That some birds seem “clever” has been noted for many years – talking parrots, tool-wielding crows, memory-storming jays. But what does clever mean? How can we apply what we understand as “brainy” to a bird? Let’s take a look into the avian mind.
But who deems which knowledge, which skills?
Einstein is considered to be one of the smartest people to have ever lived, yet he was not very good at school, suffering from speech problems from a young age. Seeing little potential in him, his professors declined references for employment. Struggling to find work as a result, he eventually got a job as an office clerk in Switzerland. This turned out to be perfect, as he could do the job quickly, and spend the rest of his time researching physics, his core passion. Maybe somewhat too modestly, Albert himself didn’t attribute his stunning insight into this field as “intelligence”, but simply perseverance – “Genius is 1% talent, 99% hard work”.
To determine the intelligence of someone or something requires the understanding of what intelligence actually is. Dictionary attempts offer the somewhat dismissive sentence “the ability to acquire and apply knowledge and skills”. But who deems which knowledge, which skills? Say there’s a boy who can’t perform simple arithmetic, or write a letter; is he stupid? He can, however, whittle a fully functional gearbox and drive shaft for a go-kart from a fallen tree; is he clever?
The definition of intelligence has been hotly debated over the years by many people; from a fifteen-page thesis to a terse handful of words: “the capacity to acquire capacity”, or the circular “intelligence is what is measured by intelligence tests”. Robert J. Sternberg, a leading light in this field of understanding, once uttered the aside, “there seem to be almost as many definitions of intelligence as there are experts asked to define it”.
Practical intelligence can be summed up as “street smarts”.
Sternberg’s theory suggests it consists of three parts: practical, creative, and analytical intelligence: a combination of these different assets comes together in the form of mental activity enabling an individual to deal with (or not) real-world events relevant to their life. Practical intelligence can be summed up as “street smarts” – finding solutions to new problems by applying what you have learnt from experience. This differs quite a lot from the rather stuffy “traditional” notion that has lingered for decades: IQ (Intelligence Quotient) tests. Subsequent research has shown that people who can ace those don’t necessarily do all that well in other factors of life that require creative or experiential steps. The boy cannot tell you how old Mary will be when she is twice as old as her brother, who at 4 years old is three times younger than Mary*, but he can design a car that will knock your socks off.
If we find it difficult to define intelligence when dealing with humans, it is infinitely trickier when trying to apply it to animals. Studying intelligence in birds is therefore referred to as cognitive ability by those engaged in avian research.
Does size matter?
One approach to deciding whether an animal has the capacity to display cognitive ability was to note the size of its brain to its head-space volume. Decades of research indicated it may have had some truth to it, until it was discovered that it is actually those purveyors of information called neurons that matter. Most importantly how many there are, how densely arranged they are, and whereabouts in the brain they are located.
We have 86 billion neurons in our brains, with 16 billion packed into our cerebral cortex, the main computer in charge of our attention, perception, awareness, memory, language, and consciousness. The rest are in our cerebellum, the part responsible for coordinating voluntary movements, as well as balance, coordination, and posture. This equates to a 20% / 80% split. Brain size as an indication of cognition still persists in our language to this day, seen in phrases such as “of little brain” and “small-mindedness”, but we now know we should be saying “well, your neurons are widely spread” or “he’s a cortex short of a billion neurons”, and other pithy phrases I’m yet to think of.
As it turns out, bird brains are relatively large with respect to head size, like the great apes and us, which isn’t a surprise considering their hearing and eyesight has been shown to be exemplary. But where are their neurons? In 2014, a team of Brazilian scientists analysed the neuron density of eleven species of parrot and fourteen species of songbirds. They found that overall, those birds have the opposite of us – 80% cortex, 20% cerebellum. Parrots and corvids had the most density of neurons in their cortex, suggesting what the team called a “large computational capacity” – in other words, who’s a clever boy then.
they can use tools to get other tools to access food
It was already known through various experiments over the years that corvids and parrots do indeed display the most striking cognitive abilities, and now here was the neuron count to back it up. New Caledonian crows have demonstrated that not only can they create tools out of wire, sticks or leaves to access food, they have also shown that they can use tools to get other tools to access food, something known as compound tool construction. Many parrots can “talk”, creating complex vocalisations by listening to us. One very famous parrot, Alex the African grey whose life was sadly cut short at the age of 31 by some unknown disease, learned over a hundred words in English for shapes, colours, and specific objects, even spelling out words using their individual letters.
Jays are considered one of the world’s most intelligent birds due to their food-caching abilities – many corvids cache food but an individual jay from a range of species caches around 8,000 acorns every autumn and remembers where it put them. This means they have developed long-term memory. This employs the use of various executive functions, brain-based cognitive processes. Jays therefore use the same mental skills we experience every day in our normal lives, that include stress tolerance, organisation, working memory (the ability to keep track of new things whilst doing other things), flexible thinking (finding alternative approaches to challenges), and self-control (restraint allowing us to plan, focus attention, and remember instructions).
Fish food and bottle tops
There have been numerous passed-on instances of birds learning new things, and a 1979 paper detailed a study of the use of cormorants in China, after anecdotal evidence persisted with the notion that the cormorants could count. Fishermen have employed the assistance of waterbirds for centuries. Tied to bamboo pole perches with knots lashed around their necks, not too tight but tight enough to restrict swallowing, the cormorants would dive into the waters at a shouted instruction or a tug on the rope, and drop any caught fish in a bucket; if a dive failed, they kept going until they caught fish. After catching seven, the fishermen would reward the birds by loosening the knot and when they surfaced with catch, they could eat it. Over a short space of time, after fish number 7 plopped in, the birds refused to dive if their knot was still tight, clinging on to the perch with the stubborn resolution of a dictator before the uprising. Once the knot was loosened, in they went, and fish number 8 was theirs. These birds could quite clearly count. The ability to count is also deemed an executive function.
this species didn’t learn how to get at the cream through the foil because they don’t socialise
The cover of the highly recommended book The Genius of Birds by Jennifer Ackerman features a blue tit pushing its head past the torn open edges of a foil top on a milk bottle to get to the cream below. At the beginning of the 20th century milk would be delivered to the doorsteps of British households in open-topped bottles. Milk contains lactose and is damaging to birds but the cream at the top is low in lactose and the fat contains much needed energy, and blue tits and robins frequently siphoned this off. During the Second World War, dairies placed foil tops on the bottles to help the contents last longer. By the 1950s, it was a familiar sight to see blue tits drinking through the foil, but not robins. Whilst robins can be just as innovative as your average blue tit, they are highly territorial and solitary except during breeding season. It has been reasoned that this species didn’t learn how to get at the cream through the foil because they don’t socialise. Many birds of the tit family live in large groups, they are gregarious, and can easily pass information to each other this way, and within the space of 5 years all blue tits in the UK knew to pop the foil lid. The cormorants would spend their fishing employment in large groups as well, watching each other, communicating. Corvids such as jays, crows and ravens are also gregarious, as are parrots. Combine this highly sociable lifestyle with their densely packed neurons and you have the winning traits of a very clever bird.
As bird lovers ourselves, we know that birds learn where the food is when we put it out; we know many birds find their way across thousands of miles of land and ocean every year and return to the same wintering or breeding site, some even to the exact same nest; we know that fledgling birds learn their species’ song by listening to the other males; we know that birds can mimic other birds as well as a huge range of noise-making objects like mobile phones, sirens, chainsaws. But what we don’t yet know is astronomical, and it is a credit to all the men and women out there who are trying to find out. When they know, they will share their knowledge, and that may well be the key to a clever world.
*Mary will be 16 when her brother is 8 😊