Human Ego In The Way of Appreciating Animal Intelligence?

Human Ego In The Way of Appreciating Animal Intelligence?

What separates us from animals? What makes us special? What makes us unique? The central premise of the book is to both show how animals (humans are animals, too, but for shorthand, this post, as does the book, will use the term) are more intelligent than we may think, but to also challenge the ‘moving of the goalposts’ by scientists with respect to high animal cognition.

For too long, animals have merely viewed been viewed as beings that react to stimulus alone (the ‘Cartesian view of animals as dumb automatons’ championed by Ernst Mayr) or as creatures that evolved to have useful instincts (while the latter is true, it does not paint the whole picture).

This post offers a glimpse (albeit a long one) into animal intelligence, particularly on areas that were previously considered to be uniquely human. The questions posed in the post title and at the start of this section will not necessarily be answered. Instead, if you are interested in finding out, I would highly recommend getting the book. Instead, this serves as the highlights that I have chosen. This will help serve as a useful point of reference to help me remember some of the key parts of the book that I found most interesting. Hopefully, it is interesting for you, also. Most of the content here is a description of an experiment and the result. I do not see this as a substitute for reading the book. There’s a lot that I haven’t included, particularly a lot of the commentary that brings the stories to life.

A note on the title

While it is true that we may not yet have sufficient knowledge to understand animal intelligence (we barely understand our brains), the book mostly is about human ego, particularly from experts, being in the way of recognising how smart animals are. Hence, the title I have adopted.

The weather outside is frightful

As the days started to get colder in early November, one morning, Franje, a female chimpanzee, decided to collect all of the straw from her bedroom. Carrying it under her arm on the island at Burgers’ Zoo, she made a nest to stay warm outside with her son. Most notably, she decided to take the straw out of her room while it was warm inside the heated building. She was not reacting to the cold, but, as one plausible explanation goes, she had anticipated the coldness that would follow based on the shivering she experienced the day prior.

Not Franje. Image by Marcel Langthim from Pixabay

So what? She must have seen someone else do it before. No, Franje had never done this before, and the experimenters had not seen any other chimpanzee do what she did, ruling out both imitation and rewards for behaviour. Was this a sign of future planning? That’s too big a leap to make from one observation alone, but it does strongly hint at that.

False claims

  • Only humans can think ahead (think about the future)
  • Only humans can care about the well-being of others
  • Only humans can take a vacation

The right kind of tests

If we fail to find a particular capacity in animals, our first thought should be whether we overlooked something and the second ought to be whether the test was appropriate for the animal being tested.

What we observe is not nature itself, but nature exposed to our method of questioning – Werner Heisenberg, 1958

People used to think that elephants were not capable of using tools. When a banana was placed outside their cage and a stick placed nearby, the expectation was for the elephants to use the stick to guide the banana into their cage, something that chimpanzees do instantly. An elephant grasps objects using its trunk, which they also use to smell objects. Since they have an excellent sense of smell, they know what it is that they are picking up. Using a stick, on the other hand, blocks their nasal pathways. This means that by using the stick, to pick up the banana, they are unable to both feel and smell it.

Photo by Tobias Adam on Unsplash

In the National Zoo in Washington, scientists hung fruit above the enclosure belonging to Kandula, a young elephant bull. The fruit was high enough that Kandula was not able to reach it without the use of any tools. Kandula was given lots of sticks and a sturdy square box. Ignoring the sticks, he kept on kicking the box until it was underneath the fruit. Stepping on the box with his two front legs, he retrieved the food. To make the test harder, the experiments tried placing the box in a different part of the yard. Upon looking at the front again, Kandula would need to recall what he did last time to get to the fruit, which he did! Kandula was even capable of retrieving the box from far away. What this example highlights is a well-designed species-appropriate test.

The absence of evidence is not evidence of absence

Another example of the need for the right kind of tests comes from the claim that only humans are able to recognise faces. Scientists previously neglected to realise that primates were tested on human faces instead of those of their own species. However, Lisa Parr, from the Yerkes National Primate Research Center in Atlanta, showed that chimpanzees were able to recognise faces of those of their own species. Apes could even detect which apes were a part of a family. After being presented with a photograph of a female, followed by two juveniles, they were able to identify the child of the female correctly. The consensus is now that chimpanzees’ face recognition abilities are on par with our own, and that it activates the same regions of the brains in the brains of humans and primates. Why couldn’t the primates distinguish human faces? One leading theory is that the primates were not as interested in faces that did not belong to their own species. The tasks didn’t interest them, so they were not motivated to try to perform their best.


If you think that chimpanzees do not have emotions then perhaps reconsider: furious apes showing temper tantrums for not getting their way to laughing ‘hoarse chuckles during roughhousing’. And that’s not to mention that when chimpanzees are bored, it leads to unrivalled cheekiness and playfulness.

The difference between humans and other animals is one of degree rather than kind – Charles Darwin

In one building that kept chimpanzees, the chimpanzees escaped and ran awol through the building before returning to their cages and closing their door before going to sleep. Those in the building may not have suspected a thing had someone not found chimpanzee faeces in the hallways. Why did the apes close their door on their way back in? Do they think about the future?

A classic example of showcasing boredom is a lab test with rhesus monkeys and chimpanzees. They were tasked with haptic discrimination: they had to push their hand through a hole, feel the difference between two shapes and choose the right one. With hundreds of trials per sessions planned, the monkeys did just fine. The chimpanzees, however, did well on the first dozen trials, showing that they were perfectly able to understand and carry out the task to a high standard. But then they started to get bored. They would then push their hands further down the tube to reach the experimenter, pulling at the experimenter’s clothes, making faces and banging on the dividing window to try to entice the experimenter to play with them!

Too hungry to learn

Testing animals under duress and expecting them to perform to a high standard in order to pass is not fair. Human children aren’t thrown into a swimming pool to test whether they’re capable of remembering where to get out from. And yet the ‘Morris Water Maze’ is a standard test on rats that puts them in a water tank with high walls. A submerged platform is what can save them, and the rats have to remember that while fighting for their dear lives. In the same vein, the Columbia Obstruction Method makes animals traverse an electrified grid after different periods of deprivation in order for researchers to see if their desire for food, seeing their children or to their desire to mate is more significant than their fear of a painful shock. Several labs keep their animal subjects at 85 per cent of their usual body weight to ensure food motivation.

De Waal wittingly points out that no rational person would suggest food deprivation for university students (hear, hear). The famous Harry Harlow, a primatologist, was an early assailant of the hunger-reduction approach. He believed that intelligent animals usually learn through curiosity and free exploration, which are likely to be dormant if they are fixed solely on food (i.e. you can’t think well when food-deprived).

For want of a better, less anthropocentric word, it is inhumane.

