In July 2017, when Sean Spicer, then the White House press secretary, was discovered hiding in the bushes to dodge questions from reporters, I knew Washington politics had become truly primatological. A few weeks earlier, James Comey had intentionally worn a blue suit while standing at the back of a room with blue curtains so as to blend in. The FBI director hoped to go unnoticed and avoid a presidential hug. (The tactic failed.)

Making creative use of the environment is primate politics at its best, as is the role of body language such as sitting on a throne high above the grovelling masses, descending into their midst with an escalator or raising one’s arm so underlings can kiss your armpit (a pheromonal ritual invented by Saddam Hussein). The link between high evaluations of debate performances and the candidates’ heights is well known – taller candidates have a leg up. This advantage explains why short leaders bring along boxes to stand on during group photos.

Donald Trump’s bullying skills against his male rivals during the Republican primary were legendary. He defeated all his fellow candidates by puffing himself up, lowering his voice and insulting them with demeaning nicknames such as “Low-Energy Jeb” and “Little Marco”. Strutting like a male chimp, the Donald turned the primary into a hypermasculine body language contest.

But even though Trump had intimidation down to a T, this didn’t necessarily help him against his female opponent in the general election. Between the sexes, all bets are off. Fighting behaviour is bound by rules.

This was Trump’s dilemma: he was up against an opponent he could not defeat the way he could defeat another male. I have never seen as odd a spectacle as the second televised debate between Trump and Hillary Clinton on 9 October 2016. Trump’s body language was that of a tormented soul ready to punch out his opponent, yet aware that if he laid one finger on her, his candidacy would be over. He drifted right behind Clinton, impatiently pacing back and forth or firmly gripping his chair. Concerned television viewers live-tweeted warnings to Clinton like “Look behind you!” Clinton herself later commented that her “skin crawled” when Trump was literally breathing down her neck.

Trump’s demeanour was of barely contained anger, complete with an actual threat: he said that under his presidency a special prosecutor would throw Clinton in jail. Had he been a male chimp, he would have hurled that chair through the air or lashed out at an innocent bystander to demonstrate his superior strength.

The second Trump-Clinton presidential debate, in October 2016. Photograph: Julio Cortez/AP

Immediately after the debate, which Trump lost according to most commentators, the British politician Nigel Farage mimicked a feeble version of a chest-beat while gushing that Trump had acted like “a silverback gorilla”. Right away we got the primate parallels, also reflected in the observations from body language experts. The assumption here was that in order to be an alpha, one must be big and strong, ready to annihilate one’s rivals. I have never heard alpha references thrown around as freely as during this period. But the primate alpha male is much more complex and responsible than just a bully.

Merciless tyrants do sometimes rise to the top in a chimpanzee community, but the more typical alphas that I have known were quite the opposite. Males in this position are not necessarily the biggest, strongest, meanest ones around, since they often reach the top with the assistance of others. In fact, the smallest male may become alpha if he has the right supporters. Most alpha males protect the underdog, keep the peace and reassure those who are distressed. As soon as a fight erupts among members of a group, everyone turns to him to see how he is going to handle it. He is the final arbiter, intent on restoring harmony. He will stand impressively between screaming parties, with his arms raised, until things calm down.

This is where Trump deviated dramatically from a true alpha male. He struggled with empathy. Instead of uniting and stabilising the nation or expressing sympathy for suppressed or suffering parties, he kindled the flames of discord – from making fun of a disabled journalist to his implicit support for white supremacists. For the primatologist, the comparisons of Trump’s behaviour with that of alpha primates are therefore limited, applying more to his climb to the top than to the execution of leadership.

Emotions structure our societies to a degree we rarely acknowledge. Why would politicians seek higher office if not for the hunger for power that marks all primates? Why would you worry about your family if not for the emotional ties that bind parents and offspring? All our most cherished institutions and accomplishments are tightly interwoven with human emotions and would not exist without them. This realisation makes me look at animal emotions as capable of shedding light on our very existence, our goals and dreams, and our highly structured societies.

Since I don’t consider our own species to be much different from other mammals emotionally, and in fact would be hard-pressed to pinpoint uniquely human emotions, it strikes me that we had better pay careful attention to the emotional background we share with our fellow inhabitants of this planet.

