of selection that produces morphological changes. In the crocodile industry the more rows of belly scales, the finer the skin. In which case crocs which produce extra rows of scales – and this trait is heritable – are positively selected. So looking down the track we might imagine that the crocs being farmed will be quite different from their wild cousins. They should be more placid, faster growing, and with folds of skin on their bellies with countless rows of very fine scales. In the next post I’ll talk about how they might also have different responses to people.

 

Wingless birds of change

Ever wondered what chicken farming would be like if the chickens were six feet tall?  Emu farming comes close, only the birds have sharper claws and they don’t all scatter when you walk among them. They close in on you. Right now I’m in Marburg, Queensland to look at the particulars of emu farming and the directions that these processes are taking these birds. Is this a process of domestication or is this just the keeping of wild birds in captivity? That’s my guiding question at the moment and I’m keeping my eyes and ears open for signs that emu farming might be changing these bird populations along the lines of traditional domestication. But this is where it gets complicated. At birth emus are like many birds in that they imprint on whosoever gives them a lot of attention. So farmer Steve has to be sure to leave hatchlings well alone otherwise they imprint on humans and this causes a lot of problems down the track. Not least is that they try to mate with the human staff. So in this sense we could say that it’s essential to maintain a sort of wildness in them so that they’ll be more likely to mate with other emus rather than farmer Steve. But at the same time they can’t be too wild as some tend to get very aggressive and attack humans entering into the enclosures. These agro birds usually get removed to the ‘meat and feathers’ only paddock and are effectively out of the gene pool. But what about tame birds? Perhaps these birds are first to the feeders when farmer Steve fills them up, giving these birds a bit of an advantage over the others. Probably someone with time on their hands would be able to determine that but time I don’t have. Still, I really do think that there must be some sort of change going in the genetic makeup of the farmed emus and this is complexly woven into their developmental processes. Unsurprisingly it’s complicated. I also wonder about the wild populations if emus become domesticated. This is because a few other species that humans have domesticated – aurochsen and horses – disappeared from the wild. Some might call it extinction but on the other hand you could look at it as these animals carving out a new niche whereby they thrive in numbers far greater than their wild ancestors. And this brings me to crocodiles. The farming of these creatures has been said to be the way to save the species. I’m off to Rockhampton next to see how farming crocodiles might not just save, but alter the species.

Those sharp claws make for hazardous farming at times. Especially as emus show almost no fear of humans. See above.

Emu eggs are very heavy, dark green, and taste like egg. Interestingly the emus lay them beside the fences  and (to my great relief) don’t defend the eggs when you collect them.

There are none so cortically blind as cannot see

In the last post I talked about the bits of the brain that (normally) cooperate to make the rest of our bodies react fearfully to things like snakes. I highlighted the thalamus-amygdala pairing and how one send information to the other in advance of our conscious knowledge of whatever it is we’re reacting fearfully to. But in the end we do get to process the fear-relevant information and take control of our fear response, don’t we? Well, that depends on who this ‘we’ is that I’m referring to. If ‘we’ is the small percentage of the population who have brain injuries that cut the connection between the thalamus and the visual cortex, then think again. Or don’t think as the case may be, because what the eyes perceive will never reach the part of the brain that thinks about things that the eyes perceive. But that’s not to say it won’t be acted upon.

Here again is the picture of the see-through head that I used in the last post just to make this easier to follow:

As you can see there are two pathways along which fear-relevant visual stimuli travel. Both go through the thalamus and amygdala but only one pathway goes through the visual cortex for conscious processing. So in cases where the pathway from the thalamus to the visual cortex is damaged, we should still expect the visual information to reach the amygdala, right? After all the eyes are good, the thalamus and amygdala are fine and the pathway isn’t damaged. Well, it just so happens that the information does travel the low road intact and this folks, is called blindsight.

There’s someone who is famous in cognitive neuroscience although I don’t know his name. All I know is that his initials are G.Y. and he’s probably English. G.Y. is famous because he straddles the line between those who are cortically blind and those who can see normally. Following a car accident he suffered damage to only the right hemifield of his visual cortex, meaning that he is only  ‘bind in one eye’ although technically both his eyes can see. Consequently G.Y. is much sought after by cognitive neuroscientists because he is a test case and a control all in the one neat package.

