From early 1974 through most of 1976, a male chimpanzee named Yeroen held the position of alpha leader in the large, open-air chimpanzee colony at Burgers zoo in Arnhem in the Netherlands. His reign was roughly coterminous with the presidential administration of Gerald R Ford in the United States.

Yeroen became famous (among Homo sapiens) when the Dutch primatologist Frans de Waal showcased his leadership style in a classic 1982 book, Chimpanzee Politics. In their Machiavellian machinations and power games, De Waal argued, chimps turn out to be a lot like human beings.

The curious case of Donald Trump, however, now shows that human beings turn out to be a lot like chimps.

In the wild and in captivity, chimpanzee colonies organize themselves into tightly structured hierarchies. Power is vested in the biggest, strongest, and most outgoing males in the group, with the alpha male on top. The alpha leader dominates all others through tactics of threat, intimidation, bluffing, and outright aggression – and importantly, by forming short-term, pragmatic coalitions (let us call them “deals”) with other high-status males.

Chimpanzee politics can be intricate, but they always obey the rules of social dominance. Because chimps and humans evolved from a common ancestor going back 5-7m years, we humans know deep in our brains what social dominance is all about. Our expectation that social status can be seized through physical power and threat – that the strongest, biggest and boldest may indeed lord it over the rest of us – is very old, awesomely intuitive, and deeply ingrained.

Social psychologists today distinguish between the social dominance form of human leadership, on the one hand, and leadership through prestige on the other. Both are grounded in human evolution, but the prestige form is younger, tracing back a mere million years or so to the time when our hominid ancestors began to form culture. In the prestige paradigm, leaders attain their authority in the group by demonstrating culturally valued expertise – as, for example, in cooking, defending the tribe, healing, peacemaking, or (in the modern world) science, education, technology, the arts, business, law, medicine, communication, and so on.

For human beings today, dominance and prestige compete with each other as the two primal expressions of leadership.

When it comes to US presidents, we expect to see a bit of both.

For Trump, however, it is dominance all the way through.

An especially effective dominance mechanism for the alpha chimp is the charging display. The top male essentially goes berserk and starts screaming, hooting, and gesticulating wildly as he charges toward other males nearby. Pandemonium ensues as rival males cower in fear and females grab their little ones and run for cover.

Once the chaos ends, there is a period of peace and order, wherein rival males pay homage to the alpha, visiting him, grooming him, expressing various forms of submission.

Trump’s incendiary tweets are the human equivalent of a charging display. Designed to intimidate his foes and rally his submissive base, these verbal outbursts reinforce the president’s dominance by reminding everybody of his wrath and his force. When the alpha chimp charges, you cannot help but take note – with your ears and with your eyes.

Look at Mr Trump. What do you see? He is physically big and dynamic. His face gives the impression of a volcano about to explode. And explode he does, with regularity. Trump is more overtly aggressive than any political figure in the United States today, so aggressive, so insulting, so egregiously denigrating that you thought he might not be bluffing when, for example, he threatened to “lock Hillary up”, or when he warned North Korea that it “will be met with fire and fury like the world has never seen”.

Throughout primate evolution, bluffing appears prominently on every syllabus ever written for dominance psychology 101 (including The Art of the Deal). It was a standard tactic for Yeroen. But is Trump bluffing? What if he isn’t?

One of the most bizarre (and psychologically telling) events in the Trump administration so far was the president’s first full cabinet meeting, on 12 June 2017.

With the cameras rolling, each cabinet official in turn proclaimed how honored or blessed he (or she) was to serve the primal leader. The vice-president, Mike Pence, began the submission fest with these words: “Thank you, Mr President, and this is the greatest privilege of my life, to serve as vice-president to a president who is keeping his word to the American people and assembling a team that is bringing real change, real prosperity, and real strength back to our nation.”

And on it went, around the room, one obsequious gesture after another. Similarly, chimps show a wide range of deference displays in the presence of the alpha, including grooming, stroking, bowing, and other variations on the theme of sucking up.

In the prestige paradigm of leadership, the president’s cabinet would be viewed as a body of experts charged with running government agencies and providing the president with critical advice. But under the aegis of dominance, specific expertise is irrelevant. What matters instead is fealty to the alpha.

This is why Trump will never forgive the attorney general, Jeff Sessions, for recusing himself from investigations into charges that Russia meddled in the 2016 election. In a July interview, Trump described Sessions’ move as “very unfair to the president”.

And this is why various officials in the administration all now know what Sean Spicer learned early in his short tenure as White House press secretary: you may think you are speaking to the American people, but in reality there is an audience of one.

Even the biggest and most aggressive alpha chimp needs allies if he is going to hold on to power. Psychological research shows that among chimps and humans, socially dominant leaders are especially inclined to form short-term contractual relationships that are grounded in pragmatics rather than principle – temporary deals that work today, but may be gone tomorrow: “You may be a horrible person, but if you work with me on Task A today, I will work with you on Task B tomorrow. By Friday, we may be opponents on some other deal, we may even be trying to kill each other off, but hey, Friday is way in the future, and chimps do not project their leadership programs too far into the future.”

Nor does Trump, it seems. Many observers have remarked upon his short-term, contractual approach to international relations and to negotiating with Congress. “He’ll promise you the world,” said Jeremy Shapiro, a former state department official. “And 48 hours later, he’ll betray you without a thought. He won’t even know that he’ll be betraying you.”

The alpha chimp’s focus on temporary arrangements designed to serve immediate goals brings us to the hollow core of Trump’s personality. In a psychological profile I wrote in early 2016, when he was a candidate, I remarked that it is very difficult to discern a moral narrative in Trump’s head about how he came to be the person he is becoming. To the extent there is a narrative there, it is something vague about fighting to win.

Psychological research suggests that constructing a self-defining story about who you are, were, and will be is a signal psychological task of adulthood. Nearly every leader, moreover, draws upon his or her internalized self-narrative for moral and strategic guidance, and to inspire those whom the leader leads.

As different as they were in their approaches to leadership, both Barack Obama and George W Bush created highly redemptive stories – narratives of suffering and hope – to make sense of their lives. Those stories informed their presidencies, for better and for worse.

By his own admission,Trump is not an especially introspective person. Nor is he retrospective or prospective. There is very little by way of a narrative arc to Trump’s consciousness. Instead, he lives in the angry contractual moment, moment to moment, deal-making scene to deal-making scene, episodic – more like an episode of Seinfeld than a feature-length movie.

The goal for each moment is to win the moment. And that is it. There is no storyline beyond winning the moment. There is no overarching moral narrative of atonement or liberation or progress. There is no valued end state toward which you and the people you lead strive in the long term, no envisioned end to the story in which Americans enjoy greater freedom, equality, or happiness.

Almost 40 years ago, in an interview with People magazine, Trump said: “Man is the most vicious of all animals, and life is a series of battles ending in victory or defeat.” His philosophical musing on human nature applies even better to life in a chimpanzee colony. The alpha chimp survives each angry moment to win the next battle – until his winning streak ends.

Dan P McAdams is the Henry Wade Rogers professor of psychology at Northwestern University. He is the author of The Art and Science of Personality Development and the author of the recent paper The Appeal of the Primal Leader: Human Evolution and Donald J Trump