When the Chimpanzee Awakens in Us: How Fear Rewires Humanity

Why do some societies become aggressive while others remain peaceful? Why do crises give rise to populism, while security fosters altruism? 

This article explores how biology, genes, and environment shape mass human behavior — from primates to parliaments.

Despite all technological and cultural achievements, Homo sapiens remains a biological species governed by a set of evolutionary behavioral strategies. Our emotions and actions — from the highest empathy and love to terrifying cruelty and hatred — have evolved over millions of years and reflect the dual nature of the human species (CovalentBond). We often marvel at our own contradictions, calling the most atrocious acts “inhuman,” when in fact they are all too human — deeply rooted in our biological inheritance. The task of science is to explain how this duality manifests and what drives it.

Ethologists and anthropologists have long observed that primate behavior — our closest evolutionary relatives — holds a key to understanding human nature. For example, two species of chimpanzees, the common chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus), show a striking contrast. Common chimps live in patriarchal groups, often display aggression toward outsiders, and maintain a rigid hierarchy dominated by alpha males. Over ~50 years of observation, 152 intra-species killings have been documented in 15 different chimp communities, mostly perpetrated by males. Bonobos, by contrast, are matriarchal “pacifists”: in the same time frame, only one suspected killing has been recorded among them. Their groups are led by females, conflicts are soothed with frequent sexual interactions, and encounters with neighboring groups often resemble unifying celebrations — including group-wide sexual encounters among strangers (Friends of Bonobos) (Friends of Bonobos). Bonobos are famously described as “the affectionate primates” who use touch and sex as natural tools to release social tension and anxiety. As a result, bonobos exhibit the most peaceful behavioral strategy among primates — more peaceful even than most human societies.

It is essential to emphasize that the environment plays a crucial role in determining which behavioral scenario prevails. Bonobos are believed to have evolved in an ecosystem rich in resources and free from competition with gorillas in the southern Congo. This helped shape a cooperative, sexually open matriarchal society. In contrast, chimpanzees lived under harsher conditions with fierce competition for food and territory, which fostered a more aggressive, patriarchal social structure. In other words, when the environment is safe and abundant, social animals tend to display greater tolerance and altruism; under conditions of scarcity and threat, aggression and rigid hierarchy become more pronounced. Humans are no exception: in stable, well-protected societies, we observe more trust, generosity, and tolerance, while anxiety and instability give rise to suspicion, a desire for “a strong hand,” and rigid in-group/out-group thinking. Research confirms that under perceived social threat, people become more inclined to adopt authoritarian beliefs as a means of feeling secure (Te Herenga Waka-Victoria University of Wellington). Put simply, when humanity is “frightened,” our chimpanzee-like traits come to the fore — aggression, group selfishness, a hunger for dominance. When we are calm, well-fed, and confident about tomorrow, our bonobo-like qualities emerge — empathy, cooperation, sexual and cultural freedom.

The Genetics of Behavior: Short and Long Alleles of Fear and Trust

Biological differences in behavior — whether in humans or other primates — are largely influenced by genetic variation. Modern social neurobiology and behavioral genetics have identified genes associated with anxiety levels, aggression, empathy, and sociability. One of the most studied is the 5-HTTLPR polymorphism in the promoter region of the serotonin transporter gene (SERT). It exists in two primary forms: the “short” (S) and the “long” (L) allele. Serotonin is a neurotransmitter that regulates mood and anxiety, so it’s no surprise that the SERT gene affects emotional stability.

Meta-analyses reveal clear sex differences in how this gene functions. Among women, the short allele is associated with heightened anxiety, depressive tendencies, and other “internalizing” responses. Simply put, female carriers of the S-allele are more prone to stress and have a higher risk of depression and anxiety disorders under adverse conditions. In men, however, the same short allele behaves differently: according to several reviews, in males the S-genotype correlates with increased aggression, deviant behavior, and more “externalizing” stress responses. In other words, the short 5-HTTLPR allele in men is linked to higher aggression and behavioral disorders, while in women — to anxiety and depression. Additionally, adverse life events amplify these effects in both sexes. These differences become particularly pronounced during adolescence and tend to level out in older age, suggesting a hormonal influence. Thus, a single genetic variant can influence male and female behavior in opposite ways, reinforcing gender-typical reactive strategies — aggression versus anxiety.

