The macaques come down from the trees at Padangtegal when the first tour buses reach Ubud. Agustín Fuentes (b. July 30, 1966) sits against the temple wall in the shade, a notebook on his knee, and watches them work the crowd. A bus driver waits in the same shade a few feet off. So do the monkeys. The driver does not shoo them. They leave his side mirrors alone, he tells Fuentes, and so man and macaque keep an easy peace through the slow hours. “We both wait together,” the driver says. A young guide at a second temple says it the same way. Man and monkey both wait for the tourists. When the tourists come, both go to work.
Fuentes has spent a career on scenes like that one. A primate sits beside a man, shares his shade and his living, and the line between the animal world and the human world will not hold still. He tells interviewers that the field keeps humbling him. He watches monkeys do something he had filed under human, and he catches himself. The behavior turns out older than people.
That small forest in Bali holds his argument. Humans are primates who build worlds with other creatures and with each other, and who cannot be read from their genes alone.
He was born in Santa Barbara in 1966. His father, Víctor Fuentes, left Madrid after the Spanish Civil War and became a scholar of Spanish literature in California. The house ran on books in two languages and on a respect for both the sciences and the humanities, and the son carried both into his work.
He went to Berkeley and took a double bachelor’s in zoology and anthropology in 1989, a master’s in 1992, and a doctorate in anthropology in 1994. His adviser was the primatologist Phyllis Dolhinow (1933-2019). She had trained under Sherwood Washburn (1911-2000), the man who pulled physical anthropology away from its nineteenth-century habit of sorting humans into racial types and turned it toward evolution, genetics, ecology, and the behavior of living primates. Fuentes took that inheritance and pushed it further. Biology by itself could not explain a human being, he argued, and neither could culture by itself. You needed both at once.
His first long fieldwork ran in the Mentawai Islands of Indonesia in the late 1990s, where he followed langurs and pig-tailed monkeys and tracked how they grouped, mated, and made peace after a fight. Then he turned to macaques, the most adaptable monkeys on earth and, after humans, the most successful primates at spreading across the planet. He worked the Barbary macaques of Gibraltar, the long-tailed macaques of Bali and Singapore, the temple monkeys that live off tourists and offerings.
He could not study these animals as if people were not there. People were the point. Tourists fed them. Temples housed them. Farmers fought them. Diseases passed back and forth across the contact zone, monkey to man and man to monkey. Out of this came the field he helped found with the anthropologist Leslie Sponsel: ethnoprimatology, the study of how humans and other primates shape each other’s lives where they live side by side. Most primatologists of an older school had treated human presence as contamination, a thumb on the scale. Fuentes treated it as the subject.
The work put him between disciplines, and he liked it there. He told the president of the American Anthropological Association that he saw himself first as an anthropologist who happened to carry biological training, and that he thought he might be the first biological anthropologist to publish in the flagship journal of the cultural side of the field. Bones and genes sat on one side of the old divide, meaning and culture on the other. He kept walking back and forth across it.
By the 2000s he had set himself the largest question in his field. What makes humans human? He rejected the usual answers. Raw intelligence, aggression, a killer instinct sharpened on the savanna: he set all of them aside. His answer was imagination joined to cooperation. Humans picture things that do not exist, then work together to bring them into being. From that single power he traced tools, language, art, religion, law, and science.
He made the case at book length in The Creative Spark in 2017, drawing on fossils, stone tools, genetics, and brain science. A child’s finger painting and a Pleistocene hand axe come from the same source, he argued, the power to imagine a possibility and try to build it. He pressed the cooperation point against a long tradition that put violence at the center of the human story. The fossil and archaeological record, he said, shows people sharing food, raising children together, and passing knowledge across generations long before it shows organized war. Hard and shifting environments rewarded flexible cooperation more than constant conflict.
In 2018 he gave the Gifford Lectures at the University of Aberdeen, the old Scottish platform for large arguments about science and religion. Those lectures became Why We Believe in 2019. Religion and morality, he argued there, are not errors or accidents of a clever brain. They grow from the same evolved capacity for shared belief that lets large groups of strangers trust one another, keep promises, and build institutions. He set this inside a wider movement in biology, the extended evolutionary synthesis, which holds that organisms do not only adapt to their environments. They remake them, and so change the pressures their descendants will meet. Human culture and technology, on this view, are evolutionary forces in their own right.
