Evolution & Natural Selection, Anthropologically!

Update: This page was written in 2011 as an attempt to push anthropology textbooks toward better explanations of evolution and natural selection. I particularly appreciate the textbook Anthropology: What does it mean to be human? on these issues and see the 2021 lecture:

Ideas about evolution and natural selection stem from the previous section on Anthropology and Human Nature. In the nineteenth century, such speculations shifted from the philosophical and religious spheres into the scientific sphere and the development of evolutionary theory.

Evolutionary theory and natural selection are important to anthropology as frameworks for understanding species change and human origins. However, Biological Anthropology emphasizes the complexity of evolutionary processes and how natural selection is much more than “survival of the fittest.” Anthropology stresses the richness and diversity of evolutionary processes, cautioning against the reduction of evolutionary processes to overly simplistic mechanisms:

In The Origin of Species . . . Darwin had virtually nothing to say about human evolution. Indeed, he had nothing really to say about evolution at all, for the word appears only once in the entire book–in the very last sentence! Instead, he spoke of “descent with modification”. Only subsequently, largely as a result of a colossal mistake perpetrated by the philosopher Herbert Spencer and compounded by generations of biologists ever since, was the concept of evolution substituted for that of descent with modification. (Tim Ingold, Against Human Nature 2006:264)

Charles Darwin preferred to characterize his explanation as “descent with modification.” Only later did people insist on using the term evolution. Darwin was originally correct. Using evolution and even natural selection as terms to describe observed natural processes is problematic. We will not retroactively correct this terminology–anthropology will continue to use the terms evolution and natural selection, and anthropology remains at the forefront of understanding and teaching about human evolution research and natural selection. However, we should recognize how much baggage the terms evolution and natural selection have acquired and be on the lookout for common misconceptions.

Evolution is not a progressive march via natural selection

Even as biologists and others are now trying to explain there is nothing inherently progressive about the evolutionary process, that it is fittest within a particular and changing environment, it has become almost impossible to separate the idea of progressive march from the word evolution. Evolution is not a progressive, unilineal track. There is no guidance inherent to the process, no in-built directionality. Organisms can become simpler or can become more complex. Sometimes a simpler organism will be better adapted to a changing environment.

One of the most eloquent arguments against a built-in evolutionary directionality via natural selection is Stephen Jay Gould’s Full House: The Spread of Excellence from Plato to Darwin (1996). Gould’s examples are fascinating: from the assertion we are still in the “age of bacteria” and that bacteria are still the most evolutionarily successful organisms; to a much fuller and more complex picture of the evolution of the horse; to an illustration of the “drunk man’s walk” describing how complexity arises randomly and not inevitably–it’s Gould at his finest.

Nevertheless, Gould’s book is not entirely without problems. The examples may now be seen as dated, and since Gould has been under attack, his ideas might be discounted (see Mismeasuring Gould in “The Mismeasure of Science”). I also found that by stressing so much the randomness and improbability of human emergence, the book paradoxically began to reinforce the counter-argument, perhaps not entirely accomplishing Gould’s purposes. Nevertheless, it is eloquent support for banishing notions of a built-in progressive march to evolution. (I am grateful to Patrick Clarkin for a discussion of Full House, and letting me know about critiques that Gould underplays natural selection.)

Evolution is not just natural selection

Natural selection is of course an important mechanism of evolution. But there are other mechanisms, like sexual selection. As Richard O. Prum notes in The Evolution of Beauty, “evolutionists have tended either to downplay sexual selection or ground it in the logic of adaptation” (quote via the review by Alva Noë “Aesthetic Evolution In The Animal World”)

Then there is the fact that organisms inevitably alter the conditions of the environment, wittingly and unwittingly, which in turn alter the conditions of selection for the next generation. This insight is at the basis of the idea of niche construction which has been an important development in evolutionary theory. However, the term evolution is almost always equated with natural selection. Natural selection, in turn, is always talked about as “survival of the fittest” without adding the point that fitness can only occur within a specific and ever-changing environment.

New York Times columnist David Brooks illustrates this mis-thinking with Nice Guys Finish First (2011). Starting from an impoverished view of evolution and natural selection, Brooks trumpets the importance of revisionist understandings. However, he would not need revisionism if the original richness of “descent with modification” had been developed.

