Animal Personality: The Science Behind Individual Variation

Jill R.D. MacKay

• Publisher: 5m Books
• Year: 2018
• eBook ISBN: 9781912178933
• Topic: Biological Sciences
• Subtopic: Zoology
• Index: Biological Sciences

From 'scaredy cats' to 'moody cows', we often give animals personality when we talk about them, but does this have any basis in scientific fact? How can we tell if a cat is feeling fear, and how does a grumpy cow behave? What would make an animal an individual? And what makes them unique? Only recently has science confirmed that animals have distinct individual personalities, shown through behavioural research. Animal Personality introduces the fundamentals of personality science and research, describing the history of behavioural testing, and then drills into scientific measurement, recording and statistical analysis of individual personalities in animals. The author shows how the implications of animals having personalities affects how we treat and care for pets, farm animals and wildlife. Interesting questions are posed, such as what is the evolutionary reason for traits like fearfulness, aggression and sociability? Have we anthropomorphised animals' needs for social interactions? What are the neurological and genetic bases of personality? How has personality affected the domestication of wild species? And it questions long held beliefs about animal traits such as dominance theory. Animal Personality provides a fascinating and informed insight into the science of personality and its application to non-human animals. Ethologists and animal owners will find this an illuminating and thought-provoking resource. Dr Jill R D MacKay is a researcher and lecturer at the Royal (Dick) School of Veterinary Studies at the University of Edinburgh. She is extremely passionate about science communication and has been heavily involved with the Jeanne Marchig Centre for International Animal Welfare Education's outreach practices, including the Animal Behaviour and Welfare Massive Open Online Course. She coordinates and teaches on a range of animal welfare courses at the University of Edinburgh, from postgraduate to further education levels.

Chapter One
Non-Random Behaviour

What’s in this chapter?

This chapter introduces the phenomenon of individual behavioural variation in animals. We will look at some of the underlying concepts behind the study of animal behavioural variation, such as random and non-random variation, and how we use scientific methodology, such as hypotheses and theories, to try to predict animal behaviour.

The chapters in this book all have a few key messages. For this chapter, they are:

• It is possible to observe individual differences in the behaviour of animals.
• We can characterize these differences in terms of emotions, such as ‘fearful’, ‘bold’.
• These descriptors allow us to predict what an animal might do in any given situation.

I have a little cat named Athena. As a scientist, I’m interested in how the world works, particularly why humans and animals behave in the way they do. I often fly off to exotic locations, such as Bedford, to talk about my field at conferences. If I was to ask you to care for Athena while I was away, I might describe her in a number of different ways. She is female, about 3 years old, small in size and with a silver-tabby coat pattern. This information is not particularly interesting and nor is it helpful to you. At a stretch, it might help you to identify Athena out of a line-up. As Athena is the only cat in my flat, this sort of biological information is, frankly, pointless. Unless you have a particular dislike for tabby cats, this description would make you no more or less likely to look after Athena for the weekend. There is more that I could say about Athena. I could tell you she is a nervous cat, that she is a curious cat and that she is very vocal, especially when she doesn’t like her food. With this second set of descriptors, I have now provided you with far more relevant information with which to make your decision. With this information, you might infer that Athena would be difficult to look after and that the experience would be less enjoyable. You might start feeling cautious about this commitment. Compare Athena with Katie, another cat in my family, whom I would describe as an older, larger, tortoiseshell lady. She is docile, affectionate and easy-going. Who would you rather cat-sit, Athena or Katie? Was it the physical description of each cat that helped you make this decision? Or was it the description of their behaviour – their personality?