Beyond serotonin transport, neuropeptide systems play a vital role — especially oxytocin and vasopressin, which regulate social bonding and attachment. The OXTR gene (oxytocin receptor) also displays polymorphisms in the form of “long” and “short” alleles. Oxytocin is often referred to as the hormone of trust and attachment, and studies confirm that individuals with the long OXTR allele tend to be more trusting, empathetic, and prosocial than carriers of the short variant. Those with the “long” allele are better at recognizing others’ emotions and are more inclined to cooperate. Moreover, the long allele offers a degree of resilience against childhood stress — individuals with this variant are less likely to develop aggressive or antisocial behavior in adulthood even if they experienced early trauma. In contrast, the short OXTR allele is associated with lower empathy and openness, and most notably, increased vulnerability to adverse environments. Children with the short allele who grow up in dysfunctional settings are significantly more likely to show violent or antisocial behavior later in life. These findings support the differential susceptibility hypothesis: carriers of the “favorable” (long) variants benefit more from positive environments but may also suffer more in harmful ones, while “unfavorable” (short) alleles provide less responsiveness to support but greater sensitivity to threat (CovalentBond). One experiment, for instance, showed that individuals with the GG genotype of OXTR (two long alleles) were particularly responsive to social support — it greatly reduced their stress. In contrast, those carrying the A allele (short variant) showed lower stress resilience even with support (CovalentBond). These A-carriers also tend to exhibit stronger emotional reactivity under social pressure, sometimes accompanied by bursts of aggression. But the key takeaway is that OXTR does not encode “aggression” or “kindness” directly — it influences one’s tendency toward conflict indirectly, through empathy, trust, and stress response.

A similar role is played by the vasopressin system, which is key to social dominance and monogamous bonding. Among primates, a polymorphism in the AVPR1A gene (vasopressin receptor) has been linked to variations in social behavior. In western chimpanzees, the long allele of AVPR1A is associated with what researchers call a “smart social” behavioral style — the ability to cooperate while also asserting dominance through flexible leadership. Interestingly, in male chimpanzees the long variant often leads to more pronounced alpha-type behavior (dominance, impulsivity), whereas in females the same genotype results in more beta-style leadership — modest, cooperative, and consensus-oriented. This mirrors the sex-dependent effects observed with 5-HTTLPR: the impact of the gene depends on biological sex. In humans, AVPR1A polymorphisms also influence sociability. A meta-review of 27 studies showed that variations in AVPR1A and OXTR genes significantly contribute to differences in social behavior. For vasopressin specifically, carriers of the long allele tend to be more altruistic and generous, but at the same time more cautious in situations requiring trust — they are less willing to cooperate if deception is possible. In contrast, short-allele carriers are more likely to trust strangers and reciprocate in cooperative interactions. This matches findings on OXTR and aligns with an experiment in which men with the SS genotype for the AVPR1A microsatellite RS3 (i.e. short alleles) gave more money to their partners in trust games and returned a larger share as trustees — indicating that the short variant is linked to higher trust and reciprocity. At first glance, this may seem paradoxical — a “disadvantaged” allele fostering more trust — but it fits the evolutionary logic of balancing social styles: short alleles may promote group cohesion through interpersonal trust, while long alleles provide healthy skepticism and leadership capacity.

In humans, there is still no definitive proof that the long AVPR1A allele increases dominance (as seen in chimpanzees), but indirect evidence does exist. Due to their lower trust and higher vigilance, carriers of the long variant may be more likely to display an aggressive-dominant communication style, often focused on defending against potential exploitation. Moreover, the long vasopressin receptor alleles have been linked to the strength of romantic bonds. Paradoxically, in men these variants correlate with difficulties maintaining monogamous attachment — a greater tendency toward infidelity or challenges in sustaining long-term emotional closeness. This is not a “cheating gene,” but it does suggest that the vasopressin system influences human romantic behavior in complex ways.