In one experiment G.Y was shown images of male and female faces with fearful and happy expressions. These were shown separately to his left and right hemifields and he was required to push a button to identify whether the face was male or female. Throughout the trial G.Y. denied visual perception of anything presented to his right visual field, but still reported the feeling that ‘something happened’ when he was presented with the images. Something certainly did happen. In fact he correctly identified the sex of faces presented to his right (blind) side more than he did those presented to his left side – 76% compared to 63%.

In the second experiment G.Y. was presented with pictures of males and females with happy or angry faces and the angry female faces presented to his left visual field were accompanied with a loud noise – an unconditioned stimulus. The expectation was that the  angry female faces would elicit a fear response in his right (blind) hemifield because they should be associated with an aversive stimulus. But anyone who is human should know not to expect brains to act predictably. In contrast to the first experiment G.Y. identified the female faces presented to his right hemifield only 34% of the time. In fact he was significantly more likely to identify an ‘unseen’ aversively conditioned face as male. We can only guess what is going on although the fMRI showed the amygdala firing on all cylinders while G.Y. was shown the angry faces indicating a fear response. There was also activity in the superior colliculus and our old friend the thalamus indicating that some subconscious decision making was going on. So it looks like the bits of the brain that decide what is fearful and how to act make assumptions based on the nature of the stimuli. In fearful faces they seem to identify sex quite easily but with angry faces they seem to assume that if an angry person is making them fearful it must be a male. On balance it’s a pretty wise assumption.

 

 

The Organisational Structure of a Fear Corporation

I should begin this post with an advisory message: the following should be read while secured to a strong anchor point as it will turn your world upside down. I can’t overstate the awesomeness of what is revealed below. There’s also a fair wad of toilet humour which might be unpleasant as your world is being turned upside down.

In the previous post I discussed Snake Detection Theory and the experiments that showed people have a perceptual bias toward detecting snakes. Fair enough, I’ve had a few snake detection experiences and I certainly detect them better than I do my car keys when I’m in a hurry to go out. But what is the neurological basis for this detection bias? What happened in my brain when I found myself jumping in the air in response to a snake I didn’t even know was there?

The psychologist Joseph LeDoux explained all this when he mapped out the neural pathways that cause us humans to express fear. There are two different pathways that have become known as DeDoux’s High and Low Roads. Here’s a picture to give you a better idea of how these pathways transform visual information into fear responses:

As you can see, before it reaches the visual cortex, visual information travels through a primitive part of the brain called the thalamus. This overgrown soybean is like the front desk of your consciousness. It filters every bit of information and decides on where it should be sent. If it’s something from the peripheral vision that has no relevance to you it is hastily sent out the door. If it’s something that the upstairs department – consciousness central – is dependent on, then it’s sent along the high road to the visual cortex for conscious processing. If it’s something dangerous, i.e. a snake, the information is immediately copied and the equivalent of a red button is pushed at the front desk.

The first copy is very hastily made and the rather rough information is sent to another primitive part of the brain that we share with all vertebrates: the amygdala. Yes, lizards have these, as do fish and it’s as crucial to your survival as your seat belt . The amygdala quickly holds the information up against a bunch of templates of things that should be feared, such as snakes, heights, my dad, and if it finds a match the amygdala initiates a fear response. This is the physiological equivalent of an evacuation of the building. Hair is raised, heart rate increased, blood supply directed to the muscles, and if the information is sufficiently fearful, bowels voided. A literal evacuation.

But remember I said the information is quick and dirty. It has to be, as speed is of the essence and in terms of things like snakes, ignoring a potential danger can be a lot more costly than an over-reaction. Meanwhile the thalamus sends a better picture upstairs via the high road to the visual cortex for conscious processing. This is the copy from the good printer that has more detail to go on. And if the conscious processing confirms the presence of a danger then another signal is sent to the amygdala to keep on voiding those bowels. But if the information proves to be non-threatening. i.e ‘Oh it’s just a damaged power-lead lying across the ground,’ then a signal is sent to the amygdala to cancel the fear-response. Heart rate decreases, hair flattens, sphincter closes, and you calmly step on the power-lead, getting an electric shock from hell.

Now here is the awesome bit: Sometimes the amygdala doesn’t trust the information from the visual cortex and says, nope, I’m going to keep on voiding those bowels. No matter how hard you try to control your fear response you only have limited conscious control over your amygdala and literally none over your thalamus down there at reception. What this means is that there is no singular mind in a singular body. Our minds are actually bunches of connected parts, usually cooperating to get us through the challenges of day-to-day survival but not entirely trusting each other to send the right information. What’s more is that there is no separation between the mind and the body in this sense because there is no mind. Our eyes are no more separated as our thalamuses and amygdalae (my spell check is going crazy). So while you might think your upstairs department is quite special and separate from the rest of the organisation, it’s actually just another level of cognitive processing that is often at the mercy of the other departments. This is mind-body pluralism.