When Aristotle labelled our species a zoon politikon, or “political animal”, he linked this idea to our mental capacities. That we are social animals is not so special, he said (referring to bees and cranes), but our community life is different thanks to human rationality and our ability to tell right from wrong. While he was partly right, he may have overlooked the intensely emotional side of human politics. Rationality is often hard to find, and facts matter far less than we think. Politics is all about fears and hopes, the character of leaders, and the feelings they evoke. Fearmongering is a great way to distract from the issues at hand.

Most astonishing are the euphemisms with which we surround the twin driving forces behind human politics: leaders’ lust for power and followers’ hankering for leadership. Like most primates, we are a hierarchical species, so why do we try to hide it from ourselves? The evidence is all around us, such as the early emergence of pecking orders in children (the opening day at a daycare centre may look like a battlefield), our obsession with income and status, the fancy titles we bestow on one another in small organisations and the infantile devastation of grown men who tumble from the top.

The depth of the human desire for power is never more obvious than in individuals’ reactions to its loss. Fully grown men may relapse into displays of uncontrolled rage more often associated with juveniles whose expectations are unmet. When a young primate or child first notices that its every wish will not be granted, a noisy tantrum ensues: this is not how life is supposed to be. Air is expelled with full force through the larynx to wake up the entire neighbourhood to this grave injustice. The juvenile rolls around screaming, hitting its own head, unable to stand up, sometimes vomiting. Tantrums are common around weaning age, which for apes is around four and for humans around two.

A male lowland gorilla. Photograph: Rex/Shutterstock

The reaction of political leaders to the loss of power is very similar. When Richard Nixon realised he would have to resign the next day, he got down on his knees, sobbed, struck the carpet with his fists and cried: “What have I done? What has happened?”, as Bob Woodward and Carl Bernstein describe in their 1976 book The Final Days. Henry Kissinger, Nixon’s secretary of state, comforted the dethroned leader as he would a child, literally holding him in his arms and reciting his accomplishments over and over until he calmed down.

For men, as Kissinger once said, power is the ultimate aphrodisiac. They jealously guard it, and if anyone challenges them, they lose all inhibitions. The same occurs in chimps. The first time I saw an established leader lose face, the noise and passion of his reaction astonished me.

Normally a dignified character, this alpha male became unrecognisable when confronted by a challenger who slapped his back during a passing charge and slung huge rocks in his direction. The challenger barely stepped out of the way when the alpha countercharged. What to do now?

In the midst of such a confrontation, the alpha would drop out of a tree like a rotten apple, writhe on the ground, scream pitifully and wait to be comforted by the rest of the group. He acted much like a juvenile ape being pushed away from his mother’s breast. And like a juvenile who during a noisy tantrum keeps an eye on his mother for signs of softening, the alpha took note of who approached him. When the group around him was big enough, he instantly regained courage. With his supporters in tow, he rekindled the confrontation with his rival.

Once he lost his top spot, after every brawl this alpha male would sit staring into the distance, unaccustomed to losing. He’d have an empty expression on his face, oblivious to the social activity around him. He refused food for weeks. He became a mere ghost of the impressive leader he had been. For this beaten and dejected alpha male, it was as if the lights had gone out.

One day in 1980, I received a call telling me that my favourite male chimpanzee, Luit, had been butchered by his own kind at Burgers’ Zoo in the Netherlands. The previous day I had left the zoo worried about him, but now when I rushed back, I was totally unprepared for what I found. Normally proud and not particularly affectionate to people, Luit wanted to be touched. He was sitting in a pool of blood, his head leaning against the bars of the night cage. When I gently stroked his head, he let out the deepest sigh. We were bonding at last, but under the saddest circumstances. It was immediately obvious that his condition was life-threatening. He still moved about, but he had lost enormous quantities of blood due to deep puncture holes all over his body. He had also lost some fingers and toes.

As soon as the veterinarian arrived, we tranquilised Luit and took him into surgery, where we sewed literally hundreds of stitches. During this desperate operation, we discovered that his testicles were gone.

Luit never came out of the anaesthesia. He paid dearly for having stood up to two other males who were frustrated by his sudden ascent. He had stolen their top spots just a few months before, which he was able to do because their coalition had fallen apart. The fight in the night cage marked the sudden resurrection of this coalition, with a fatal outcome.