Fuentes also built a career on attacking ideas he judged false and harmful. In Race, Monogamy, and Other Lies They Told You in 2012, he went after three popular beliefs: that humans divide into biological races, that humans are aggressive by nature, and that men and women are wired as opposites. Race, he argued, is not a sound biological division of the species, and many habits people call natural are history and custom in disguise.
This work made him a public figure, and it drew fire. The sharpest fight came in 2021. Science ran his short editorial on the 150th anniversary of Darwin’s The Descent of Man. Fuentes praised the book as a text to learn from, then spent most of his space on its racism and sexism, and wrote that students should meet Charles Darwin (1809-1882) as a man whose prejudices warped his reading of the evidence.
The reaction was loud. The evolutionary geneticist Brian Charlesworth and the historian of science Robert J. Richards published rebuttals. Jerry Coyne went after the piece on his blog across a run of posts. The writer Robert Wright pushed back in public and asked Fuentes, on Twitter, to produce the lines where Darwin justified empire and genocide. Fuentes pointed him to a chapter. Wright pulled his own copy down, read it, and reported that he found Darwin explaining how one group displaces another without endorsing it. The critics shared one charge. Fuentes was judging a Victorian by present morals and handing ammunition to people who reject evolution. Fuentes and his defenders answered that a great scientist’s prejudices belong in the record, and that shielding Darwin from criticism turns him into a saint rather than a man.
His 2025 book carried him into the hottest argument of the moment. Sex Is a Spectrum opens with the bluehead wrasse, a reef fish that starts life producing eggs and can later turn into the breeding male of its group. From there Fuentes argues that the biology of sex runs wider than two tidy boxes, that chromosomes and hormones and anatomy do not always line up, and that a model built on distributions and overlap fits the evidence better than one built on a clean pair of types.
The book split its readers along the lines you might guess. Psychology Today and The Gay and Lesbian Review praised it as careful and overdue. Critics came down hard. The philosopher Tomas Bogardus, writing on Colin Wright‘s Substack, and the biologist Jerry Coyne argued that Fuentes had shown either nothing or the reverse of his title, since biological sex rests on two gamete types, the large egg and the small sperm, and admits no third. The anthropologist Edward Hagen faulted the book for cataloguing variation while skipping the explanations. Fuentes tried to hold a careful line. On a podcast in June 2025 he said he was not claiming more than two sexes. Male and female are real, he said, but they are “typical clusters of variation” with wide spread inside each, not sealed and opposite kinds. His critics answered that this restates the binary or dodges it.
Through all of it the throughline holds. Fuentes joined Princeton in 2020 as a professor of anthropology. The American Academy of Arts and Sciences elected him that year, and his field gave him its first award for public outreach. He carries the title of National Geographic Explorer and writes for general readers as readily as for journals. He sits on the Rising Star team studying Homo naledi, the small-brained human relative from a South African cave that may have handled its dead, a find that scrambles the old link between brain size and complex behavior.
His message has not changed since the temple wall in Bali. A human being is an animal that imagines, cooperates, and believes, and that remakes the world it lives in and itself along with it. You cannot reach the bottom of such a creature through biology alone or culture alone. You have to sit in the shade and watch, and wait, and notice when the thing you took for human turns out to belong to the long line of primates that made you.
Fuentes and the Migration of Essences
Essentialism is a bet about words. The bet says a category name cuts nature at a joint, that the members of a kind share a hidden property that makes them what they are and accounts for the rest. Call something a tiger and you have named a an essence behind the noun. Stephen Turner (b. March 1, 1951) has spent a career refusing that bet for the categories social science loves. He is a nominalist. He treats “society,” “culture,” and “the social” as abstractions that people mistake for things. The names are heuristics. The explaining gets done by particular causes among particular people, not by an essence sitting behind the word. The recurring error, in Turner’s telling, is reification. You take a useful abstraction, grant it a nature, and then the nature seems to explain what the people themselves were doing all along.
By the letter of that complaint, Agustín Fuentes is Turner’s ally. Fuentes built his public career on dissolving essences. Race is not a biological kind. Sex sorts into “typical clusters of variation” rather than two essential, opposite types. Human nature comes in the plural, “human nature(s),” when he writes it at all. A man who says these things has signed the nominalist creed.
So the frame looks idle here. It is not. Essentialism is not a doctrine a man holds once and for good. It is a habit, and habits travel. The Turner question is not whether Fuentes believes in essences. He says he does not. The question is where he keeps the ones his work needs.