Geneticists also point out cultural and geographic differences: the frequencies of “social” alleles are unevenly distributed across global populations. For instance, the G allele of the oxytocin receptor (the “long” version) is most prevalent in Africa and least common in East Asia. The possibility that such differences partially shape cultural patterns is an open subject of discussion. One hypothesis suggests that populations with more “trusting” alleles tend to develop more cooperative and emotionally expressive cultures, while those with a higher prevalence of “cautious” alleles may form more reserved and conservative social norms. These are cautious assumptions, of course — actual societal behavior arises from a wide array of factors, and genetics is just one component. Still, modern research increasingly confirms that biology does affect social structures, albeit indirectly. People with different genotypes vary in empathy, anxiety, and aggression levels — and thus respond differently to changes in the external environment. And when that environment changes for everyone, a massive social game of genotypes begins: some panic and seek protection, others grow aggressive, while some maintain altruism — and the ones who end up playing a decisive role ultimately shape the face of society.

From Genes to Government: How Personal Reactions Become Collective Shifts

Individual differences in anxiety, empathy, and aggression shape not only a person’s character but also the behavior of social groups. When a population has a higher proportion of individuals genetically predisposed to stress sensitivity, the overall societal response to perceived threats becomes heightened. Even people who are naturally more resilient begin to mirror dominant moods — a phenomenon driven by mechanisms of social contagion.

Mass behavior is not separate from biology — it is a product of it. When most people feel anxious, the demand for a “strong hand” rises. When empathetic, confident individuals dominate, society leans toward solidarity and tolerance. Thus, genes do not govern politics directly, but they influence how a society reacts to stressors.

This shift from individual biology to collective psychology is key to understanding modern political processes. And to see how this works in practice, one only needs to look at countries where periods of widespread anxiety have transformed fundamental values, attitudes, and behavioral norms.

Stress, Attachment, and the Craving for Control: How Environment Shapes Society

How exactly does the socio-political environment activate our deeper behavioral mechanisms? Research in mass psychology and attachment theory shows that the feeling of basic safety plays a central role. Decades ago, John Bowlby, the founder of attachment theory, described how children who experience reliable care in early life — a secure base — tend to grow up more confident and open to the world. Those who lack such a foundation become more anxious, suspicious, and prone to seeking security in external authority. These patterns persist into adulthood and play out in mass politics. When external conditions are stable, people are more likely to trust each other, to be tolerant of outsiders, and to value freedom. But during upheavals — wars, economic downturns, spikes in crime — there’s a growing societal demand for order, control, and “strict discipline.” This reflects an evolutionary mechanism: in the face of existential threats, our ancestors rallied around strong leaders and expelled outsiders; in peaceful times, they could afford greater diversity and personal freedom.

Modern experiments confirm that perceived threat directly increases authoritarian attitudes. Even brief exposure to a sense of danger makes people more likely to agree with statements like, “In difficult times, we need one strong leader or party to rule” (Te Herenga Waka-Victoria University of Wellington). Following terrorist attacks, natural disasters, or — as we’ve recently seen — pandemics, surveys show a rising share of citizens willing to restrict rights in the name of security and to support more conservative, even xenophobic, political forces (Nature) (Nature). Psychologists call this an “authoritarian response.” But it’s important to note: not everyone reacts the same way. What gets triggered is an existing predisposition, a kind of “dormant” potential for aggressive or anxious behavior — the very tendencies described earlier. For example, political psychologist Karen Stenner identified about one-third of the population as prone to latent authoritarianism: these individuals may appear perfectly ordinary in peaceful times, but once they feel threatened, their views shift rapidly toward a desire for rigid order and intolerance of “outsiders.” Others, by contrast — those with higher anxiety thresholds or greater empathy — maintain liberal values even under pressure. Interestingly, this roughly mirrors the distribution of genetic types. Among chimpanzees, about 60–80% carry the “short” variant of certain genes that do not promote leadership potential, while 20–40% possess the “long” variant, associated with dominance. In Solomon Asch’s famous conformity experiment, 75% of participants succumbed to group pressure at least once, while about 25% maintained independent judgment (CovalentBond). It appears that nature has “wired” roughly a quarter of us with the capacity not to follow the crowd, but to lead it — whether toward good or evil.

What happens when external circumstances suddenly shift? Societies begin to reframe their norms — a process often described as a movement of the Overton Window in collective consciousness. What seemed radical yesterday can feel justified today in a climate of fear. If the majority once resembled peaceful bonobos, fear can swiftly turn many into aggressive chimpanzees. This transformation becomes especially pronounced when the signals come from leaders or cultural role models. People tend to imitate — if elites display intolerance or selfishness, the public follows. Conversely, calm leadership can help extinguish panic. Psychology refers to this as emotional contagion and social learning: behaviors, fears, and values spread not just through argument, but through example.

