Introduction

The ancient Greek historian Thucydides said that “human nature is the one constant through human history – it is always there.” From a literal interpretation, this is tautologically correct; the existence of human history implies the existence of some behaviors that accompany it, which can be characterized as ‘human nature’. In fact, the more provocative word in this quote is that of ‘constant’ – is it that the existence of some ‘human nature’ is constant, or is it that there is some descriptive essence of human nature that is complete and unchangeable? However, from an evolutionary biology perspective, change is perhaps the only constant – and human nature is no exception. One of the most dynamic debates in evolutionary biology is about this: what are the mechanisms through which human nature changes? Is there anything that doesn’t change, and can these features be characterized?

Philosophers throughout history have studied human nature through various perspectives, from Aristotle and his “theory of four causes” and the “theory of innate goodness” from the Confucian school of thought, to the various theological perspectives offered by religious scholars and texts, to the ideas proliferated by thinkers like Descartes, Hobbes, and Rousseau during the Enlightenment period of European history. In more recent history, colonialist ‘science’ offered explanations of human nature to justify colonialism and white supremacy, such as the pseudoscientific phrenology proliferated by Franz Joseph Gall in the eighteenth century which related skull measurements to race and human nature. Then, the introduction of Charles Darwin’s theory of evolution and natural selection in the mid-nineteenth century completely transformed the way in which things like human nature were discussed in the scientific community. Evolutionary biologists have since contested the extent of the role that natural selection has in influencing phenomena like human nature. The relationship between the study of Darwinian evolution and the course of global history since this period has resulted in a complex and dynamic development of the scientific examination of human nature that continues to be relevant to this day.

In this paper, I explore the historical and scientific exploration of human nature from an evolutionary biology perspective. In particular, I discuss adaptationism versus structural approaches to understanding human nature and human society, focusing on expositions from the 1970s and the debates surrounding them. In particular I describe the arguments against adaptationism made in the paper The Spandrels of San Marco and the Panglossian Paradigm by Richard Lewontin and Stephen Gould, as well as some of the contrary arguments in favor of adaptationism such as E. O. Wilson’s application of the theory of sociobiology onto human nature. As part of this discussion, I examine the relationship between political ideology and the scientific study of biology. I also consider the contemporary relevance of this analysis of human nature and the consequences this conversation has for the future.

The Spandrel

The 1970s were a tumultuous time in human history, particularly notable for being a period of fierce political movements and protests across the world – but this decade was also a period of serious debate in evolutionary biology regarding the relationship between natural selection and human nature. The phenomena of natural selection describes the changes in inheritable traits based on relative advantages in reproduction and survival, which is a major factor influencing evolution in populations. To apply natural selection to explain human nature means to identify changes in human nature as driven by the relative success for the reproduction and survival of human beings among certain humans. This was discussed for many years, especially with the works of A. R. Wallace who emphasized adaptationism, that the traits in different species are the result of adaptations shaped by natural selection.

However, the debate exploded in the 1970s with E. O. Wilson’s book Sociobiology: The New Synthesis. Wilson sought to describe the relationship between evolutionary biology and social behavior through his theory of sociobiology; the real controversy started in the final chapter of his book where he applied his theory to human behavior. This theory was critiqued heavily by many other biologists, most notable being Stephen Gould and Richard Lewontin who argued that this theory essentialized human nature to the genetics of individual humans, a form of biological determinism that neglected the social construction of human nature and the deep structural relationships between how human nature takes shape and the formation of human society. Wilson later elaborated on the subject of human sociobiology in his work On Human Nature in 1975 – as he poses in it – “Human sociobiology asks: What might the human instincts be? How do they fit together to compose human nature?” Wilson’s theory argued that natural selection selected for advantageous traits in human behavior and morphology, and consequently that evolution of human nature was guided by the selection of these advantages. Wilson also made efforts to list certain inherent qualities of human nature, such as arguing that humans were inherently aggressive. These works and ideas received heated criticism from many including Gould and Lewontin.

This decade of discussion culminated in the widely famous paper called The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme, published by Stephen Gould and Richard Lewontin in 1979. The title of the paper is inspired by the decorated spandrels featured in a lot of Renaissance architecture, describing the somewhat triangular region between arches and a dome. These regions of the architecture are often very beautiful and considered by some as an origin of the artistic work, but they actually emerge as a consequence of the relationship between the different parts of the full architectural dome, with the mosaic design featured on them being largely a consequence of this geometry. This example seeks to demonstrate that the seemingly evident explanation for a feature is not actually the root origin of why the feature is present – an architecture analogy for a subsequent critique of adaptationism in evolutionary biology. While the paper critiques the adaptationist methodology in general, its relevance is particularly significant in critiquing the application of adaptationism to human nature.

In a more recent 2015 interview, Lewontin described one motivation for the paper being Wilson’s work on sociobiology, writing that this theory was “contextually relevant”. However, later in the same interview, Lewontin maintained that they would have “written exactly the same paper if sociobiology had never come into existence”, and that the main reason for the paper was to criticize the “tendency to try to find, in every instance, some selective advantage for things”, and to instead demonstrate “that there are a whole variety of forces that give rise to observed traits and they are not all directly selected for”.