Michael Shermer combines these two issues in A Skeptic’s Take on the Public Misunderstanding of Darwin (2009). Shermer laments “two myths about evolution that persist today: that there is a prescient directionality to evolution and that survival depends entirely on cutthroat competitive fitness.” Instead, Shermer emphasizes selection is a process, not a force. There is no inherent directionality. Fitness can arise from cooperation and aid, not just competition.

There are several resources for thinking anthropologically about evolution. My preferred Introduction to Anthropology textbook, Anthropology: What Does It Mean to be Human? takes a non-directional approach and is one of the few textbooks to discuss and emphasize niche construction. Lavenda and Schultz use niche construction to introduce the idea of agency in evolution, that living creatures play an active role in the evolutionary process. They return to this idea to discuss human evolution and the domestication of plants and animals. Emily Schultz, one of the co-authors, brings a sophisticated perspective on these matters and has written an interesting article Resolving the Anti-Antievolutionism Dilemma: A Brief for Relational Evolutionary Thinking in Anthropology (2009):

What difference would it make if anthropology incorporated relational evolutionary thinking? First, by rejecting the mainstream “neo-Darwinian” position that ontogeny (development) contributes nothing to phylogeny (evolution), it decenters the focus on genes as prime movers, offering clear alternatives to eliminative reductionism. By acknowledging the evolutionary productivity of developmental processes, relational evolutionary perspectives could thereby help shift discussion away from sterile nature–nurture debates. Second, within this enlarged terrain, it will be possible to address matters of anthropological concern that “neo-Darwinian” perspectives either ignore or handle poorly. For example, all the relational approaches discussed here reveal the way structural features of evolutionary processes impinge on each other and how that articulation can give rise to new structures and functions that feed back on themselves, pushing the processes along sometimes surprising paths. Both biological and cultural evolution are reconfigured once the split between inside and outside processes is disallowed: otherwise mysterious events that appear to defy explanation begin to make sense when the underlying processes and infrastructures that scaffold them are acknowledged. (2009:234)

For more on evolution as cooperation, see The Mermaid’s Tale: Four Billion Years of Cooperation in the Making of Living Things by Kenneth Weiss and Anne Buchanan (2009). Based on a continuing investigation of the themes in their book, the authors run an excellent blog on matters related to evolution, also titled The Mermaid’s Tale. See the 2012 post A modest proposal: Please make us teach creationism for related material and that corresponds to some of the suggestions from the Teaching Theories Controversy articles mentioned below, and also see their Things genes can’t do in Aeon Magazine (April 2013).

Human history cannot be explained by evolutionary mechanisms

People talk about the “evolution of markets” or the “evolution of law.” There may be some parallels between processes that occur in the social world and processes of biological evolution, but in general these comparisons lead to many dead-ends and false starts. It is time to put such dubious associations to rest. To explain contemporary institutions, we need a detailed and empirical history, not an explanation through selective mechanisms. As Jonathan Marks puts it in “The biological myth of human evolution”:

While it may be attractively pseudoscientific to imagine human evolution as simply biological history driven by simple biological processes, the most fundamental aspects of human evolution belie that assumption. They are not biological features with biological histories, but biocultural features with biocultural histories. To assert the equivalence of, say, bird plumage and sports cars in attracting mates (Diamond, 1992, p. 175) is to ignore the fact that the sports car is manufactured and sold, and has only been in existence for a few generations. The sports car is not a biological fact, as the bird’s plumage is, but an artefact, with an entirely different ontology. Their equivalence is not a fact of biological evolution, but a metaphor-like equating a tree and an umbrella for both providing shade. To understand any aspect of human evolution as if it were like bird plumage may thus be very misleading. (Marks 2012:148; see also the blog-post Anthropology is Necessary).

Or, as Tim Ingold put it in The trouble with ‘evolutionary biology’:

By all means let us seek a way of embracing human history and culture within a wider concept of evolution: not, however, by reducing history to a reconstructed phylogeny of cultural traits but by releasing the concept of evolution itself from the stranglehold of neo-Darwinian thinking, allowing us to understand the self-organizing and transformational dynamics of fields of relationships among both human and non-human beings. If, as Kuper (1994:1) asserts, ‘we are all Darwinians now’, then, by the same token, we are all Marxians, Weberians, Durkheimians, Boasians, and so on. That is to say, we acknowledge Darwin as one of many thinkers who have fundamentally shaped our modern understanding of life and its conditions, but do not pretend–as do neo-Darwinian proselytes–-to find in his work a holy grail that consigns all else to worthless idolatry. (2007:17)

Evolution and natural selections are processes, not things

The term evolution leads people to assume an outcome, or a noun, or one coherent line of advance via natural selection. Evolution and natural selection are really ongoing processes with lots of little mechanisms and quirks, and a tremendously varied research agenda. Seeing evolution as a thing also makes it easier to dismiss. It is easy to say “I don’t believe in evolution.” But does anyone say “I don’t believe in descent with modification”? A helpful resource for thinking about processes is Evolution in Four Dimensions by Eva Jablonka and Maron J. Lamb (2005).