Political Shifts in an Anxious World: From Germany to Japan

In recent years, we’ve witnessed in many countries the very “drift toward aggressive strategies” mentioned earlier. Rising economic uncertainty, geopolitical tensions (wars, terrorism), and global epidemics create a climate of anxiety — one that reshapes mass sentiment. And the evidence is everywhere.

Take Germany, long seen as a stronghold of liberal democracy. The country has experienced an unprecedented surge in far-right support. The Alternative for Germany (AfD) party, considered fringe just a decade ago, now consistently ranks among the top three political forces. Even more striking: in autumn 2024, AfD won a regional parliamentary election for the first time since World War II — in the state of Thuringia. AfD is particularly popular among young voters: surveys show that up to 22% of Germans under 30 are ready to vote for the far-right. What drives these young voters into the arms of radicalism? Research — and AfD supporters themselves — point to fear and frustration. “Germans are afraid of becoming strangers in their own country,” explained one young AfD candidate (Euronews). Merkel’s open-border policy, the influx of refugees, rising crime rates, and a perceived loss of national identity all feed into that anxiety — which then transforms into support for ultranationalist ideas (Euronews) (Euronews). Slogans like “Be proud to be German again” resonate with those who feel that their traditions are under threat. Thus, cultural fear — of migrants, of globalization — has turned part of a once pacifist postwar society into a radicalized group demanding closed borders and a firm hand.

France is experiencing a similar trend — where migration and security have become central political issues. Historically, France has upheld strong republican values of equality, but waves of refugees from Africa and the Middle East, along with a series of terrorist attacks, have pushed public opinion steadily to the right. In autumn 2023, the French parliament — with support from both President Emmanuel Macron’s government and the opposition — passed the most restrictive immigration package in 40 years. The new law introduces annual immigration quotas, requires foreign students to pay deposits for the full duration of their studies, tightens eligibility for benefits, and streamlines deportation procedures for undocumented migrants. French human rights advocates called the measures “the most reactionary in recent decades.” Macron, who came to power as a centrist liberal, was forced to yield to right-wing pressure and significantly toughen immigration policy. This serves as a vivid example of how even political elites who once championed humanist values are shifting course under the weight of public anxiety. The rise in popularity of Marine Le Pen and her National Rally movement also illustrates that many French citizens have grown disillusioned with the ideals of openness and now demand protection from change. Topics that were recently taboo — such as strict migrant controls, welfare cuts, and harsher asylum conditions — are now debated as part of the new normal. While France still has strong opposition to such measures (evident in protests against the “Darmanin Law” in Paris), the very passage of these laws signals a serious shift in public consensus — where security now takes precedence over individual rights.

In Eastern Europe, similar processes are unfolding with their own regional characteristics. In Romania, amid economic struggles and corruption scandals, national-populist rhetoric has surged. In 2025, the country narrowly avoided electing a far-right president: George Simion, the leader of the AUR party and an open admirer of Donald Trump, won the first round of the presidential election with 41% of the vote, securing majorities in most counties — especially in rural areas and among voters disillusioned with the liberal elite. His image as “the simple guy against the establishment” and his nationalist slogans appealed to those who feel abandoned by urban political elites. Only in the second round did a moderate, pro-European candidate manage to win — but the message was clear: a significant portion of Romanian society is ready to vote for a “strong hand” that stands against the EU, against migrants, and for traditional values. In neighboring Moldova, the battle between fear and hope is even more intense. Since 2022, the country has been rocked by prolonged pro-Russian protests: thousands of people took to the streets against the pro-European government, blaming it for soaring prices of gas, electricity, and food (BBC). These protests were orchestrated by the Shor Party, an oligarch-backed opposition group openly supported by Moscow. People whose utility bills consumed 70% of their income were desperate — and became easy targets for pro-Russian propaganda promising “stability at any cost” (BBC) (BBC). President Maia Sandu warned of Russia’s attempt to destabilize the country by amplifying fear. Ultimately, the government regained control: in June 2023, the Constitutional Court banned the Shor Party as an unconstitutional organization, citing its coordinated efforts to undermine society and derail the European course (Reuters). Yet the public mood remained fragile: many Moldovans still long for “simple solutions” — whether through a pro-Russian comeback or a new “strong leader” who promises to lower prices and restore stability. Moldova stands as a vivid example of how external war (in Ukraine) and internal economic shocks can make a society vulnerable to division and populism.