We describe and characterize the behaviour of animals because it helps us to make decisions about how we will handle and manage them. A farmer will treat an aggressive cow very differently to a calm one. Yet science has been relatively slow to catch on to the informative power of personality, historically viewing the variation in behaviour of individual animals as a ‘bugbear’ or a ‘nuisance’ (Slater 1981) affecting our experimental design and making our lives complicated. Moreover, for many years the scientific community was deeply critical of those who recognized the individuality that animals can possess, erasing it through the conventions of academic writing using the guise of objectivity. Did you bristle several paragraphs up when I asked who you were more likely to look after, Katie or Athena? If you did, you may be a grammar aficionado who knows that animals are typically referred to as that or which, such as in journalistic style guides for many publications (The Guardian and Observer 2015). It is a very simple academic convention that persists even today, removing any sense of an animal’s own individuality, or ‘agency’.¹

The legendary naturalist Jane Goodall, responsible for starting a boom in primate research, calls herself naive in retrospect for not recognizing how reluctant science would be to see the individuality in animals (Goodall 1998). She describes her irritation at a peer reviewer who demanded she remove every ‘she’ and ‘he’ from her manuscript detailing chimpanzee behaviour, replacing these offending words with ‘it’. A young woman, with no formal scientific training, Goodall didn’t have the academic grounding in 1960 to know that the scientific community regarded the study of animal personality as inappropriate.

Yet, animal personality is receiving more and more attention from animal behaviour scientists. In the year 2000, less than 50 papers were published on the subject. In 2012 there were a little under 500 (MacKay and Haskell 2015). Passionate and principled scientists like Goodall, who incidentally received her doctorate in 1965, not so long after her enraging peer reviewer, are only one component of this increased interest in animal personality. This rapid growth in interest about animal personality cannot be attributed solely to private rebellion of a few scientists, the phenomena itself must be something tangible. So, what is personality?

I would say that animal personality is the study of predictable and non-random behavioural variation. You might wonder why something so simple has taken so long to catch hold of the collective scientific imagination. There are scientific sounding words like ‘non-random’ and ‘variation’ in that description. Why is it controversial at all? Why would the scientific community be so reticent to accept ‘animal personality’? There must be more to the story, some unscientific element that I’m not revealing. Perhaps, like a Hollywood screenwriter, I’m throwing in those technical words like ‘non-random’ and ‘variation’ to make it sound as though I know what I’m talking about. There’s some truth to this. I do use these words deliberately, partly because I think it is important to underline that the study of animal personality is a science, but mostly because I think this definition is the very root of what animal personality is. To explain why the study of animal personality is a scientific subject, I think we ought to take a leaf out of Hollywood’s book and take a trip to Vegas.

While you are cat sitting for the weekend, I’m flying off to Las Vegas, where green felt tables are weighed down with brightly coloured chips, and dice are being thrown into a box to come up ‘snake eyes’. Las Vegas is the perfect place to talk about the difference between random and non-random variation because the casinos there have made their fortune on understanding the difference between them. Being the classy sort, I’m not going to stay too long in the reputable casinos, instead I’m going to find an unlicensed place to play one of my favourite games, Liar’s Dice.

Dice are random, for all intents and purposes. After shaking a die in your fist, once it leaves your hand and sails onto the table, any one of its six sides has an equal chance of landing face up. Think of this as the behaviour of the die, where only six behaviours are possible. No matter how many times you throw that die, you have no more information about what the die is likely to do on the next throw. The die is random; therefore, its past behaviour gives you no information about its future behaviour. As a scientist, I do need to place a caveat on this. If you understand every variable, such as the friction of the table you’re throwing the die onto and what side is presented upwards when you begin to shake, and you have a very powerful computer, you can calculate the odds of a certain side coming up ever-so-slightly more frequently than the others (Kapitaniak et al. 2012). But these odds are so long, and this kind of computing power so hard to come by, that Las Vegas is happy to consider dice random and so am I.

It’s worth talking about these dice in more detail, because Las Vegas was built on human inability to recognize randomness. The human brain is superb at recognizing patterns. In fact, some have argued that nothing can outperform it in pattern recognition. Our brains are so good at it that they often assume patterns exist where in fact none do (Foster and Kokko 2009). That’s why we develop superstitions and beliefs. Our brains refuse to believe that two events might be unconnected. For example, if we threw a die that landed on a ‘six’ five times a row, the odds of that full event occurring are one in six five times over, which we write as (1/6). If we throw the die a sixth time, what are the odds that roll number six will come up on ‘six’? It is still simply one in six, because the die has no memory; each individual roll has the same odds. Humans struggle with this concept. When writing this paragraph, I double checked my very simple arithmetic many times, unwilling to believe it. Las Vegas rakes in gamblers’ money on slot machines, the roulette wheel and the craps table, because humans cannot ‘do the math’ and instead seek non-existent patterns. We love to believe that the sixth roll will be in our favour. What if my assessment of Athena as ‘fearful’ is down to my human brain seeing a pattern that does not exist?