In my experience, the better the leader, the longer his reign will last, and the less likely it will end brutally. We don’t have good statistics on this, and I am aware of exceptions, but generally a male who stays on top by terrorising everyone else will reign for only a couple of years and end about as well as Benito Mussolini. With a bully for a leader, the group seems to wait for a challenger then eagerly support him if he stands a chance. In the wild, bully males are expelled or killed, whereas in captivity they may have to be taken out of the colony for their own safety. Popular leaders, on the other hand, often stay in power for an extraordinarily long time. If a younger male challenges this kind of alpha, the group will side with the latter. For the females, there is nothing better than the stable leadership of an alpha male who protects them and guarantees a harmonious group life. This is the right environment to raise their young in, so females generally want to keep such a male in the top spot.

If a good leader loses his position, he is rarely expelled. He may drop just a few notches on the ladder and then age gracefully within the group. He may also still enjoy quite a bit of influence behind the scenes. I have known one such male, Phineas, for many years. After his alpha position was usurped, he settled in third place and became the darling of the juveniles, romping around with them like a grandpa, as well as a popular grooming partner for all the females. The new alpha permitted Phineas to settle disputes in the colony, not bothering to do so himself because the old male was exceptionally skilled at it. During these years, Phineas was the most relaxed I’ve ever seen him, which is perhaps understandable because, even though everyone thinks it must be great to be alpha, it is actually a stressful position. Researchers studying baboons on the plains of Kenya found that the top male is just as stressed as the males near the bottom of the hierarchy. The highest-ranking male is constantly on the lookout for signs of insubordination and collusion that might unseat him.

The first animal emotion studied – the only one that mattered to biologists in the 1960s and 70s – was aggression. In those days, every debate about human evolution boiled down to the aggressive instinct. Without mentioning emotions per se, biologists defined “aggressive behaviour” as behaviour that harms or intends to harm members of the same species. As always, the focus was on the outcome.

But behind aggression was an obvious emotion, known as anger or rage in humans, which also drives animal antagonism. Its bodily manifestations are the same across species, such as low-pitched threatening sounds (grunts, roars, growls). A male gorilla’s chest-beat tells us something about the circumference of his torso. During threats, animals inflate their bodies by raising shoulders, arching backs, spreading wings and puffing up hair or feathers. They show off weaponry, such as claws, antlers and teeth.

A frilled dragon in Batam, Indonesia. Photograph: Sijori/Barcroft

The males of our own species hold up their fists while thrusting out their chest to show their pectorals. The descent of the larynx at puberty in boys but not girls deepens the voice to make men sound big and strong. The purpose of these features is to intimidate and induce fear, so the aggressor will get his way. Most of the time it is effective, but of course if the goal is not reached, things may escalate. Anger is typically aroused by thwarted goals or by challenges to one’s status or territory. Showing anger is a common way of getting what one wants and defending what one already has.

Anger and aggression are sometimes described as antisocial emotions, but they are in fact intensely social. If you were to plot on a city map all instances of shouting, insulting, screaming, door-slamming and china-throwing, they would overwhelmingly be concentrated in family residences: not in the streets, or schoolyards, or shopping malls, but inside our homes. When police try to solve a homicide, their first suspects are family members, lovers and close colleagues. Since aggression serves to negotiate the terms of social relationships, home is where it typically occurs.

At the same time, close social relationships are also the most resilient. The reason human families manage to stick together is that reconciliation, too, is most common in these relationships. Spouses, siblings and friends constantly go through cycles of conflict and reconciliation, repeated over and over, to negotiate their relationships. You show anger to make your point, then bury the hatchet with the help of a kiss and some cuddling. Other primates do the same thing to protect their bonds against the eroding effects of conflict: they kiss and groom after fights.

For them, too, reconciliation is easiest with the ones they are closest to.

There is one domain, though, in which aggression is common and reconciliation rare. This domain received enormous attention in the mid-60s when Konrad Lorenz argued in On Aggression that we have an aggressive drive that may lead to warfare, hence war is part of human biology. The ensuing debate continues to this day. According to some, it is our destiny to wage war forever, while others view war as a cultural phenomenon tied to present conditions. Alas, the incredibly complex issue of human warfare is still often reduced to that of an aggressive instinct. From the beginning, apes have figured prominently in this debate.