Even countries far from Europe are feeling the global shift. Japan, which for decades adhered to pacifist principles, is now undergoing unprecedented change under the pressure of a changing security environment. Threats from North Korea and an increasingly assertive China have led many Japanese citizens to question their long-standing strategy. Prime Minister Fumio Kishida’s government has announced a sharp military buildup: Japan plans to double its defense budget to 2% of GDP (around $315 billion over five years), which would make it the third-largest military spender in the world (LE MONDE diplomatique). This marks a dramatic departure from postwar pacifism. The Japan Self-Defense Forces will now be authorized not only to defend domestic territory but also to launch preemptive strikes against enemy bases if a threat is imminent (LE MONDE diplomatique) (LE MONDE diplomatique). In essence, Japan is adapting to a new reality — one in which relying solely on the diplomatic “umbrella” of the United States is no longer seen as sufficient. A society that until recently protested against any militarist steps is now gradually embracing this shift — driven by the perception of real danger. Notably, these debates intensified after the war in Ukraine and Russia’s aggression, which showed the Japanese public that peace treaties can be broken — and that “trust in diplomacy must be backed by readiness.” While Japan still has a vocal movement defending its pacifist constitution (especially Article 9), public sentiment is shifting: more and more citizens now believe that the country needs a strong military, even at the cost of abandoning long-standing ideals LE MONDE diplomatique) (LE MONDE diplomatique). The fear of war is now rewriting Japan’s social contract, in a nation where that contract once seemed unshakable.

These examples represent only part of a broader global pattern. In the United States, the United Kingdom, Brazil, Turkey — everywhere, we can trace how periods of upheaval trigger conservative and authoritarian trends. But at the same time, there are counterforces at work: in the very same societies, “micro-communities” emerge that strive to uphold liberal and humanist values — like “bonobo islands” amidst the noise.

As your obedient servant noted in the study "Peaceful People", in the most developed democracies, there exists a segment of the population that essentially lives according to a bonobo model: they are tolerant of different opinions and lifestyles, support freedom of expression and equality — and statistically, they report the highest levels of personal happiness. Yet these people are scattered thinly across the population and often politically passive, while more aggressive groups tend to organize quickly and make themselves heard. As a result, the voice of the peaceful minority is often drowned out by the chorus of fear and calls for simplistic solutions.

Pragmatism Over Principles: Is This the New Global Normal?

The role of major powers — those setting global norms — deserves particular attention. In the previous century, the United States and many European countries often professed commitment to human rights and humanitarian ideals (even if selectively). But today, we’re witnessing a visible shift toward pragmatism and realpolitik. “We’ve returned to a world best explained by realism — where great powers compete for influence, and the rest adapt as best they can,” political scientist Stephen Walt observed after the start of the Ukraine war (The International Spectator). This statement captures the spirit of our time. Russia’s full-scale invasion, the sharp escalation of US-China rivalry — all of this has brought back the logic of power politics, leaving ideals behind. Even democratic leaders now increasingly speak the language of geopolitical interests, rather than global moral obligations.

The war in Ukraine is a clear illustration of how pragmatism often overtakes humanitarian concerns at the level of statecraft. On the one hand, the West has helped Ukraine resist — through weapons, sanctions, and symbolic solidarity — demonstrating a kind of democratic alliance in action (The International Spectator) (The International Spectator). But on the other hand, that support has been carefully calibrated: Ukraine receives just enough to avoid losing, but not enough to decisively defeat Russia and risk drawing NATO into direct conflict. The West avoids offering “too effective” assistance — fearing nuclear escalation or economic backlash. In this strategic calculation, the lives of Ukrainians become a bargaining chip. The priority is not always humanitarian protection — but rather containing Russia and sending signals to China. Some critics have called this a “war to the last Ukrainian”, noting how moral rhetoric often takes a back seat to cold calculus. Of course, Western leaders still speak the language of freedom and values — but their actions are often guided by strategic interests. For example, when the global energy market faced a crisis in 2022–23, European democracies swiftly signed deals with authoritarian regimes like Saudi Arabia and Qatar for oil and gas, despite having previously condemned them for human rights abuses. The principle that “realpolitik takes precedence over moral values” is becoming increasingly evident — both in rhetoric and in action.