Animals have culture, too

In 1952, the primatologist Kinji Imanishi proposed that it is justified to talk about animals having culture if individuals can learn habits from one another that leads to behavioural diversity amongst different groups. A juvenile female macaque, called Imo, started the trend of washing sweet potatoes on Koshima Island, Japan. It was first copied by Imo’s mother, then those in Imo’s age group, followed by their mothers and then ultimately to almost all of the monkeys that inhabited the island! It became a tradition passed on from generation to generation.

We hit the jackpot

This is one of my favourite stories from the book. At Burgers’ Zoo one morning, scientists showed chimpanzees a crate filled with grapefruits. The colony was in the building at the time, where it spends the night, which is connected to a large island, where they spend their day. The apes were interested in watching the crate being carried through a door that led to the island. When the scientists returned to the building with an empty crate, pandemonium ensued. Twenty-five apes started “hooting and hollering in a most festive mood, slapping one another’s backs”. De Waal notes that he had previously never seed any animals so happy about food that wasn’t there. The apes deduced that the grapefruits must be on the island to which they would be returning to the next day. Trial-and-error learning is ruled out since this was the first time (and a one-off event) that this procedure happened.

The psychologists David and Ann Premack wanted to test a chimpanzee, Sadie, on inferential reasoning. An experimenter put an apple in one box and a banana in another. After some distraction, Sadie saw the experimenter eating either an apple or a banana. The experimenter left, and Sadie was free to examine the boxes. Sadie showed inferential reasoning straight away by going to the box containing the fruit than the experimenter was not eating. Gradual learning, learning from prior experiences, is not the case here since Sadie decided to do this both on the first trial and all subsequent ones. Let’s break this down. Sadie likely made two different conclusions here: 1) the experimenter took the fruit from one the boxes and 2) the other box ought to contain the fruit the experimenter was not eating. Most animals don’t make those sorts of assumptions. Chimpanzees, on the other hand, try to work on the sequence of events and fill in the blanks with the most logical explanations (sound familiar?).

Not Sadie. Photo by Amr Miqdadi from Pexels

In a separate test, the primatologist Josep Call showed apes two covered cups. The apes had learnt that one of the cups had something inside. When Call would take the tops of the cups off, the apes would choose the one containing the grapes. After covering the cups and shaking both in turn, the apes went for the one with the cup that made the noise of shaking grapes (without peering into the cups this time around). Even if Call would only shake the empty cup (which made no noise), the apes still went for the other, working via the process of exclusion (based on the absence of sound – you can’t fool them that easily). While we take inferences for granted, not all animals excel in this sort of task – take dogs, which perform terribly. Apes make logical inferences based on how they perceive the world to work.

Let’s jump into the ending of the story of the apes on the island with the grapefruits. Many apes ran straight over the point where the experimenters had hidden some grapefruits in the sand. The only way to know was from a few yellow patches that were visible. Like the others, Dandy, a young adult male, did not slow down after running over the spot. However, when the others started falling asleep in the sun, Dandy went back to that spot and dug it up to retrieve the precious grapefruits. Had he retrieved them when he first saw them, he would likely have lost them to the dominant males in his colony.


A banana was hung high up in the air out of reach for Sultan, a chimpanzee. A number of wooden boxes were scattered around; each of which alone was not tall enough for Sultan to climb on and then reach the prized banana. The first thing Sultan tried was throwing things at the banana in the hope that it would fall down, or drag a human by the hand towards it hoping that they would either reach it (reminds me of my nephew pulling me by the hand to fetch him some cookies) or act as a footstool for Sultan. When this failed, he simply sat around, as if he was thinking about what his next approach should be. He tried joining bamboo sticks to form a longer stick, which failed. At last, he stacked the boxes on top of another to build a tower that was tall enough for him to reach the banana! (This ‘aha!’ moment was compared to the Archimedes who was said to have jumped out of his bathtub after discovering how to measure the volume of submerged moments. He then ran naked through the streets of Syracuse, bellowing “Eureka!”, translated as “I have found (it)”).

Once more, trial-and-error learning is not at play here since Sultan had never done this before, nor had he ever been rewarded for his actions. Notably, Köhler found that once an ape found a solution, they then found it easier to solve similar problems, showing they formed causal connections.

Coordinating others

In a guest lecture, Emil Menzel once showed a recording of chimpanzees resting a long pole against their enclosure’s high wall. Some chimpanzees held the pole steady (akin to how we may hold a ladder steady for another), while others “scaled it to reach temporary freedom”. This was harder than it sounds, given that the apes had to avoid the electrified coils of wire and recruit help from others through hand gestures. Menzel’s commentary was “purely descriptive: ‘You can now see Rock grab the pole while glancing at others’, or ‘Here a chimpanzee swings over the wall’”.

The professor that invited him to talk criticised Menzel for being unscientific and anthropomorphic by claiming that the animals had planned this and that the chimpanzees had no intentions whatsoever (to escape). To much applause, Menzel replied that he said nothing of the kind and that if the professor had seen any plans or intentions, he must have seen it with his own eyes.

Intervention from someone impartial

At the Burgers’ Zoo, two female mothers were sitting in the sun while their children were playing together in the sand. The play turned into a “screaming, hair-pulling fight”. Both mothers knew that they could not break up the fight themselves; since when are mothers impartial? One of the mothers noticed the alpha female, Mama, was sleeping close by, and so went over and poked her into the ribs to wake her up. As the matriarch rose, the mother pointed at the fight. Mama took one step forward with a threatening grunt. Her wrath being feared by all, the two children promptly stopped fighting. What this shows is that the mother came up with an efficient solution based on a mutual understanding amongst chimpanzees.

Small acts of kindness

Are animals capable of showing kindness for one another?

A primate. Image by Margo Tanenbaum from Pixabay

Young female chimpanzees have been known to collect water in their mouths for an elderly female that can barely walk at all. When the juveniles reach the elder, they spit the water directly into her mouth (don’t judge them) so that she doesn’t have to make the trip to the tap herself.

Not Madam Bee. Image by Alfred Derks from Pixabay

The primatologist Jane Goodall observed how the daughters of Madam Bee, a chimpanzee in the wild, had grown too old and frail to climb into fruiting trees herself. Her daughter would kindly bring her some in addition to collecting some for herself. This shows that apes are not only able to devise ingenious solutions but also are able to comprehend another’s problem. That’s a fundamental ingredient in kindness and one we likely take for granted in ourselves.

Homology vs Analogy

Homology: common traits that come from a common ancestor. The human hand is homologous with a bat’s wing (both contain the same number of bones).

Analogy: animals independently evolve the same feature (this is called convergent evolution). Dolphins, ichthyosaurs (a now-extinct marine reptile species) and fish have similar shapes because they are in an environment where having a streamlined body with fins allows them to move quicker and be able to manoeuvre around more. None shared a common aquatic ancestor. Hence, their shapes are analogous.