How does this relate to your own experience? Have you ever had your amygdala take over and send you scurrying? In the next post I’ll finally get around to the subject of blindsight. This is where the lines to the upstairs department are damaged but the rest of the organisation keeps on operating.

 

 

 

The snake in the grass, not in the tree, made us human

In the last post I described some conditioning experiments in which researchers tested whether it was harder to extinguish peoples’ fear of snakes as opposed to fear of innocuous things or modern dangers. These experiments eventually gave way to a new paradigm in which researchers tested whether people had a perceptual bias toward detecting snakes. In other words they wanted to know whether people more easily detected a snake in the grass than say, a daffodil.

To test this they set people in front of monitors, showed them sets of pictures, and recorded the time it took to identify the odd one out. So among a set of flower pictures they included a snake picture or among snake pictures they included a single flower picture. What they found was that people more quickly spotted the snake among flowers than the flower among snakes. What’s more, it made no difference whether it was a 2 x 2 matrix of pictures or 3 x 3. The time to detect a snake was equally as fast. This suggested that yes, people do have a bias toward detecting snakes over other things.

Source: LoBue and Deloache 2008

At the same time a primatologist named Lynne Isbell theorised that this perceptual bias is a very ancient thing among us primates. Isbell’s Snake Detection Theory holds that the threat from snakes, whether as predators or things stepped upon, was a key driver in primate evolution, and by extension human evolution, fostering key attributes such as orbital convergence, trichromacy, and even declarative pointing. In other words, it was snakes moreso than brightly coloured fruits that set us on our current evolutionary pathway.

In the next installment, I’ll describe how this evolved adaptation to the danger from snakes is expressed physically in our overgrown primate brains.

 

Learning to un-fear snakes

In February I wrote a post about an encounter with a snake and an explanation for my reaction to said snake. Well, I’ve been thinking about this a lot and I think it warrants more attention. In that previous post I mentioned Seligman’s Preparedness Theory as an explanation for my reaction. The theory goes that humans are prepared or more inclined to fear evolutionary relevant things such as snakes and heights in comparison to modern  dangers such as cars and power outlets. Consequently the part of my brain that is evolved to initiate a reaction to snakes sprang into action as I perceived a harmless tree snake in my peripheral vision and made me jump in the air before I even realised that there was a snake beneath my feet.

Preparedness theory was initially tested to death by Arne Öhman and associates from the University of Uppsala Sweden. There they created a conditioning paradigm in which research subjects were shown pictures of snakes, spiders, flowers and mushrooms, while at the same time given electric shocks for particular pictures. The electric shocks were thus the unconditioned stimuli, or the stimuli that would require no conditioning for people to fear them. The pictures were the conditioned stimuli; the idea being that an electric shock administered with a particular picture would condition the subject to fear that picture. The measure of a person’s fear in this case was skin conductance. If skin conductance was higher then that indicated a fear response. Sweaty palms are a pretty good indicator of fear.

Interestingly the researchers found that where people were given a shock they readily acquired a fear – recorded as an increase in skin conductance – in association with the photograph type with which the shock was associated. So in that sense, preparedness theory was not supported because it predicts a difference between pictures of snakes and spiders as compared to pictures of flowers and mushrooms with regard to how easily people acquire a fear of them. But the theory was not a write off just because of that finding. After conditioning the subjects to fear particular types of photographs, the researchers switched off the electrodes so that the subjects no longer received shocks in association with any types of photographs. They were interested in how quickly the conditioned fear was extinguished when an unconditioned stimulus was no longer associated with the conditioned stimulus.

As for the flower and mushroom photographs, once people no longer received a shock in association with such photos, the subjects’ conditioned fears were quickly extinguished. But surprise surprise, where subjects were conditioned to fear images of snakes and spiders, their fear responses took longer to extinguish. Even though they knew they were no longer going to receive an electric shock in association with a picture of a snake or spider, they still gave a higher skin conductance reading for longer. What’s more the reseachers found this effect not only in cases where pictures of snakes and spiders were compared with pictures of flowers and mushrooms, but where they were compared with pictures of modern fear-relevant dangers such as guns, knives, and power outlets. So Seligman’s theory was not disproven. But this is not the end of the story. In the next installment I’ll describe the visual search test that took the theory further.