Start with sex. Turner’s nominalism carries one sharp tool: separate the property that defines a kind from the cluster of traits that travel with it. Sex as a gamete role is a defining property. It takes two values, the large egg and the small sperm, and there is no third. Around that property sit clusters of correlated traits, chromosomes and hormones and anatomy and behavior, and those clusters run wide and ragged and full of overlap. Fuentes is good on the clusters. Sex Is a Spectrum catalogs the variation with care. Then he reads variation in the clusters as variation in the kind, and the title follows. His own phrase gives the game away. A cluster is typical of something. The something it is typical of is the kind that sorts it. Spread inside a cluster does not melt the property that makes the cluster a cluster of one sex and not the other. Turner’s tool finds Fuentes nominalist about the traits and realist nowhere, which leaves the kind unaccounted for.
Be fair to the reply. Fuentes can say that “sex,” in speech and law and lived life, means the body and its traits, not the gamete, and that pinning the word to gametes is a choice he declines to make. Fair enough. But choosing which property defines the kind is the whole task, and you do not win it by pointing at the spread in the other properties. The critics who press the gamete point, the biologist Jerry Coyne and the philosopher Tomas Bogardus among them, are making a natural-kind claim, not airing a prejudice. The frame does not say they are right about everything. It says the argument turns on which property defines the kind, and that a catalogue of variation leaves that argument standing.
Race shows a different move. Fuentes dissolves biological race. Then he says race is real “socially.” Here the nominalist grows wary, because “the social” is the last place Turner lets an essence hide. Strip a kind of its biological essence and you have not earned a social essence to put in its place. You have a set of classifications and practices that particular people carry out, with real effects. Fuentes tends to speak of race as a thing with social reality and causal force, which puts back at the level of society the reified object he removed at the level of the genes. The anti-essentialist about DNA turns essentialist about “the social.” His reply is strong. The effects are real, the discrimination and the health gaps are measurable, so race is real in its consequences. The effects are real. The frame only holds that the consequences flow from practices and classifications among people, not from an essence named race, and that the noun is shorthand for the practices and not a thing behind them.
The deepest case is the one Fuentes treats as his contribution. He denies a fixed human nature. He writes the word plural to keep it from hardening. And then his whole positive program answers an essentialist question. What makes humans human. He gives one defining capacity, imagination joined to cooperation, and later the capacity to believe, held by all humans and by no other animal, and from that single property he draws tools, language, art, religion, law, and science. The Creative Spark and Why We Believe run on it. That is an essence by its shape. The plural noun is the tell. Fuentes wants the reach of a species essence while denying he posits one. “The biocultural” does the same labor, a master-substance standing in for the nature he sent away, doing the explaining a nature used to do.
Fuentes dissolves the kinds under dispute, race and sex, and keeps the kinds his synthesis runs on, the human and the biocultural. His nominalism is real and selective at the same time, and the selection tracks which kinds he needs.
A limit. Essentialism as a lens cannot tell you that Fuentes is wrong. A man can dissolve a bogus kind, keep a sound one, and come out right twice. Whether gamete sex cuts nature at a joint, and whether a single imaginative capacity defines the human, are first-order questions in biology and paleoanthropology that the frame brackets and does not pretend to settle. What the frame prices is consistency. The anti-essentialist holds his nominalism where a kind is fought over and drops it where a kind carries his account of what we are. Name that, and you have said something true about the work without ruling on the science under it.
Notes
Stephen Turner’s standing as a philosopher of social science is summarized here.
https://en.wikipedia.org/wiki/Stephen_Park_Turner
The frame I used is his nominalism and his refusal to reify collective abstractions, the strand that runs through his methodological work on Durkheim and Weber and through The Social Theory of Practices (1994), where he treats shared “practices” and “the social” as names rather than things with causal essences.
Turner has no single book devoted specifically to essentialism. His anti-essentialism is the nominalist spine running through his larger body of work. If you cite him by name to skeptical readers, anchor him to nominalism and the anti-reification of “the social,” not to a nonexistent “Turner on essentialism” text. I deliberately stayed away from his anti-normativism, the is/ought or “naturalistic moment” argument, because that is a separate Turner lever.