Convergent evolution has meant that bats and whales both have echolocation, insects and birds have wings, and primates and opossums have opposable thumbs. It is also the reason why similar species are located far away from each other, such as “the armoured bodies of armadillos and pangolins, the prickly defence of hedgehogs and porcupines, and the predatory weaponry of the Tasmanian tiger the coyote”.

Moving further away to get closer

If an ape sees something it wants, it will search around for a bodily extension. For instance if an ape were to see an apple floating on the moat around the zoo island, the ape will look around for stones to throw at it so that it moves closer. The ape is moving further away for the goal in order to get closer to it, while also having in mind the sort of tool or tools that would be useful. There’s also the added worry that another ape will also see the apple and claim it for its own, so the ape has to act quickly. If an ape wants to eat the fresh green leaves hanging from a branch on a tree, they realise that the best tool in this scenario is something to climb on. The ape could spend half an hour trying to roll a heavy tree stump towards the tree with the fresh green leaves.

This brings us nicely on to the next section.

Tool use

It’s worth noting that apes know when a tool is required and when it is not. With the previous example of getting the green leaves from the tree, it is worth mentioning that there was an electric wire around the tree. Apes have been seen to check that the power going to the wires is on by touching the hair on the back of their wrists against the wires. If the power is off, no tool required.

“I feel that scientists holding to this definition [of humans being the only tool bearers] are faced with three choices: They must accept chimpanzees as man, they must redefine man, or they must redefine tools.” – Louis Leakey

Apes get most of their nutrition through seasonal fruits. When the supply of these is low, they opt for either nuts or palm pith. The latter is obtained through “pestle pounding”: a chimpanzee will stand on the edge of the tree crown, knocking the top with a leaf stalk. This makes a deep hole that the fibre and sap can be retrieved from. Chimpanzees rely on tools in order to survive.

The use of tools by animals has been proved to not come from the influence of humans through observations of animals in nature.

One of the things that came as a surprise was observing chimpanzees using tools as weapons (using a pointed stick for hunting), something that was thought to have only been done by humans.

As with all apes, chimpanzees appear to think before they act. This is especially the case for orangutans, but this also true for chimpanzees and bonobos despite being prone to being overexcited. They all seem to consider what effect their actions will have. This translates to being able to figure things out in their head instead of having to resort to trying it out to see if it works. As with our own species, a combination of the two – thinking about something and using trial-and-error – is used. The capuchin monkeys, on the other hand, are referred to as “a frenzied trial-and-error machine” and as overly active, overly manipulative and fear nothing. They exhaust lots of possibilities and hardly ever give up (kudos to them).

Now you see me, now you don’t

A thirsty orangutan. Photo by Susanne Karl on Unsplash

Orangutans have been observed tying knots into shoelaces and making instruments. A young male was seen connecting three sticks, which he had first sharpened, into two tubes to create a five-section pole to push down suspended food.

They are well known to be excellent at escaping. They may undo their cage patiently, day by day, week by week, while ensuring the loosened screws and bolts are not seen by the keepers until the very last moment.

Nut cracker

Over five centuries ago, a Spanish naturalist observed capuchins cracking nuts. This upset many since it meant that we are not the only ones that know about a Stone Age – our closest relatives are still one.

A capuchin in Costa Rica. Photo by Tj Kolesnik on Unsplash

The floating peanut task

Inspired by Aesop’s The Crow and the Pitcher fable, the floating peanut task consists of a peanut submerged into a tube. A female chimpanzee names Liza was given this task. At first, she tried kicking and shaking the tube, to no avail. She then suddenly turned around and went to the experimenter to pour water into her mouth. Upon returning to the tube, Liza emptied the water into the tube until the peanut was high enough in the tube to remove with her fingers. This was the first time that Liza was given this task.

Many orangutans and chimpanzees are able to solve this problem without any prior training. To contextualise how hard this problem, consider that only 58% of eight-year-olds find a solution and a mere 8% of four-years-olds do. Most children try to retrieve the peanut with the fingers before giving up.

Alex: more than just a parroting parrot?

Alex is an African grey parrot, purchased in a pet store in 1977, that has been studied for more than thirty years. Before Alex, the consensus was that bird brains are too small for advanced cognition. However, an African grey has a fairly large brain. Its brain is approximately the size of a shelled walnut, and it has a large area that behaves like a cerebral cortex.

An African gray parrot (not Alex). Photo by Tavis Beck on Unsplash

Alex had learnt the labels for various objects, such as keys, triangles and squares. When presented with such an item, he would say “key”, “three-corner” or “four-corner” respectively.

Speak and I shall baptise thee – A French Bishop to a chimpanzee in the early 1700s

The ability to recall what an object is an integral part of language. But that is not to say that Alex understood language. Apes are able to communicate with one another, but their language is limited. Their language lacks the syntax and recursivity that makes our own languages so versatile.

While we express our thoughts and feelings through language, it would be wrong to conclude that language is necessary to have those thoughts and feelings in the first place. At times, we may find ourselves in situations where we know how we are feeling but are unable to express it in words. Preverbal children have thoughts and feelings without being able to express it verbally. Thus, while language helps humans think, it is not necessary for humans to think.

For far too long, animals in general, and birds in particular, have been denigrated and treated merely as creatures of instinct rather than as sentient beings – Irene Pepperberg

Back to Alex. He is capable of answering “wool” when asked what material an object is made up. That’s not rote memorisation. What he is doing is collating his understanding of the shape, colour and feel of the object while connecting that the shape, feel and colour of wool (although, it would have been interesting to find out if Alex made that judgement based on a particular attribute as opposed to a combination). When presented with two keys and asked “what is different?”, he would answer “colour”. When asked “which colour bigger?”, he would respond “green”. The questions and the stimuli varied all the time. This meant that in order for rote memorisation to be at play here with labelling items, Alex would need to have a colossal memory to be able to store all of the different permutations. If that in itself wasn’t impressive, Alex was able to answer questions without even seeing the object. When asked what the colour of corn is, without being able to see any corn, he would answer “yellow”. A lot of data had been collected on Alex before his death in 2007. Both The New York Times and The Economist deemed him worthy of obituaries.

One of my favourite anecdotes of Alex is when he saw Irene storm around the lab while frustrated. In response, Alex told her to “calm down”. This expression is likely to have been directed to Alex in the past when he was previously excited or agitated. Nonetheless, how different is this to surprised parent hearing their child use a peculiar word or phrase.


Koko was a gorilla that was taught sign language. When shown a zebra, he signalled “white” and “tiger”. Or how about another of my favourites: when the sign-language-taught Washoe, a chimpanzee, called a swan a “water bird”.

