Why Might Some Personality Dimensions Appear Only In Some Animal Species?

Is personality unique to humans?

By Adam Hart
Professor of Scientific discipline Advice, University of Gloucestershire

Bird — Image caption,
A squad from the University of Oxford has been studying boldness and shyness in great tits

We like to recall humans are pretty special.

Given our many achievements (I don't see chimpanzees landing probes on comets in the near future) information technology's a tendency that's largely justified.

But most of our thoughts aren't consumed with the magnificence or otherwise of our species. If we're honest, nigh of our thoughts are taken up by us as individuals.

Key to this conceit is the notion of our "personality". However, while we might retrieve that our sparkling personalities are something unique, psychological research tells the states that we can assess and measure personality using just five main personality dimensions.

What'southward more than, non only are our personalities not quite as special as we might think, contempo creature research tells us that personality is not even something unique to humans.

Inquiry into brute behaviour has normally focused on behaviour across a species, or more accurately, across a sample of that species. The approach has examined "boilerplate behaviour" and individuals just featured equally data points, with variation between individuals being of far less interest than the description and explanation of the overall behaviours observed.

Recently though, there has been a shift in this view. Inter-individual variation between animals is no longer existence dismissed as statistical noise but instead has been embraced and studied.

Equally you can hear in Frontiers on BBC Radio 4, insights from this individual-focused research take led united states of america to a far more nuanced view of behaviour and the evolutionary processes that have shaped information technology.

This approach to animal behaviour has go known as animal personality research. For a field notoriously sensitive to claims of anthropomorphism it might seem strange that a word so intrinsically human, with "person" so central to its etymology, has been embraced.

Simply really it'due south non and so surprising. Man personality is all about repeatable behavioural tendencies within an individual; in other words, we tend to respond to similar situations in a broadly predictable style.

Scientists probe personality differences in albatrosses using a plastic toy

Some of united states want to exist the centre of attention while others shy abroad. Extroverted people tend to always exist extrovert and indeed extroversion/introversion is one of the five dimensions of human being personality.

For an example of why personality is also a suitable word to employ to brute behaviour, consider a creature that is probably non top anyone's listing of personality candidates: the hermit crab.

Rather than growing their ain expensive protective shell, hermit crabs employ what Mark Briffa, reader in animal behaviour at the University of Plymouth, describes as a "dodge". They install their soft worm-like rear ends into an empty periwinkle or whelk trounce, poking their heads, claws and legs out of the opening to move around.

Image source, SPL

Some hermit venereal venture out of their shells more readily than others

When disturbed, they disappear dorsum into the security of their vanquish, merely venturing back out when they feel it's condom. What Mark has discovered is that some hermit crabs are bolder than others, with brave crabs resuming their out-of-the-shell activities far more than rapidly than shyer individuals. The crucial matter, every bit Mark says, is "if this behaviour is consistent within an individual then it is a bold individual".

Mark has indeed found that some hermit crabs are ever assuming; in other words they display a behavioural tendency that is consistent within an individual. Equally he explains, "that is a bit of mouthful to say, and then personality seems like a proficient word for it".

This consistency of behaviour inside an individual, or personality, has been documented in an ever-growing list of species, from obvious candidates like chimpanzees, through to cat sharks (who have social and solitary individuals) and even bounding main anemones. 1 group of animals where personality research is particularly far advanced is birds.

Wytham Woods, just outside Oxford is one of the most of import field inquiry sites in the world for studying the links betwixt environmental, evolution and behaviour. Here, Proessor Ben Sheldon, Dr Ella Coles and others from the Academy of Oxford accept been studying the personalities of a common bird, the great tit.

Image source, Andy Murch/SPL

Research in the Bahamas suggests that individual lemon sharks also have their own personalities

By communicable birds and exposing them to a novel environment (an aviary in which they are temporarily housed) researchers have been able to measure boldness and shyness in individuals and bear witness that individuals are consistent in these personality traits throughout their lives.

The researchers can besides follow birds over fourth dimension and this long-term approach allows the team to unpick the links betwixt personality and how successful those birds are at the fundamental business of producing offspring.

Dr Samantha Patrick of the University of Gloucestershire cutting her enquiry teeth in Wytham Woods simply has subsequently moved on to rather bigger birds - albatrosses. Samantha uses an intriguing, and frankly agreeable, method for determining how bold an albatross is.

Lying depression in the common cold grass of the Crozet Islands in the southern Indian Ocean, she pushes a toy plastic cow towards the birds with a stick. This novel stimulus allows her to measure the response of a bird, and to measure out that response over time.

What she has found, but like many other researchers on a diverseness of unlike species, is that different individuals have different responses (or personality types) but that individuals are consistent in their own response.

Research on birds and on an increasing variety of species shows that more often than not at that place isn't a "best" personality to be. The reason why there is personality variation betwixt different individuals is because there is variation in the surround.

Prototype source, AFP

Chimpanzees are idea to share the "large five" personality dimensions - such equally extroversion and agreeableness - with humans

Information technology'south a complex globe out there and that complexity changes over space and time. The environment doesn't stay abiding and in some environments, perchance those with plenty of hungry predators, it pays to exist a fiddling careful, a flake shy.

In other environments, or perhaps in the aforementioned place simply later in the year when food is scarce, information technology pays to exist bold, to exit there and notice those scant resources rather than cowering in a prophylactic hidey-pigsty. The shifting nature of the environment ways that the ultimate pay-offs to these different strategies finish up being more than-or-less equal and natural choice has led to a diverseness of personality types in animals.

Interpreting the evolution of animal behaviour in terms of their ecology is the realm of behavioural environmental and It should come equally no surprise to us that evolutionary and ecological perspectives have been so useful in explaining brute personalities.

Brute personality research is now starting to move towards a deeper agreement of how different personality types evolve and how they interact in groups of animals. Inquiry at Wytham Woods for example is looking at how personality types role in the groups of birds that grade foraging flocks over winter and how that mix of personalities affects success.

Although nosotros often like to remember otherwise, our personalities are just as much the products of natural pick and development as our upright opinion and large brains.

Creature behaviour researchers may have borrowed the concept of personality from homo psychologists but as social animals living in a complex globe it will be interesting to see what human psychology takes from creature research over the coming years.

Frontiers : Beast Personality is on BBC Radio iv on Wednesday 10th Dec at 9pm