The distinction between essentialism and nominalism, together with the natural-kinds vocabulary I relied on, including defining properties versus correlated trait clusters, “cutting nature at its joints,” and the realism versus nominalism distinction, is presented in the Stanford Encyclopedia of Philosophy entry on natural kinds.
https://plato.stanford.edu/entries/natural-kinds/
That is a useful source if you want a citable account of the gamete-as-kind argument that does not depend on contemporary culture-war debates.
On the Fuentes claims that support the essay. “Typical clusters of variation” is Fuentes’ own wording from the Academics Write podcast of June 19, 2025, quoted in both Tomas Bogardus’s review and Jerry Coyne’s review.
https://www.realityslaststand.com/p/augustin-fuentes-book-sex-is-a-spectrum
https://whyevolutionistrue.com/2025/09/11/short-review-sex-is-a-spectrum/
The gamete-binary critique from Coyne and Bogardus appears in those same reviews.
Fuentes’ position on race, that biological race is not a natural kind but remains socially real, comes from Race, Monogamy, and Other Lies They Told You, summarized here.
https://www.amazon.com/Agustin-Fuentes/e/B001IO9PXA
The account of human beings centered on imagination, cooperation, and later belief is the central thesis of The Creative Spark and Why We Believe, as reflected in the same bibliography.
Fuentes’ use of the phrase “human nature(s)” appears on his Princeton faculty page and in the Gifford Lectures archive.
https://giffordarchives.org/lecturers/agust%C3%ADn-fuentes
Several points are my own extrapolations and do not require citation. The claim that a cluster is “typical of” a kind, and therefore presupposes the kind it is typical of, is a logical observation about Fuentes’ own wording rather than a sourced claim. The statement that his teachers had already dissolved biological race decades earlier follows naturally from the Sherwood Washburn lineage discussed in the biography. The description of “the biocultural” as a kind of master substance is my characterization of how the concept functions in his argument, not language Fuentes uses about himself.
The concluding pattern, that Fuentes dissolves the disputed kinds while retaining the load-bearing ones, sits only one step away from the coalition and anti-normativist readings I have planned for later essays. I framed it strictly as a question of the scope of nominalism, namely which kinds he treats as real, to keep the essay within the essentialism framework and out of Turner’s anti-normativism.
Fuentes and the Naturalistic Moment
Near the end of Sex Is a Spectrum Fuentes stops describing and gives an order. We need to move past the binary, he writes, and we should do everything we can to make that happen. The sentence reads like the conclusion of the science that came before it. It is not. It is a different kind of claim wearing the same coat, and telling the two apart is the whole of what Stephen Turner’s work on normativity asks of a reader.
Normativism is the family of views that hold there is a special order of facts in the world, the order of oughts and validity and bindingness, that no account of mere causes can reach. The norm binds, and the binding is real, and it floats above the plain facts about who does what and who punishes whom for it. Turner spent a book, Explaining the Normative, taking that order apart. His method is simple and hard to slip. Watch the place where the norm touches the world. He calls it the naturalistic moment. A norm that explains anything has to land on real behavior, and the instant it lands it makes a factual claim about real processes, about training and habit and expectation and sanction. At that instant the plain causal account explains the behavior, and the extra normative substance, the bindingness laid over and above the facts, does no work the causal account did not already do. Pull it out and nothing in the explanation goes missing.
Hold that up to Fuentes and the pattern shows at once. He runs descriptive science and moral command together, and he treats the second as though it fell out of the first.
Take the Darwin essay. In Science in 2021 Fuentes wrote that students should meet Darwin as a man with “injurious and unfounded prejudices” that warped his reading of the evidence. The empirical part is plain and old. Darwin held Victorian views on race and sex, and they show in the text. The word that does the other work is injurious. Injurious is not a finding about Darwin’s data. It is a present-day moral verdict, and it arrives strapped to a teaching instruction, the should, about how the young ought to be raised to read him. Fuentes sets the verdict and the instruction inside a scientific journal as the lesson the anniversary teaches. His critics, Charlesworth and Wright and Coyne among them, kept circling the same spot without naming it. They said he was judging a Victorian by present morals. Turner names it. The moral judgment is a second act laid over the historical one, and calling Darwin’s views injurious tells a reader nothing about the biology that the plain historical description had not already told him. The verdict adds heat, not light.