This appropriately characterizes the core essence of the paper – a critique of adaptationism, or the belief that natural selection is a complete or near-complete descriptor of human nature, and the traits we observe are evolved adaptations. The paper begins with a description of adaptationism and how those who study it employ the framework. As they describe it, adaptationism “regards natural selection as so powerful and the constraints upon it so few that direct production of adaptation through its operation becomes the primary cause of nearly all organic form, function, and behavior” (Gould & Lewontin, 4). Scientific studies using adaptationism rely on separating an organism into individual traits, which are each optimized by natural selection; if a given trait does not seem to be optimized, it is explained as a ‘trade-off’ for another related trait that is being optimized. Altogether, the whole organism is evolutionarily optimized through this adaptationist approach of natural selection. Lewontin and Gould describe this approach to understanding biological systems and behaviors as limiting – in particular, they claim that while many adaptationists do acknowledge that natural selection does not completely describe evolutionary biology, they do not seriously consider alternative explanations for phenomena: “the admission of alternatives in principle does not imply their serious consideration in daily practice” (Gould & Lewontin, 5). Instead of looking for alternate frameworks, those supporting adaptationism usually treat the failure of one application of adaptationism by looking for another adaptive argument, argue for a weaker version of the first one, or justify the failure by suggesting incomplete context of the organism’s behavior. In addition, utility is emphasized when thinking about the presence of traits, rather than other reasons for traits being present, which once again reinforces the adaptive paradigm of advantageous traits from an evolutionary perspective. By following this ‘programme’, many scientists reach conclusions that completely misinterpret the actual phenomena or only partially explain it.

Gould and Lewontin sought to contextualize Darwinist natural selection appropriately and showcase how many interpretations are problematic. In fact, Lewontin in his critiques of adaptationism and biological determinism did not disavow Darwin’s theory itself – rather he referred to the works of scientists like Wilson as “vulgarizations of Darwinism” which posited the science of natural selection as an “optimizing agent” (Gould & Lewontin, 1). They write, “Although Darwin regarded selection as the most important of evolutionary mechanisms (as do we), no argument from opponents angered him more than the common attempt to caricature and trivialize his theory by stating that it relied exclusively upon natural selection” (Gould & Lewontin, 9). Lewontin and Gould emphasize the pluralism required when considering the factors shaping evolution. On the contrary, they specifically critiqued the work of A. R. Wallace, considered a cofounder of the theory of natural selection, and explained how Darwin’s explanations differed from Wallace’s argumentation in key different places, leading to the proliferation of adaptationist logics.

Lewontin and Gould continue to describe alternative or complementary approaches to the adaptive paradigm. Firstly, it is possible that neither selection nor adaptation occur in any significant way – in particular genetic drift can explain changes in allele frequency, or allele frequency can actually remain the same even with natural selection. In addition, selection or adaptation could not be relevant for the part being studied, but actually the changes could just be related to selection in a different part of the organism. They also describe that selection can happen without adaptation, or adaptation can happen without selection, so these are not actually unified processes. There can also be multiple adaptations that a species can take to solve some problem related to survival, and to create a hierarchy of these adaptations to measure utility can be misleading. Finally, there may be both adaptation and selection, but the observed adaptation may not be a direct consequence of the reason it was developed – the example given by the authors is that blushing during sexual attraction does not serve to explain why blood is red, so those two features cannot necessarily be related in any explanatory capacity.

The last section of the paper considers another way to view evolution based on the Bauplan, which refers to the blueprint or the group of features common to a given phylum of organisms, such as bone structure or wings. While natural selection does influence evolution, the interconnected nature of many of the features of many organisms end up leading to many constraints which limit adaptation. Consequently, it becomes perhaps more interesting to study the relationship between these constraints themselves. This angle of viewing evolution reveals that while natural selection still remains relevant, centering it as the fundamental force of change in all cases is a deeply limiting and inappropriate methodology. Lewontin and Gould end the paper by writing:

“Too often, the adaptationist programme gave us an evolutionary biology of parts and genes, but not of organisms … A pluralistic view could put organisms, with all their recalcitrant yet intelligible complexity, back into evolutionary theory” (Gould & Lewontin, 19).

Regardless of the details of what forces shape a specific case of evolution, the point remains that natural selection does not completely describe the evolution of traits, and particularly does not describe characteristics nor the changing of human nature.

On Ideology and Contemporary Relevance

The quest to understand human nature is hallmarked (and tainted) by various epochs and scientists – from the orientalist and racist descriptions of human races during the onset of colonization, to the debates after Darwin regarding the veracity and completeness of the theory of natural selection. Yet one period that often remains overlooked are the fierce discussions about the relationship between human nature and natural selection in the late 20th century, featuring many prominent evolutionary biologists and ecologists including E. O. Wilson, Stephen Gould, and Richard Lewontin. These debates will invariably continue into the future – the contradictions among human society mean that the contradictions in how the scientific community understands human society will persist.