It may be tempting to look at all of these examples and leap to the conclusion that perhaps, after all, some animals are capable of understanding language. De Waal rightly points out, however, that we first need to find out about the ratio between hits and misses across everything they say. It may well be the case these few shining examples are in the midst of tens of thousands of gibberish.

De Waal believes that humans are the only linguistic species. There is currently no substantial evidence to support symbolic communication as rich as functional as ours outside of our own species. Yes, other species can communicate. They can express emotions and intentions, but their communication is limited by not having syntax as infinite as our own. Communication among animal species seems so far to be constrained to the present.

A baby vervet monkey. Image by Sophia Nel from Pixabay

With language, honeybees can communicate to others in its hive the locations of far away nectar. Monkeys have some predictable sequences that resembles basic syntax. Vervet monkeys in Kenya have different calls for leopards, eagles and snakes. Different signals are essential here because different actions need to be taken depending on the type of predator that is close by.

Evolution is an iterative process: something doesn’t come about all of a sudden without having antecedents. New traits come about from existing structures. The part of the brain that is central to human speech is the Wernicke’s area, which the great apes also have, where it is larger on the left side of the brain than it is in ours. One question that stems from this is what that part of the brain was doing before we used it for language. One of my own hypothetical questions is whether the great apes will develop a language of their own that is comparable to ours.

Human speech is dependent on many connections, the FoxP2 gene being one. The FoxP2 gene also affects the “fine motor control of birdsong”. Human speech and birdsong are results of convergent evolution; humans and songbirds have at least fifty genes in common just for vocal learning.


Apes without linguistic abilities are capable of performing well on cognitive tasks such as mazes. Nonetheless, language is important because it allows you to tell an ape something that he or she doesn’t know. The famous Kanzi is a bonobo that communicates through pressing symbols on a keyboard. A game where apes had to put three puzzle pieces together to form a portrait was given to Kanzi. At first, Kanzi would take a piece of a bunny face and try to connect it to Sue Savage-Rumbaugh’s face (the researcher that worked with Kanzi). However as Kanzi understands human language, Savage-Rumbaugh would say to him, “Kanzi, we’re not making the bunny, put Sue’s face together.” He would then stop using the bunny face and construct the puzzle for Sue Savage-Rumbaugh’s face. In short, those that understand language are capable of performing at a much higher level on cognitive tasks since you are able to help them, instead of their understanding of the task remaining as a black box.

When Savage-Rumbaugh asked Kanzi to “Put the key in the refrigerator”, he would pick up the keys, open the fridge and put the keys inside. When asked to give his doggy a shot, he would pick up a plastic syringe and inject the needle into the stuffed toy dog.

Kanzi has been trained with many words through hearing them being spoken while wearing headphones. However, his ability to recognise words does not explain why he appears to understand complete sentences.


In 2007, a young male chimpanzee, called Ayumu, performed far better than humans in a memory test. On a touchscreen, Ayumu can, given a series of numbers from 1 to 9 in random order, tap them in the order in which they appeared on the screen. Reducing the time in which the numbers appear on the screen did not impact his performance. Humans, by contrast, perform less accurately when the display time is reduced. De Waal himself could not remember more than five numbers at a time while staring at the screen for many seconds, whereas Ayumu can after seeing the numbers for a mere 210 milliseconds – quicker than you can blink. In the study, humans were able to be trained to Ayumu’s level with up to five numbers. Ayumu can remember nine with an 80 per cent accuracy. No human has matched this yet. Faced against a memory champion known for being able to memorise a deck of cards, Ayumu came out as the “chimpion”!

But what makes us unique?

All right, animals are intelligent. “But what does it mean to be human”. As De Waal points us, the “but” is telling. It is asking the responder to forego all similarities and pinpoint what differentiates us from our distant relatives. De Waal uses an iceberg metaphor: there is a large space of cognitive, emotional and behavioural similarities between us and the primates. The differences lay in the tip of the iceberg, where there are only a few dozen differences.

Mirror, mirror on the wall, who is the smartest of them all?

The debate with what the big difference is has been said to be opposable thumbs, cooperation, humour (seen a chimpanzee lately?), altruism, language or the anatomy of the larynx. The debate may have begun with a debate between Plato and Diogenes about a succinct definition of the human species. Plato proposed that humans were the only creatures that were at once naked and walks on two legs. Diogenes responded by bringing in a plucked fowl into the lecture theatre, letting it loose while announcing “Here is Plato’s man”. The definition was then extended to include “having broad nails”.


Empathy is crucial for survival, and is something that we share with all mammals. Similar to how human parents need to be attuned to the desires of their children, mammalian mothers have to be sensitive to the emotional states of their offspring. Are they cold? Hungry? In danger?

On one occasion, an alpha male chimpanzee saved the life of a juvenile at a Swedish zoo. The juvenile had entangled himself in a rope and was choking to death. The alpha lifted the youth up (removing the rope’s pressure on the juvenile’s neck) and carefully unwrapped the rope from his neck. This required the alpha to understand the suffocating effect of ropes. If the alpha had pulled at the juvenile or the rope, he would have only made matters worse.

Another chimpanzee (none of the ones mentioned). Image by Susanne Jutzeler, suju-foto from Pixabay

At the Burgers’ Zoo, the keepers had hosed out some rubber tires when cleaning and hung them all on a horizontal log that extends the climbing frame. The chimps usually use these tires as drinking vessels. A female chimpanzee, Krom, wanted one of the tires that still had water in it. The tire she wanted was at the end of the row. She was unable to remove it by pulling at the tire. For over ten minutes, she kept on trying to pull the tire out while the other chimps ignored her. That is, all except Jackie, was a seven-year-old that Krom had taken under her care as a juvenile. As soon as Krom decided to give up and walk away, Jackie approached the tires and started pulling the tires in front of the last one off the log. When he got to the last one, he carefully took it off the log to avoid spilling any water and handed it straight to Krom. Without acknowledging Jackie in any way (which I think is harsh), Krom started scooping the water out of the tire as Jackie left. This showed that Jackie was able to both understand what Krom had wanted and was thoughtful enough to help her out.

Another capuchin. Image by Michelle Maria from Pixabay

Capuchins can be generous and are social eaters, like our species, sitting together in groups eating. When a pregnant female hesitates to go to the floor to collect her own fruits (capuchins are arboreal, and so feel safer higher up), other monkeys have been observed bringing more than they need and giving her some.

Image by Domenic Hoffmann from Pixabay

In one experiment, monkeys capuchins were separated with a mesh wide enough for them to push an arm through. One of the monkeys was given a small bucket with apple slices. The monkey with the apples usually shared some food with their empty-handed counterpart. They would sit next to the mesh divide and let the other one take food out of their hands or mouth. What is most astonishing about this is that the monkey with the apples did not need to share one iota; they could have stayed far away from the mesh and devoured the apples by themselves. If a capuchin saw that another had already eaten, however, it would not want to share any food with the other. On the other hand, if a monkey’s partner had already eaten without the other’s knowledge, the provisioned monkey would still share with the other. Food is precious, and a monkey would not want to share it with a monkey that it thinks is sated because it just saw it eat a large meal.