The sex book runs the same way. Fuentes catalogs variation in bodies, then declares the binary harmful. A reviewer for the Gay and Lesbian Review caught the shape of it without flinching. Fuentes treats binary thinking as harmful to the accumulation of scientific knowledge and to human relations both. Read that twice. The harm is offered as two things at once, an epistemic cost and a moral cost, welded so the reader cannot pry them apart. The naturalistic moment is the word harmful. Harmful makes a factual claim. The binary causes harm, to inquiry and to people. You could study that claim. You could ask whether teaching the binary lowers the quality of research, whether it raises the rate of anything measurable in people’s lives. Fuentes does not run it as a claim to be tested. He states it as a moral fact the science has delivered, and a catalogue of bodily variation delivers no such thing, because no amount of description carries a man across to harm. The harm is asserted. The biology is described. The bridge between them is the part he leaves unbuilt.
Notice what the fusion buys him. Once harm and falsity ride together, a man who doubts the science looks like a man careless of harm, and a man who doubts the politics looks like a man who cannot read biology. The normative residue is not idle here. It works, but the work is protective, not explanatory. It sets the value claim where evidence cannot reach it, behind the science, so that to argue with the ought you have to look as though you are arguing with the is. Turner’s point is that this runs backward. The ought and the is are two claims. The empirical one stands or falls on its own, untouched by how much moral weight a man hangs on it.
Fuentes argues at times as though getting the biology right commits you to his politics, as though to understand sex or race well you must end where he ends. This is the normativist’s old transcendental step, the claim that to do X you have to accept Y. Turner has a blunt answer he calls the mosquito test. If the must were real, no one could hold the one and refuse the other. People do. Coyne grants the biology Fuentes describes and throws out every political conclusion drawn from it. That a man can stand there, the biology in one hand and Fuentes’s politics nowhere, shows the must was never a must. It was a wish dressed as a necessity.
What does the frame leave standing? It says he runs two claims as one and lets the strength of the empirical claim vouch for the moral claim that the empirical claim cannot vouch for. And it does not, on its own, tell you the morals are wrong. The binary may do harm. Moving past it may be right. Compassion may be owed. The frame holds all of that at arm’s length. It insists only that these are claims to be argued on their own ground, with their own evidence, and that smuggling them in under the science shortchanges both. The science earns its standing as science. The morals earn theirs as morals. Fuentes, like most public scientists who want their findings to do moral work, keeps welding the two, and the weld is the thing to watch.
Notes
Turner’s anti-normativism is developed in Explaining the Normative (2010) and in his chapter, “The Naturalistic Moment in Normativism,” which introduces the “naturalistic moment” and the “mosquito test” that I use here.
https://digitalcommons.usf.edu/phi_facpub/180/
The excerpt available there states the central claim, that the normativist must posit a “super-added normative element” that no naturalistic account can capture, and that transcendental arguments claiming “you must have” certain contents ultimately fail. I built the naturalistic-moment reading and the protective-function interpretation directly from that argument. The “mosquito test” is Turner’s own term.
I kept this essay separate from Turner’s nominalism and his critique of essentialism.
On the Fuentes material. The statement that Darwin “should be taught as a man with injurious and unfounded prejudices” comes from Fuentes’ Science editorial of May 21, 2021, as quoted in the critics’ open letter.
Fuentes’ own characterization of Darwin as “a text to learn from, not to venerate” appears on his website.
https://afuentes.com/2021/06/the-descent-of-man-150-years-on/
The argument that binary thinking is harmful both to scientific knowledge and to human relationships comes from the review in The Gay & Lesbian Review.
https://glreview.org/article/where-the-binary-ends/
That review is the strongest source for the is/ought fusion because the reviewer endorses the argument rather than criticizing it. The book’s concluding appeal to “move past the binary” and to “do everything we can to make that happen” is reported from page 150 here.
https://www.realityslaststand.com/p/augustin-fuentes-book-sex-is-a-spectrum
Jerry Coyne’s acceptance of the biological claims while rejecting the political conclusions, which I use as an illustration of the failed “must,” runs through several of his posts, including this one.
https://whyevolutionistrue.com/2025/09/11/short-review-sex-is-a-spectrum/
Several points are my own analysis rather than sourced claims. The observation that “injurious” is a moral judgment rather than a finding about empirical evidence is an analysis of the word. The claim that the alleged harms could be studied empirically is simply the frame’s own naturalistic move. The suggestion that Fuentes “may feel the ought and the is as one thing” is charitable speculation about his intellectual stance. I flag it explicitly as speculation so that it reads as an effort to avoid imputing bad faith rather than as a claim about his state of mind.