Earlier I mentioned how a sufficiently advanced computer could predict the outcome of a dice roll. There are easier ways to make dice more predictable, as Las Vegas knows all too well. By shaving an edge off one side, or drilling a small hole in the casing to be filled with lead, a die can be weighted to come up on a certain face more frequently than the traditional one in six chance. In this case, the more we throw the die, the more information we gather about what it’s likely to do the next time it is thrown. Loaded dice are therefore predictable and non-random. A well loaded die will reliably show its favoured side perhaps six times out of six, whereas a poorly loaded die may only show its favoured side every one in three rolls. After observing the die’s behaviour several times, we could say how confident we are in the strength of its loading, whether it was well loaded or poorly loaded. If we were very confident, we might place large bets, safe in the knowledge our gamble would likely pay off. If we were not so confident, we might place smaller bets, but still gamble differently than we would if we had a truly random set of dice. The difference between random and non-random behaviour is confidence in our ability to predict the result.

It is not much of a stretch to imagine that animal behaviour can be predictable. The philosopher Descartes said as much when saying that animals were biological automaton, that any given input into their machine would result in the corresponding output. The concept of animal personality takes the idea of predictability a step further and says that individual animals differ predictably from one another, that no two animals will be predictable in precisely the same way. Further, animal personality suggests that this predictability gives some insight to how the animals feel about the environment they’re in.

The ability to make predictions about what animals will do based on our prior experience would have been extremely valuable to our ancestors. Indeed, the usefulness of predictable behaviour may be one of the reasons animals, including humans, evolved personalities, rather than be endlessly flexible in our response to situations (Wolf et al. 2011). Take Athena’s response to just about any unexpected sound. She leaps to her feet, back arched, ears pricked, nose twitching and eyes wide to take in every bit of information about the cake tin I’ve just dropped in the kitchen. Given enough provocation she’ll dart to the bedroom, to the most secure part of her territory. This may be fair when a cake tin falls to the floor unexpectedly. A sudden surprise and unfamiliar noise may well be a potential threat to Athena. Even though she has lived a life of luxury and protection, she carries with her the instincts of her wild ancestors. Running away from potentially dangerous situations kept her ancestors alive long enough to reproduce and eventually bring about her existence. However, Athena also hides when the door bell is rung, a daily occurrence, and when the oven timer rings. Athena rarely distinguishes between truly new and startling stimuli versus a commonly heard stimulus. Athena seems to believe that all are worthy of a startled reaction. Better to hide under the bed than be caught out. One never knows when the vacuum cleaner may make an unexpected appearance. Not all cats are like this. Not even all the cats I’ve owned are like this. Through my experience with Athena, I’m able to broadly characterize how I think she will respond to a stimulus. As a pet, Athena’s survival is not greatly affected by her willingness to run away from a potentially dangerous situation, but we can see how this would have helped her ancestors in the wild. Where environments are unpredictable and dangerous, this kind of active response is useful, but where environments are calm and non-threatening, the active response is a waste of energy. From an evolutionary standpoint, this lack of flexibility seems baffling. If we were to design a cat from scratch it would be better if Athena could save her energy for when she needs it. It appears that she cannot be flexible in her behavioural responses. Something forces her to always respond in a particular way. In biology, we would say she has limited behavioural ...

Table of contents

• Cover
• Half Title
• Title
• Copyright
• Contents
• Preface
• Acknowledgements
• Chapter 1 Non-Random Behaviour
• Chapter 2 The History of Personality
• Chapter 3 Personality and Welfare
• Chapter 4 Measuring Personality by Proxy and by Construction
• Chapter 5 Experimental Design and Personality
• Chapter 6 Fearfulness
• Chapter 7 Aggression
• Chapter 8 Sociability
• Chapter 9 Miscellaneous Personality Traits
• Chapter 10 What Is Personality?
• Chapter 11 The Science of Individuals
• References
• Index