Agustín Fuentes points a way forward in a 2013 PopAnth article “Behaviour evolves, but evolution is a lot more than ‘survival of the fittest’”:

Evolution of human behaviour is always a synergy of multiple processes, not just the product of selection on genes. Natural selection, the process by which variants have differential representation in subsequent generations, is just one of the many processes in evolution. When we think about human behaviour it is a mistake to think that our biology exists separate from our social and structural ecologies or that our cultural selves are not constantly entangled with our biological landscapes. Thinking about evolutionary processes in a modern context gives us an improved chance at getting better answers to questions about the evolution of human behaviour.

Evolution is not belief

The very idea that evolutionary theory is something people should “believe in” (or not) is rather misplaced. We are talking about evaluating evidence and debates. What is important is not the beliefs, but to understand the processes and mechanisms of evolution, and to become familiar with the picture of human emergence.

As Immanuel Wallerstein writes in The End of the World As We Know It, “we must most of all lower our arrogance decibels” (1999:156). People are not going to be persuaded by arrogant positioning and invocations of intelligence and authority. As Barbara J. King asks, Will Richard Dawkins Drive a Stake Through the Heart of the ‘Reason Rally’? “In the meantime, the rest of us, scientists, science writers, and followers-of-science alike, can opt to rally around a different principle. Whatever our position on the continuum from deep faith to ardent atheism, we can lose the sneers. We can explain and, when necessary, defend science with rigor and passion and genuine civility.”

Accepting evolutionary evidence and understanding human continuity with all of nature does not mean accepting everyone who tries to claim the mantle of evolution. In a provocative history of anthropology and evolutionary thought titled Why were the first anthropologists creationists?, Jonathan Marks offers a compelling distinction and call to scientific responsibility:

The acceptance or rejection of “evolution” may have rather more to do with the particular representation of evolution being offered, its rigor and its implications, than it does with the general intelligence of the target audience. That, in turn, would imply a greater measure of responsibility on the part of the scientific community toward the public, the responsibility to differentiate among the various invocations of Darwinism so that the public knows what it is accepting or rejecting, and that invocations of evolution are not all equally credible. That is to say, it is the responsibility of the scientific community to explain that it is possible to reject the racism of Philippe Rushton or James Watson, the evolutionary psychology of Steven Pinker, or the fanaticism of Richard Dawkins, and yet not be a creationist. (2010:226)

This injunction is also a great way to begin the next section on Biological Anthropology and Racism.

Updates on Evolution & Natural Selection

  • 2018: Agustín Fuentes in Human niche, human behaviour, human nature provides a succinct summary of why we need to understand the Extended Evolutionary Synthesis, and how this relates to questions of human nature discussed in the previous section on Anthropology and Human Nature.
  • 2017: See the Speaking of Science Analysis by Biological Anthropologist Holly Dunsworth in the Washington Post. In “How Donald Trump got human evolution wrong” Dr. Dunsworth makes a strong case for re-considering standard narratives of human evolution and natural selection:

    Evolutionary theory has grown up since its conception. Based on mountains of observations of genes and traits over generations, evolutionary scientists have developed much more skepticism toward explanations that lean too dogmatically on natural or sexual selection. Scientists increasingly resist the temptation to assume that everything evolved “for” a single or specific reason, and that everything must exist because it boosted the survival and reproduction of those who passed it on. We know that perpetual mutation and the chance of passing along (or not passing along) traits occurs within complex cooperative systems with constant biological change.

Next: 1.3 – Biological Anthropology and Racism

Previous: 1.1 – Anthropology and Human Nature

To cite: Antrosio, Jason, 2011. “Evolution and Natural Selection: Anthropologically!” Living Anthropologically website, https://www.livinganthropologically.com/biological-anthropology/evolution-natural-selection/. First posted 16 May 2011. Revised 3 September 2018.