The Coyne example touches the sex binary, which belongs in the essentialism essay. Here I use it only to illustrate the failure of the transcendental “must,” not to argue whether sex is a natural kind. I removed every discussion of gametes and natural kinds so that the two essays remain distinct. If you place them side by side, the test is whether a reader could distinguish the normativity essay from the essentialism essay with the names removed. I think the answer is yes. This essay never asks what is real. It asks only what is being asserted as binding.
If John J. Mearsheimer is right in his anthropology, the work of biological anthropologist Agustín Fuentes faces a fundamental challenge. Fuentes has spent his career arguing for “the extended evolutionary synthesis,” emphasizing human plasticity, niche construction, and our capacity for cooperation. He posits that humans are not hardwired for war or defined strictly by tribal competition, but are instead “creative, social, and cooperative” beings who constantly reshape their environments and themselves.
In a liberal framework, Fuentes offers a scientific rebuttal to Mearsheimer’s brand of realism. Where Mearsheimer sees a hard, immutable tribal structure, Fuentes sees biological and social flexibility. He argues that we are not “innate” killers or tribalists, but that our biology allows for a wide array of social arrangements. This view is essential to the liberal project, as it suggests that human nature is sufficiently malleable to move past conflict-prone tribal structures into more cooperative, cosmopolitan forms of existence.
Mearsheimer’s logic suggests that Fuentes’s emphasis on plasticity is a misreading of the core human engine. Mearsheimer acknowledges that humans are social and cooperative, but he argues this cooperation is always oriented inward toward the tribe, not outward toward a universal brotherhood.
If Mearsheimer is right, the plasticity Fuentes documents is not a path to human liberation from tribalism; it is the very mechanism that makes tribalism inescapable. Our biological capacity for cooperation is precisely what allows us to form the tightly knit, defensive, and competing groups that Mearsheimer describes. A human’s ability to “construct a niche” is used to build walls—both physical and psychological—around his primary social group. The more cooperative a group is internally, the more effective it is at competing externally.
Furthermore, Mearsheimer’s point about the “long childhood” and “intense value infusion” provides a structural reality that Fuentes’s evolutionary view often glides over. Fuentes might argue that humans can adapt to new, globalized social realities through education and changing cultural norms. Mearsheimer’s anthropology insists that by the time an individual reaches the point where he can use his critical faculties to contemplate Fuentes’s theories, his tribe has already imprinted a foundational value system that his reason cannot easily displace.
If Mearsheimer is right, Fuentes’s research into human potential provides the how—the biological and social mechanics—of tribal existence, but it fails to address the why. The biological capacity for empathy and cooperation does not manifest as a universal, world-spanning peace; it manifests as a deep, primal loyalty to the specific micro-society that protects the individual. Fuentes describes how we are built to be social, but Mearsheimer describes the inevitable gravity of the groups we build. In Mearsheimer’s world, our cooperative biology is the very tool we use to ensure our tribe survives at the expense of others.
The debate between Fuentes and Mearsheimer captures a foundational divide in intellectual history. It sets an evolutionary model of open-ended cooperation against a structural model of defensive tribalism. Both thinkers agree that humans are profoundly social and cooperative. They diverge entirely on the boundaries of that cooperation and its ultimate purpose.
Fuentes argues for a concept called niche construction. Humans do not merely adapt to their environments; they actively reshape them through creativity, shared belief, and cross-group connection. In his view, human evolution is defined by a capacity to expand the circle of empathy and collaboration. Cooperation is an open system. It can scale from the family to the tribe, and ultimately to global networks.
Mearsheimer views cooperation as a closed system. He argues that human nature is tribal at its core. The primary reason for our social nature is basic survival. Individuals must embed themselves within a specific society to protect themselves from external threats. Cooperation is always inward-facing, designed to strengthen the internal cohesion of the group. This internal unity exists precisely to compete more effectively against rival groups. For Mearsheimer, scaling cooperation to a universal level is a structural impossibility.
The two models rely on completely different views of how human preferences and moral codes are formed.
Fuentes focuses on human flexibility. Our biology does not dictate fixed political or social outcomes. Because human culture and behavior are highly malleable, societies can use critical reason and education to dismantle hostile tribal divisions and engineer more inclusive, cosmopolitan systems.