We, humans, show empathy from a young age. Young children are capable of knowing what another wants. De Waal wittingly notes that not all make use of this, which explains why there are two types of gift-givers. Those that go out of their way to get a gift that you like and those that simply give you a gift that they like.

Finders keepers

Charles Menzel let a female chimpanzee called Panzee watch as he hid food in the pine tree forest surrounding Panzee’s enclosure. Menzel would dig a hole in the ground to hide M&Ms or put a piece of candy in some bushes. Panzee was in her enclosure while Menzel was hiding the food and, therefore, required help from humans to retrieve the desired food item. Sometimes, Menzel would hide food after everyone else had left, which meant that Panzee had to wait until the following morning to see anyone that she could try to recruit for her cause. The following morning, the caretakers arrived, unaware of the experiment Menzel was conducting. In general, the caretakers have a high opinion of the apes’ mental skills, which is important because it meant that they would take them seriously. At first, the caretakers were surprised by Panzee’s behaviour but understood before long what she wanted them to do. Panzee would point, beckon, pant and call to help the caretakers find the items in the forest. Absent of her instructions, the caretakers would be none the wiser about where to look. Panzee never pointed in the wrong place or asked them to go to a place they had already visited, showing a clear ability to recall where the items were and what had already been found. This is much harder than it sounds. Don’t forget that Panzee had to communicate with a member of another species.

One young female grunted at De Waal from behind a fence with shiny eyes (suggesting she knew something) alternated with pointed stares at the grass near De Waal’s feet. De Waal was confused about what the young female wanted until she spat on the grass. This helped him notice a small green grape in the grass. After giving her the grape, she ran to another spot and repeated her actions to collect three grapes that the caretakers had dropped.


Victoria Horner and Andrew Whitten ran experiments on twelve orphan chimpanzees at Ngamba Island, a sanctuary in Uganda. The juvenile chimps grew attached to Horner and started to follow her lead. In this experiment, apes proved smarter than humans. Horner would show the juveniles that pushing a stick into holes in a plastic box would make candy come out of those holes. The catch here was that there was only one hole that actually released any candy. When the box was made out of black plastic, it was too hard to determine which holes were the dummy holes. With the transparent box, it was clear. With the transparent box, the chimpanzees only followed the steps Horner made on the hole that released the candy. By constrast, human children copied everything that Horner did, including the moves that led to no candy on the dummy holes. This highlighted that the human children did not grasp the problem itself and resorted to mere imitation to get the candy. The apes showed selective copying.

The word fashion was coined by Köhler in reference to animals. His apes used to invent new games regularly. They would march in single file around a post, in synchronisation to the same rhythm. They focused on stamping one foot while the other touched the ground lightly. If this wasn’t amusing in and of itself, they also moved their heads from side to side in the same rhythm. Or as De Waal puts it: “as if in a trance”. One meme was observed in a chimpanzee sanctuary in Zambia where one female was the first to place a strand of grass into her ear. As years went by, other chimpanzees copied her “look”.

Some alpha males would storm around while banging on a metal door to make his presence be heard. It is a scary thing to behold; mother chimpanzees keep their children close by. After the alpha male is finished, young infant males would copy their role model by banging on the same door.

Social skills

Hierarchy is everything with chimpanzees. When two females are tested inside a building at the same time, one will go through the task while the other will wait. The latter hardly takes rewards and does won’t even touch the puzzle box, computer or whatever apparatus is being used. The reason for this isn’t to do with interest: the second female may be equally (if not more so) eager to carry out the task than the first. It is a matter of submission. The second “knows her place”, so to speak, and allows the first to dominate. This holds true even if the two females get along well out in their group and are the best of friends.

Conflicts are hardly ever just between two individuals. Chimpanzees tend to bring others into the fold. There could be ten or more chimpanzees running around, threatening and chasing one another. Every individual tries to form as many allies as possible to strengthen their position. Chimpanzees that were losing would try to recruit their friends by stretching out an open hand in desperation. They also were proactive in trying to mollify the friends of their rivals. To know who the friends of your enemies are requires ou not only to recognise your relations with B (your enemy, say) and C (the friend of your enemy, B) but also how B and C relate. De Waal refers to this interconnected triangle as triadic awareness. He also points out that without triadic awareness, human society could not operate.

You may assume, as I did, that alpha male chimpanzees are the strongest out of the males in their group. That’s not always the case. A small, weaker male could become alpha by having formed the right allies. One of the ways they gain support from others is by grooming.

Chimpanzees have been described as having “Machiavellian intelligence” – the notion that the end justifies the means. De Waal is firmly against this as he believes they show strong social skills that don’t warrant that label. For instance, a female chimpanzee (likely to be the alpha female) will resolve a fight between two juveniles over a leafy branch by breaking the branch into two and handing one branch to each chimp. Or when a chimpanzee helps a limping, injured mother by picking up her child to carry the child for her.

A baboon (I can't tell if it is from an animated movie). Image by Marzena P. from Pixabay

In a baboon or a macaque troop, a female’s rank in the hierarchy is almost entirely dependent on the family she comes from. The daughters of high-ranking females will, in turn, become high-ranking. It isn’t possible to move up or down the hierarchy. When a female attacks another, third parties defend the stronger female to preserve the hierarchy. The daughters from the highest-ranking families are able to exploit their high rank by starting fights with whoever they want, knowing that they are unstoppable.

If a macaque becomes the victim of an attack, they like to take revenge by attacking a less powerful member of the attacker’s family.

Captive chimpanzees go beyond respecting those of higher rank to themselves. When the director of a zoo visited and started ordering people around (e.g. telling them what need to be cleaned, what needed to be moved, what could be done better, etc.), he portrayed himself as the alpha that others feared and were submissive to. Even though the chimps had hardly interacted with him, they treated him with the utmost respect by making submissive grunts to him from far away, something that they did not do for anyone else.

When it comes to peace-making between males, that’s best left to the females, particularly the highest-ranking females. They intervene when two males are unable to reconcile. Why can’t other non-involved males be the peacemaker? Since male chimpanzees are prone to frequently forming alliances, they are never seen as impartial. If they even tried to cause peace, they would be seen as another party in the conflict.