With the 1970s being a politically contentious period, the relationship between politics and science was heavily discussed by the relevant scientists. One of Wilson’s primary critiques of Lewontin and other ‘radical’ scientists was their incorporation of politics openly in their scientific endeavors. Wilson, on the contrary, claimed to approach the field from a more apolitical ‘scientific materialist’ perspective. Wilson specifically criticizes Lewontin at lengths and writes in “Science and Ideology” that:

“By adopting a narrow criterion of acceptable research deserving the title of science, Lewontin freed himself to pursue a political agenda unencumbered by science.”

Wilson believed that scientists like Lewontin adapted the sociological frameworks of Marxism and dialectical materialism in a dogmatic way which prevented them from engaging in science honestly, writing that “political ideology can corrupt the mind, and science.”

Lewontin also spoke extensively about the relationship between politics and science – except for Lewontin, these were not two subjects to separate, but rather to see how they reflect one another was essential to understanding both more completely. In this light, Lewontin argued that Wilson’s anti-leftist stances and determinist approach to human nature through sociobiology were also ‘political’. In his fervent support of the adaptationist paradigm and in particular the application of sociobiology to human beings, Wilson inherently involved ideology in his science as well. Wilson’s works made explicit claims about human nature – writing in Sociobiology: The New Synthesis that:

“Human beings are absurdly easy to indoctrinate it. They seek it.”

While some statements made by Wilson may be potentially poignant observations from a literary or poetic perspective, from a scientific perspective they hold notorious conclusions which often lead to potentially racist ideas. Consequently, the goal as Lewontin explained was not to remove politics from science, but to further examine the role it plays in influencing and shaping the development of scientific knowledge.

Lewontin wrote more about the relationship between ideology and science in his 1991 book Biology as Ideology. When describing the relationship between Wilson’s sociobiology and the capitalist worldview it reflects, Lewontin writes:

“Despite the name sociobiology, we are dealing with a theory not of social causation but of individual causation. The characteristics of society are seen as caused by the individual properties that its members have, and those properties, as we shall see, are said to derive from the members’ genes.” (Lewontin, 57)

This emphasis of the individual over the collective is a very capitalist mentality, which not only reflects the capitalist environment in which the scientific discovery emerged, but also demonstrates how the proliferation of this theory can reify capitalism itself. Just like human nature is dependent on so many social factors and can change over time and space, so too can ideology – in some ways they are inextricably linked. Lewontin writes about this universality of change:

“There is nothing in our knowledge of the world to suggest there is any particular balance or harmony. The physical and biological worlds since the beginning of the earth have been in a constant state of flux and change, much of which has been far more drastic than anyone can now conceive.” (Lewontin, 78)

Viewing human nature as dynamic and in constant flux makes us realize that change really is possible – this is a scientific truth and a powerful aspiration which can give us courage to dare to dream of better worlds and struggle towards them.

Most people in this world are not aware of the scientific literature surrounding human nature and human society – does this make studying it irrelevant? I think it remains so important because while the study of science may seem exclusive and contained within certain environments, the implications of scientific knowledge touch all of society, even those who are scientifically illiterate. Especially with the legitimacy that scientific study receives, to firmly and resolutely explain that adaptationism and natural selection are insufficient in explaining human nature helps to demonstrate to society that things like financial success aren’t correlated with advantageous ‘human nature’. This is an important task that remains incomplete – we live in a deeply unequal society that has ‘inherited’ many of the problematic mindsets and faux-scientific understandings of human nature and race that need to be challenged. Just as scientific ‘theories’ with racist implications are used to justify racist societies, expanding on scientific theories with antiracist conclusions can help to create the antiracist societies that we desire. Until those antiracist societies are created, struggling against the unjust societies and the problematic scientific theories that uphold them remains a quintessential task – for scientists, historians, and all people alike.

References

• Darwin, Charles (1872). The Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (6th ed.).
• Finger, S. (2019, July 26). Franz Joseph Gall and the origins of Phrenology. Becker Medical Library.
• Gould, S. J., & Lewontin, R. C. (1979). The Spandrels of San Marco and the Panglossian Paradigm: A critique of the adaptationist programme. Proceedings of the Royal Society of London. Series B. Biological Sciences, 205(1161), 581–598.
• Lewontin, R. C. (1991). Biology as Ideology. House of Anansi.
• Lewontin, R. C. (2022, January 11). Billions and billions of demons. The New York Review of Books.
• Lewontin, R., & Wilson, D. (2018, February 27). The spandrels of San Marco revisited: An interview with Richard C. Lewontin. This View Of Life.
• Wallace, A. R. (1889). Darwinism: An exposition of the theory of natural selection, with some of its applications. Macmillan.
• Wilson, E. O. (1975). Sociobiology: The New Synthesis.
• Wilson, E. O. (1979). On Human Nature.
• Wilson, E. O. (1995). Science and ideology. Academic Questions, 8(3), 73–81.
• Wilson, E. O. (2009). A Chat with E. O. Wilson. Research in Review.
• Yen, H.-C. (2015). “Human Nature and Learning in Ancient China.” In Education as Cultivation in Chinese Culture (pp. 19–43). Springer.