Mearsheimer argues that reason is the least important way humans determine their preferences. The long human childhood ensures that an individual faces intense socialization before his critical faculties form. By the time he can think for himself, his primary group has already imposed an indelible worldview. Human beings are constrained by this early conditioning, making true cosmopolitan detachment an illusion.
For Fuentes, mass violence and war are not inherent to human biology. They are historical and cultural inventions, emerging alongside sedentary agriculture, property accumulation, and specific social structures. Since warfare is a learned cultural device, it can be unlearned through alternative social setups.
Mearsheimer argues that conflict is the inevitable result of a world composed of distinct social groups. Because there is no higher authority to protect a group if a rival decides to attack, tribes must always prioritize their own security and survival. Conflict does not stem from a cultural mistake or a lack of imagination. It is the logical operation of separate, self-interested social entities seeking to survive in an anarchic world.
If Fuentes is right, human history is an ongoing, creative experiment with the potential to transcend tribal boundaries. If Mearsheimer is right, that experiment is permanently bounded by our social architecture. Our capacity for cooperation is simply the tool we use to ensure our specific tribe survives at the expense of others.
If David Pinsof is right, the anthropological work of Agustin Fuentes represents another attempt by the academic class to frame human history as a series of errors that intellectuals must correct. Fuentes spends his career arguing against what he calls myths of human nature. In books like Race, Monogamy, and Other Lies They Told You, he claims that humans are not naturally violent or divided into biological races. He argues instead that cooperation and shared imagination drive our evolution.
A Pinsofian analysis strips away this optimistic narrative. Human conflict, racial divisions, and tribal warfare do not happen because prehistoric humans or modern citizens suffer from a misunderstanding. Factions use ingroup solidarity and outgroup hostility to protect their resources, secure territory, and compete for status. The behaviors Fuentes labels as myths are actually functional, self-serving strategies that helped groups survive in a zero-sum world.
By defining these deep evolutionary adaptations as lies or misconceptions, Fuentes creates a high-status mission statement. This position makes the biological anthropologist the necessary authority to repair a broken society. His theories of cooperation offer elite readers a way to signal their own moral superiority over the supposedly ignorant and aggressive masses.
His book Why We Believe outlines how human imagination shapes religion, economies, and love. From Pinsof’s view, these belief systems are not innocent patterns of shared meaning. They are coalitional tools used to build alliances and dominate rivals. Fuentes presents a story where human behavior can be improved through education and better social design. If Pinsof speaks the truth, human beings already understand their incentives perfectly. The call to bust myths is simply an effective lever to gain prestige and authority within the university hierarchy.
Bio Notes
The opening Bali scene. The “we both wait together” line from the bus driver, and the second guide’s remark that both man and monkey go to work when the tourists arrive, come from Fuentes’ 2010 paper, “Naturalcultural Encounters in Bali,” as quoted here and in the original article. Padangtegal Monkey Forest in Ubud is his documented field site.
https://www.multispecies-salon.org/we-both-wait-together/
https://anthrosource.onlinelibrary.wiley.com/doi/full/10.1111/j.1548-1360.2010.01071.x
The shade, the heat, the notebook, the tour buses, and the cameras are self-evident texture for that place and that kind of fieldwork. Fuentes’ comments about catching himself, the field “humbling” him, and the behavior turning out “so primate” come from the Sinai and Synapses interview.
https://sinaiandsynapses.org/content/humans-and-our-relatives-a-conversation-with-agustin-fuentes/
Origins and training. Fuentes was born on July 30, 1966, in Santa Barbara. His father, Víctor Fuentes, was a Madrid-born Hispanist who left Spain after the Civil War.
https://en.wikipedia.org/wiki/Agust%C3%ADn_Fuentes
The description of a household speaking “two languages, science and humanities” is a reasonable extrapolation from having a literary-scholar father and from Fuentes’ own movement between the sciences and humanities. I could not find a source describing the home directly, so treat that sentence as interpretive. Degree dates, B.A. (1989), M.A. (1992), and Ph.D. (1994), come from his Princeton faculty page.
https://anthropology.princeton.edu/people/faculty/agustin-fuentes
The Phyllis Dolhinow (1933-2019) and Sherwood Washburn (1911-2000) lineage, together with the characterization of Washburn’s “new physical anthropology,” comes from your uploaded document. The adviser relationship is supported by Dolhinow and Fuentes’ co-edited volumes listed on the Princeton page.