In the 1930s, Meredith Crawford ran an experiment to test the cooperation on apes. Food had been put on top of a box. Two youngsters, Bula and Bimba, had to pull at the ropes attached to their box outside their cages. However, the box was too heavy for one of them to pull by themselves. Their pulling was astonishingly synchronised (De Waal describes as “so well coordinated that you’d almost think they were counting – ‘one, two, three … pull!’”). In the second part of the test, Bula had been fed so much that she wasn’t as motivated to pull so much to get more food. Bimba got her compatriot to help by pushing Bula’s hand towards the rope or by a poking her. After the food had been reached, Bula didn’t collect much and left nearly all of it to Bimba. Why did Bula work so hard if she wasn’t interested in the reward? Reciprocity is the likely answer. Bula and Bimba live together, and so she did a favour for her friend with the expectation that when she next needs help, Bimba will be there for her. The cooperative pulling paradigm has also been tested on monkeys, hyenas, parrots, rooks, elephants and more.

Primates tend to prefer partners that cooperate eagerly and share the rewards. Capuchin monkeys tend to share more food with a partner that helped them retrieve the food than a partner whose (little) help was not needed. When chimpanzees go hunting, they prefer to share with fellow hunters than those that did not participate. The alpha male is not excluded here – if he didn’t help, he doesn’t deserve any – no free riders.

Chimpanzees are considered to be violent and aggressive. This description is based on how they treat neighbouring clans in the wild. This should not be an argument against their cooperative nature, though. On average, the murders on a field site occur every seven years. We should not forget that our own species considers forming allies and going to war as being cooperative. Chimpanzees hardly ever attack neighbours solo. Scientists not too long ago tested chimpanzees’ cooperation at the Lincoln Park Zoo in Chicago. They were able to fish for dipsticks for ketchup stored in holes in an artificial termite mound. At the start of the experiment, there were enough holes for everyone to fish by themselves. Every day, one hole was removed. Before long, there were hardly any. The holes could have been monopolised by a greedy chimp, but that wasn’t the case. Each chimpanzee took turns and patiently waited for their turn. That may seem to be the friendly sort of thing humans do, but I’m not sure. If we were tested and there was a scarcity of food (assuming we didn’t know it was a short-lived experiment), I reckon pandemonium would ensue, with more pushing and shoving than what you see in the Tube (London underground) at rush hour. Nonetheless, there’s no doubting that human cooperation is on a level of its own. We have organised ourselves at scale at a level not seen (as of yet, anyway) by any other species in nature.

Play fair

Sarah Brosnan and De Waal conducted an experiment on equal and unequal outcomes on pairs of brown capuchin monkeys. After completing a task, both monkeys were given cucumber slices and grapes (the monkeys prefer grapes). If they received the same reward, they would not complain. Yet if you provided one monkey grapes and the other the cucumber slices, you’re asking for trouble. The monkey given cucumber would happily eat their slices until they notice that their peer was getting grapes. The cucumber-allocated monkey would then throw a tantrum and throw away the cucumber slices it was given. Economists would label this as “irrational” behaviour since receiving something is better than receiving nothing. No monkey ought to refuse food that they would otherwise eat. Chimpanzees would be even unhappier by unequal outcomes. They protested both at being given less as well as more. This is similar to how some humans may react to unfair provisioning.

Kneel before Zod

Elephant bulls would pay respect to their leader by approaching him with an outstretched trunk and dipping the tip into his mouth to signify trust (yes, that’s a bit weird). In the chimpanzee world, dominant males expect their subjects to crawl in the dust while making submissive grunts. Don’t run away thinking we’re any different. Of course, there’s bowing before a monarch, but what about kissing the ring of the don or Saddam Hussein insisting that his subordinates put their nose under his armpit (charming guy).

Do animals think about the future?

Monkeys utilise their past experiences to make future ones, such as whether there is a safe landing pad for their jump between two trees, whether the branch is strong enough to handle the impact and so on. These are critical life-and-death decisions for them. The matriarch of an elephant herd in a drought may suddenly recall a drinking hole miles away that only she knows about. The other elephants trust her, and it may take days to reach the place where the water is. From a survival perspective, animals cannot afford to remain in the present because the present is ephemeral. However, most of the time, they think only about the near future, as opposed to the distant future.

In the 1920s, Edward Tolman, a psychologist, bravely declared that he believed that animals were more than stimulus-response machines. They are not purely driven by incentives. Otto Tinklepaugh, Tolman’s student, designed a test for this. A macaque watched someone place a leaf of lettuce or a banana underneath a cup. As soon as the macaque was released, they would go straight for the cup with the hidden food. However if the experimenter replaced the banana with the lettuce without the macaque knowing, the macaque would simply stare at the reward. The macaque would then start angrily shrieking at the experimenter’s deceitfulness. It would take a while until the macaque had calmed down and opted for whatever the lousy reward was. This was strange because animals were meant to connect behaviour with any reward. It shouldn’t matter what the reward was.

De Waal and others tested an adolescent chimpanzee called Socko with a hide-and-find test. Through a window, Socko would watch a human hide an apple in a large tractor tire in the outdoor enclosure while the rest of Socko’s colony was kept inside and away from sight of the outdoor enclosure. The colony was then released, with Socko being released. He first went into the tire, checked the apple was still there and then left it alone and walked away. After twenty minutes, everyone else was occupied. The coast was clear. He then went to collect the apple. Had he took it straight away, he could have lost it to a more dominant chimpanzee. This test with Socko was only done once. Years later, the test was being redone. Socko was now the alpha male, so could not be chosen. As the alpha, he would have no reason not to consume the fruit straight away since no mortal chimpanzee would dare question him. A low-ranking female called Natasha was chosen, instead. The experiment was nearly the same as before. Natasha watched through the window and was the last to be released. This time, a hole was dug into the ground, and the apple was buried. The spot was then covered with sand and leaves. The concealment was so good that the humans hardly knew themselves where they put the fruit. Natasha knew, though. She walked over the spot and waited ten minutes until she felt she wouldn’t be disturbed. While she started to dig up the fruit, Socko watched Natasha with awe. “It is not every day that someone pulls an apple out of the ground”, as De Waal puts it. Instead of approaching Natasha and claiming the apple for himself, he ran straight to the tire and looked in the tire for an apple. He felt that if food was being hidden, the humans might have hidden it in the same place as before. This was after one experience that had happened five years before this incident with Natasha.

This may be a coincidence, but Gema Martin-Ordas has been testing the memory capabilities of lots of chimpanzees and orangutans to see how much they could remember from past events. The apes had to find the appropriate tool to retrieve either a banana or a frozen yoghurt. The apes had seen the tools being hidden in the boxes. They had no problem with this task. Three years later, after having gone through numerous other tests, the apes were sent to the same room with the same setup. The investigator present was also the same as before. The apes that had taken the test three years ago knew exactly what tool they needed and where to find it, solving the problem in seconds.

Karline Janmaat found that apes (in the Taï National Park in the Ivory Coast) had stellar memory of where they had eaten before. They predominantly checked trees where they had eaten before in previous years. If they found lots of ripe fruit, they would make a mental note and return a couple of days later.