At first they were seen as the poster children of our peaceful ancestry, because all they were thought to do was travel from tree to tree in search of food, like a frugivorous version of Rousseau’s noble savage.

In the 1970s, however, came the first shocking field reports of chimpanzees killing each other, hunting monkeys, eating meat and so on. And even though the killing of other species was never the issue, the chimpanzee observations were used to make the point that our ancestors must have been murderous monsters. Incidents of chimps killing their leaders, such as described above, are exceptional compared with what they do to members of other groups, for whom they reserve their most brutal violence. As a result, ape behaviour moved from serving as an argument against Lorenz’s position to becoming exhibit A in its favour. The British primate expert Richard Wrangham concluded in Demonic Males: Apes and the Origins of Human Violence: “Chimpanzee-like violence preceded and paved the way for human war, making modern humans the dazed survivors of a continuous, five-million-year habit of lethal aggression.”

A chimpanze colony in Liberia. Photograph: Zoom Dosso/AFP/Getty Images

Although this claim lacks archeological backing, it has fed into the popular storyline of human evolution, which turns on conquest, male dominance, hunting and warfare. We have a “man the hunter” theory and a “killer ape” theory; we have the idea that intergroup competition made us cooperative, and the proposal that our brains grew so large because women liked smart men. There is no escape: our theories about human evolution always revolve around males and what makes them successful.

Accordingly, humans in a “state of nature” (if such a condition ever existed) wage continuous war. Our only hope is civilisation, as Steven Pinker writes in The Better Angels of Our Nature: Why Violence Has Declined, a 2011 book that favours chimpanzees as the best model to understand where we come from. Pinker offers cultural progress as the solution to all our problems: we need to bring our instincts under control – otherwise we’d act like chimps. This distinctly Freudian message (Sigmund Freud saw civilisation as the tamer of our basic instincts) is deeply ingrained in the west and remains immensely popular. In the meantime, however, cultural anthropologists and human rights organisations abhor the inevitable implication that preliterate people live in chronic violence. This myth can be (and has been) used as an argument against these people’s rights. Perhaps a handful of tribes behave this way, but critics have argued that only serious cherry-picking from the anthropological record can support Pinker’s blood-soaked view of human origins. “Savages” are not nearly as savage as is often assumed.

The most puzzling part of the whole civilisation-to-the-rescue proposal is that whenever modern-day explorers have encountered preliterate people, the violent ones have invariably been the explorers. This was true when the British discovered Australia, when the Pilgrims landed in New England, and when Christopher Columbus came to the New World. Even when the indigenous people greeted the foreign visitors with gifts and friendship, the latter would usually just massacre their hosts. Columbus encountered people who didn’t even know what a sword was, only to marvel that with just 50 soldiers he could crush them. So much for civilisation’s edifying influence.

My own views focus on the natural abilities of primates to dampen conflict. Most of the time they are excellent at keeping the peace. I can’t believe that we are still bowing to Freud and Lorenz, not to mention Hobbes, while debating our evolutionary background. The idea that we can achieve optimal sociality only by subduing human biology is antiquated. It doesn’t fit with what we know about hunter-gatherers, other primates or modern neuroscience. It also promotes a sequential view – first we had human biology, then we got civilisation – whereas in reality the two have always gone hand-in-hand.

Civilisation is not some outside force: it is us. No humans ever existed without biology, nor any without culture. And why do we always consider our biology in the bleakest possible light? Have we turned nature into the bad guy so that we can look at ourselves as the good guy? Social life is very much part of our primate background, as are cooperation, bonding and empathy. This is because group living is our main survival strategy.

Primates are made to be social, made to care about one another and made to get along, and the same applies to us. Civilisation does all sorts of great things for us, but does so by co-opting natural abilities, not by inventing anything new. It works with what we have to offer, including an age-old capacity for peaceful coexistence.

This is an edited extract from Mama’s Last Hug: Animal Emotions and What They Teach Us About Ourselves by Frans de Waal, published by Granta on 14 March and available at guardianbookshop.co.uk

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