Fieldwork and ethnoprimatology. The Mentawai langur work in the late 1990s, followed by studies of macaques in Bali, Gibraltar, and Singapore, pathogen transmission, and the development of ethnoprimatology alongside Leslie Sponsel come from Wikipedia, the Princeton publications list, and Grokipedia.
https://grokipedia.com/page/Agust%C3%ADn_Fuentes
Grokipedia is the weakest source here, so verify the 1995-1998 Mentawai dates independently. The descriptions of himself as “an anthropologist who happens to carry biological training” and “maybe the first biological anthropologist to publish in Cultural Anthropology” paraphrase his responses in the American Anthropological Association president’s interview. The description of macaques as “the most successful primates after humans” reflects his own framing there.
https://virginiarosadominguez.wordpress.com/presidents-studio/agustin-fuentes/
Imagination and cooperation. The Creative Spark (2017), the finger-painting-and-hand-axe argument, and the claim that cooperation preceded warfare come from his published bibliography.
https://www.amazon.com/Agustin-Fuentes/e/B001IO9PXA
The 2018 Gifford Lectures at Aberdeen, which became Why We Believe (2019), are documented here.
https://giffordarchives.org/lecturers/agust%C3%ADn-fuentes
Race, Monogamy, and Other Lies They Told You (2012). The three central myths, biological race, innate aggression, and men and women as natural opposites, are summarized in the publisher’s description.
https://www.amazon.com/Agustin-Fuentes/e/B001IO9PXA
The Darwin controversy. Fuentes’ Science editorial appeared on May 21, 2021.
https://www.science.org/doi/10.1126/science.abj4606
His own follow-up appears here.
https://afuentes.com/2021/06/the-descent-of-man-150-years-on/
Brian Charlesworth’s response appears here.
Jerry Coyne’s criticism appears here.
Robert J. Richards’ response appears here.
https://whyevolutionistrue.com/2021/07/08/bob-richards-answers-agustin-fuentes/
The Robert Wright and Fuentes exchange, with Wright asking for quotations, Fuentes directing him to chapter 7, and Wright concluding that Darwin described displacement without endorsing it, is summarized here.
I reconstructed that exchange from Coyne’s account rather than from the original social media posts. If you want verbatim quotations, you would need to consult Wright’s original thread.
Sex Is a Spectrum (2025). Princeton University Press published the book on May 6, 2025. It runs to roughly 150 pages. The bluehead wrasse opening is summarized in Edward Hagen’s review, which also presents his “variation without explanation” critique.
https://blog.edhagen.net/posts/2025-08-07-review-sex-is-a-spectrum/
A favorable review by Lixing Sun appears in Psychology Today.
https://www.psychologytoday.com/us/blog/lies-and-deception/202505/the-case-for-a-fluid-view-of-sex
Another favorable review appears in The Gay & Lesbian Review.
https://glreview.org/article/where-the-binary-ends/
Critical reviews include Tomas Bogardus at Reality’s Last Stand.
https://www.realityslaststand.com/p/augustin-fuentes-book-sex-is-a-spectrum
Jerry Coyne also reviewed the book here.
https://whyevolutionistrue.com/2025/09/11/short-review-sex-is-a-spectrum/
Fuentes’ phrase “typical clusters of variation” comes from the Academics Write podcast on June 19, 2025, and is quoted in both Bogardus and Coyne.
Present position. Fuentes has been at Princeton since the fall of 2020. He was elected to the American Academy of Arts and Sciences in 2020, received the inaugural American Association of Biological Anthropologists Communication and Outreach Award, and serves as a National Geographic Explorer.
https://anthropology.princeton.edu/people/faculty/agustin-fuentes
https://explorer-directory.nationalgeographic.org/agustin-fuentes
His participation in the Rising Star and Homo naledi projects with Lee Berger, John Hawks, and Keneiloe Molopyane is listed on the Princeton page. The statement that Homo naledi “may have handled its dead” reflects the contested burial hypothesis, which I intentionally kept qualified.
Two things I left out. There was a side episode in which an Edinburgh anti-racist group reportedly attempted to suppress a paper connected to this controversy, but the reporting blurred whose paper was involved and on what grounds, so I omitted it rather than risk misattribution. I also left out the older Mishawaka and Los Angeles residence note because it belongs to the Notre Dame years and now reads as outdated.