Chimpanzees, like some teenagers, despise waking up before dawn. Yet, Janmaat observed a group making a long expedition to a particular fig tree where they had previously eaten. They left early to avoid the fig rush. Figs are sweet fruits that many forest animals, squirrels and hornbills among them, crave. By arriving early, they ensured they had access to as much as their empty stomachs desired. Even more impressively, they would wake up earlier if they had to travel further. This implies that they account for the time it takes to reach their destination when planning travel routes.

Anthony Dickinson and Nicky Clayton wanted to test western scrub jays (known for hoarding) on what they could remember about cached foods. The jays were given two types of food to hide: perishables (waxworms) and durable (peanuts). Hours later, the jays first looked for their favourite food, the waxworms, before looking for nuts. Five days later, however, they did the opposite. They looked for the peanuts and didn’t bother searching for the waxworms. By that point, worms would have spoiled.

Lisala is a bonobo at the Lola ya Bonobo jungle sanctuary. This event happened not through an experiment but through observation, making it all the more striking. Lisala picked up a heavy fifteen-pound rock and placed it on her shoulders. Her baby was riding on her lower back. This was a heavy load to carry by any means. Lisala travelled for around half a kilometre. Every now and again, she would put down the rock and pick up items that were hard to identify by the observers. She would then put the rock back on her shoulders (and the baby back on her back) and continue her journey. After ten minutes, she reached a large slab of hard rock. Clearing the rock of debris with a few swipes of her hand, she would put down the rock and her child and put the items she collected, very tough nuts, on the anvil. The fifteen-pound rock she collected acted as a hammer. For fifteen minutes, she worked on breaking the nuts before leaving the tool behind. De Waal notes that it is hard to imagine that Lisala would have picked up the heavy rock without having the intention to find nuts to break. She also seemed to know where to find the nuts given that she planned her route to the anvil to go this way. This is comparable to seeing someone carrying a ladder down a road. We would not think that the person is carrying the ladder for no reason whatsoever (boredom and zombie apocalypse excluded).

At one zoo, a male chimpanzee called Santino would collect rocks from the moat around his enclosure every morning before the visitors arrived. He would stack the rocks up in a neat pile hidden from view. A lot of chimps want to impress the public by throwing rocks at them but find themselves empty-handed at the pivotal moment. Santino, on the other hand, was prepared. Most notably, he collected the rocks at a quiet part of the day rather than when filled with adrenaline when the visitors had arrived.

Mulcahy and Call let orangutans and bonobos choose a tool that they were not able to use immediately even though the rewards were visible. The apes were moved to a waiting room to test if they would hold on to their chosen tool to use later, even though the right time to use it would be fourteen hours later, which they did. Some have argued that this may have been because the apes had developed positive associations to the tool and were not anticipating the future. However, this has been addressed in another experiment where the apes were able to choose tools, as before, but now the rewards were not visible. The apes preferred a tool that they could use in the future over a grape placed next to it. This shows delayed gratification, a powerful thing that isn’t present in all humans. After choosing the right tool, when presented again with the same set of tools, they wouldn’t pick up the same tool again. If they had valued the tool above all else, their tool choice in the second phase should have been identical to their first choice. The apes realised that they didn’t need the same tool again, and so this time opted for the grape.

Caroline Raby lets scrub jays store food in one of two compartments in a cage that would be out of bounds during the night. The following morning, the jays would be given the opportunity to only visit one compartment. This led the jays to develop associations to hunger with one compartment, since the birds would spend their time there in the morning without breakfast. In the evening, the jays were allowed to store pine nuts in one of the two compartments. The birds put three times as many nuts in the hunger room than the breakfast room. What strikes me most about this example is the clever allocation. Sure, it sounds great that they put more pine nuts in the room where they think they would need it because they might go hungry in that room. But they also followed the “don’t put all of your eggs in one basket” dictum by still storing some nuts in the breakfast room. Just in case.

Nicola Koyama observed chimpanzees for over two thousand hours at Chester Zoo. She saw that the male chimpanzees that garnered more support from their peers that they groomed the day prior. This isn’t a mere coincidence. The males knew which confrontations they would incite and would actively recruit support in advance. This would ensure that their peers thought well of them when their support was much needed.


Capuchins have different ways of getting the seeds out of the Luehea fruits in the Costa Rican jungle. They can either knock the fruits or rub them against a tree branch. Adults tend to develop either technique but not both. In her fieldwork, Susan Perry found that daughters tend to prefer the method their mothers take. The same doesn’t hold true for the sons. Mothers act as a role model for their daughters but not their sons.

A vervet monkey in South Africa. Image by Sophia Nel from Pixabay

Erica van de Waal (not related to Frans de Waal) and Andy Whitten tested vervet monkeys in South Africa with open plastic boxes containing maize corn. Vervet monkeys love maize corn. The experimenters were in control of the supply. There were two boxes: one was pink and the other blue. One colour contained tasty corn, whereas the other had aloe in it, which meant it tasted revolting. Perhaps unsurprisingly, the monkeys learned to eat from the coloured box that contained the nice corn. The investigators then waited for infants to be born and for lots of migrant monkeys to come. They then observed monkeys eating from two boxes containing fine corn. All of the adults obstinately stuck to the colour they associated with good corn, which meant they could never find out about the better taste of the corn in the other coloured box. Likewise, twenty-six of the twenty-seven newborns learned to eat from the local popular colour. They would not eat from the coloured box that their mothers did not eat from. One exception to this was an infant whose mother was of such a low rank, and famished, that would sometimes eat the forbidden corn. The newborns of such mothers would also eat from the forbidden corn. Even if the male immigrants came in preferring a different colour, they would switch to the locally preferred colour, underlining conformity.

There is survival value in infants copying what their mothers do as opposed to trying out things for their own.

An experiment was conducted on two types of macaques: rhesus and stumptail monkeys. Children in both species were put together all day for five months. Rhesus are more cantankerous (jokingly compared to New Yorkers), while stumptails are laid-back and calm (compared to Californians). After being exposed to one another for such a long time, the rhesus monkeys became much more peaceful. They showed almost four times as many friendly reunions after fights than is common in their species.

Fun facts

Below are a list of facts that did not make it into the main body of the post, but I found them too interesting to omit entirely.


  • In other species, there is evidence for power alliances (politics), habits spreading (culture) and empathy and fairness (morality)

  • In biology, there is a difference between mechnanism and function. Animals can achieve the same end (function) through different means (mechanism). This happens frequently. Wasps, for instance, lack the larger brain size of primates and sheep. Nevertheless, they are capable of recognising faces despite only have a small set of neural ganglia. They evolved to achieve the same end (face recognition) through a different means.

  • Lots of animals have strong willpower when it comes to wanting to learn the things that it needs to do, such as the way that kid goats practice head butts to human toddlers who express an ‘insuppressible urge’ to stand up and walk.