This growing preference for realpolitik over moral principles sends a message to the rest of the world: double standards are acceptable, and national interest trumps idealism. If the West, long the self-proclaimed teacher of democracy, now openly cooperates with dictators and wages proxy wars, why shouldn’t others do the same? This erosion of commitment to universal human values is becoming the “new normal.” At the UN and other global forums, we increasingly hear: “Let’s stop pretending. Every nation for itself.” This is a dangerous shift. It’s already being felt by ordinary people in conflict zones — from Syria and Yemen to Ukraine. When powerful actors bypass humanitarian norms in pursuit of advantage, it is civilians who pay the price.

Yet through the lens of science, this global hardening is not unexpected. It reflects the cyclical behavior of Homo sapiens. When the dominant force in a global system (e.g., the U.S.) shifts from idealism to pragmatism, it signals internal change: a society weary of moral burden, divided in opinion, and increasingly fearful of the cost of global leadership. The Trump era exposed America’s instinct for isolationism, deal-making, and admiration for autocrats. Humanitarian programs were slashed. “America First” became a doctrine. Even under Biden, although value-based rhetoric returned, the deeper trend persists: America no longer wants to carry the moral torch for free. As researchers note, after the idealism of the 1990s, we are witnessing the revenge of realism — where great powers operate within spheres of influence, not by universal ideals (The International Spectator) (The International Spectator). To many countries, this offers permission to pursue their own strategic egos. Where once a violator of international norms might be expelled from the “club of civilized nations,” today those clubs barely exist — replaced by interest-based alliances.

Does this mean we’re doomed to a new era of global aggression? History suggests that the pendulum swings: after realism comes reckoning — sometimes at the cost of catastrophe. Perhaps, after witnessing the horrors of war and authoritarianism, a new generation will once again seek meaning and values. The nature of Homo sapiens is dual. Within us, there is always a struggle — between chimpanzee and bonobo. But awareness of this nature is already part of the solution. If we understand that aggression grows from fear, and fear from perceived threat, then smart policy can work to reduce that fear — by strengthening social safety nets, combating inequality, and choosing diplomacy over militarization. Epigenetic studies show that traumatic experiences can reprogram gene expression, passing cycles of violence to future generations. But the reverse is also true: long-term peace and wellbeing can dampen warrior traits — effectively “domesticating” aggression, as wolves were once domesticated into dogs. Some scientists even compare bonobo and human evolution to a kind of self-domestication: selection against aggression may have played a key role in shaping more empathetic beings (eScienceCommons, Emory University).

In conclusion, let us return to the metaphor of Peaceful People. Bonobos are a living example of a primate society without tyranny or war — a kind of natural utopia, where conflicts dissolve through intimacy and friendliness. The author of the original study rightly calls bonobos a glimpse of an alternative reality that did come true. Humans are, of course, far more complex. But the message holds: we are not aliens — we are nature’s children. And our darkest and brightest traits alike emerge from our evolutionary past. Understanding this gives us a clearer lens through which to view social change. When societies grow more aggressive, authoritarian, or hateful, it is not a collective madness — but an activation of deep evolutionary programs under environmental pressure. By recognizing these patterns, humanity can choose — if it wants to — to change the environment so that our better selves prevail. This is an interdisciplinary task — for neurobiologists, geneticists, sociologists, and practical policymakers alike.

Today, unfortunately, the world seems to be moving from utopia to dystopia: “The idea of cultural assimilation under a banner of peace has failed…”, as the Peaceful People article bitterly states. The world is fragmenting, and within every nation, micro-chimpanzees and micro-bonobos — people with opposite values and worldviews — are finding it harder to understand one another. But evolution is not fate. Homo sapiens has consciousness and culture — tools that can soften the tyranny of genes. Perhaps, acknowledging our animal instincts is the first step toward not blindly obeying them. Because peaceful people are not a utopia — they are a part of us. Our task is to give that part a chance to become the new norm.

This article draws on the original research “Peaceful People” by Mikhail K., published on CovalentBond, as well as current scientific studies in primatology, genetics, and behavioral sociology. These insights help connect the biological foundations of human behavior with their social expressions, offering an explanation for the shifts in collective conduct that occur when environmental conditions change — from molecules to global powers.