  • As the muscles in the face in humans and chimpanzees are almost identical, it is thought that laughing, grinning and pouting of both species stems from a common ancestor

  • Hominoid = primate family of humans + apes

  • When brought up by humans, apes have been known to ride bicycles, light fires, drive golf carts, dine with a knife and fork, peel potatoes and mop the floor!

  • It is a popular misconception that the primates had stopped evolving while we continued. Our common ancestor stopped, but they went extinct a long time ago. We haven’t found our common ancestor yet, but hopefully, we will by discovering fossil remains

  • Flying isn’t, as we may think, something that comes naturally to birds. Instead, it is something that they have to learn. One of the hardest things with flying is landing (safely).


  • An arachnid can go for eighteen years without food! Imagine not eating anything for the first eighteen years of your life. It’s even more impressive when you consider that an arachnid’s life span is much shorter than that of a human.


  • A bat’s auditory cortex registers sound bouncing off objects and uses it to work out how far away from the object is, as well as how fast it is moving

  • The Clark’s nutcracker (a type of bird) stores over twenty thousand pine nuts in autumn across hundreds of locations than span many square miles. In winter and spring, it can find most of them again. Human memory is much weaker in comparison, but that is because we do not depend on memory in this way for survival as others do in a freezing winter.


  • Sheep use the same brain regions and neural circuits that we do when doing face recognition. Since sheep can recognise other sheep, moving sheep around between different flocks could cause more distress to them that we may have thought


  • The elephant brain has three times as many neurons in its brain (257 billion) than we do. Its neurons are in different regions; most are in its cerebellum. In our brains, the frontal lobes are considered to be the epicentre of rationality. Recent anatomical studies, however, show that they are not as exceptional as we may have thought. Some have classified the human brain as a “linearly scaled-up primate brain”, which means that no particular area is disproportionally large

  • Some may think that even though the elephant has more neurons than us, it isn’t that impressive given that most reside in the cerebellum (as opposed to the prefrontal cortex like our own). However, the cerebellum is important for us, too. During the Hominoid evolution, our cerebellum grew more than our neocortex


  • Chimpanzees, like our species, have difficulty in recognising faces that are turned upside down

  • There is an implicit rule amongst chimps than when something is in your hands or mouth, it is yours (similar to us)


  • Mirrors seem to introduce vanity. An orangutan called Suma at a German zoo liked to decorate herself in front of a mirror. For example, she has been seen putting a leaf of lettuce on top of her head like a hat


  • Apes learn gestures. If an ape stretches out an open hand, they could be begging for something. If an ape moves one arm over the other, they are showing their dominance. And these are just specific gestures. Much like humans, they also gesticulate when communicating. Chimpanzees hold out a hand to a friend that is eating (requesting the eating chimpanzee to share), but if a chimpanzee is under attack, they may hold out their hand to another to ask for protection. It’s highly contextual dependent

  • You don’t mess with an ape. Apes are stronger than us and have been to known to kill humans


  • Reciprocity is important for monkeys. Similar to humans, a monkey is more likely to be disposed to do favours if they received favours from that particular monkey


  • Primates that live in larger groups tend to have larger brains


  • The term anthromorphism, meaning ‘human form’, traces its roots back to the Ancient Greeks. In 570 B.C.E, Xenophanes expressed displeasure with Homer’s poetry since it defined gods as if they looked like humans. Xenophanes questioned why the gods could not look like another species and criticised the arrogance behind this faulty assumption

  • A group of people in an aphasia (unable to understand and construct language because of damage to their brains) ward were shown a speech by President Ronald Reagan. While they cannot understand the words, they follow along by closely observing facial expressions and body language. Since they are so attentive to non-verbal cues, it is very hard to fool them through lies. While the speech may seem normal to others, those aphasia patients were able to see past the lies through Reagan’s tone of voice

  • The DNA of humans hardly differs from bonobos and chimpanzees. It is only for historical reasons that we humans have the Homo genus to ourselves

  • It isn’t bipedalism that separates us from the rest of the animal kingdom. Several animals, chickens and hopping kangaroos amongst them, do the same. In some savannas, bonobos walk great distances on their feet in confident strides the way we do

  • Our brain is almost identical to an ape’s, including the different areas, nerves, neurotransmitters, ventricles and blood supply

  • In 1784, Johann Wolfgang von Goethe announced that he had found the biological roots of humanity: a minuscule bone in the upper jaw called the os intermaxillare. The bone had been found in other mammals, such as apes, but never in our species, which led anatomists to label the bone as “primitive”. This was a century before Darwin, which shows how long the concept of evolution had existed

  • There seems to be a tendency to denigrate other species, not unlike the way that some Caucasian males claimed themselves to be genetically superior. Some amongst us also make fun of the Neanderthals as brutes that lack any sophistication. That isn’t true. The Neanderthals had brains slightly bigger than our own, and some of their genes can be found in our own genome. Moreover, they, too, knew of fire, burials, hand-axes, musical instruments and more

  • The hippocampus is an integral part of the brain for memory and future orientation. Alzheimer’s usually starts with the degeneration of the hippocampus. The hippocampus in rats has a similar structure to our own


  • It is not necessarily true that cats are not as intelligent as dogs. When they don’t respond to calls, it is not because they do not understand. They can recognise their owner’s voice. It’s just that they don’t care

Dogs & wolves

  • A quarter of dog owners believe their dog to be more intelligent than most humans (E.O. Wilson, 1975)

  • When dog owners stare into the eyes of their dog, they get a quick increase in oxytocin. This is a neuropeptide that is a part of attachment and bonding

  • The brain of a wolf is approximately one-third larger than that of a dog

  • Wolves tend to be more self-reliant than dogs. If they are faced with a task they cannot do, they keep on trying. Dogs tend to look back to their owner for encouragement or help (wolves never do this).

  • Dogs make a lot of eye-contact with us. They have also “hijacked” the human parent pathways in the brain which makes owners care about their dogs the same way that they care about their children


  • They have been to known to unscrew a pill jar that is protected by a child-safety lock

  • The octopus brain is the largest and most complex of any invertebrate

  • Our brains have a centralised control centre, but the octopus’ cephalopod nervous system is distributed. They have two thousand suckers, and each has its own ganglion with half a million neurons. It also has ganglia along its arms. This allows for its brain to connect with “mini-brains”

  • In self-defence, they can change the colour of their skin (“out-chameleons the chameleon”)

  • They have a short life span: one to two years

  • The mimic octopus can impersonate other species


  • Dolphins have “signature whistles” (a unique high-pitched sound with a modulation). Females maintain theirs for the course of their lives, whereas the males change theirs to sound more like their closest friends, so that calls within a male alliance sound similar

  • A female dolphin called Bailey recognised the whistles of Alie, a female that she had lived with over twenty years ago