ABSTRACT
Do evolutionary processes, strictly speaking, occur in non-biological contexts, or is ‘evolution’ purely confined to living entities? Can evolutionary processes be distinguished from the contingent details of biology and abstracted into a more generally applicable theory? Are apparent evolutionary patterns in culture truly ‘evolution’, and how are we to know?
In this paper I explore the necessary criteria for a generalized theory of evolution that will apply beyond the biological sciences and enable a cohesive account of diverse phenomenological observations that appear prima facie to follow evolutionary processes. In order to adequately provide an evolutionary account of candidate processes external to biology it is necessary to uncouple the functional process of evolution qua ‘evolution’ from that very medium within which it was first understood – biology. Evolution as a process must therefore be defined in terms of the functional characteristics that govern the process, independent from the medium or substrate within which that process occurs.
To do this we must draw upon our knowledge of biological evolution while being careful not to confuse the particular details of the substrate with the functional characteristics of the process itself – not an easy task when only one instantiation of the evolutionary process is well understood. It is as if we were being asked to extrapolate a theory of fluid dynamics from studying only liquid water. Yet just as fluid dynamics can apply to different forms (e.g. gases, oils, plasma, etc.) that are composed of different substances (e.g. liquid nitrogen, mercury, ethanol, etc.) so too there is no reason to suppose that the evolutionary process itself need be tied to the particulars of biology. In fact evolutionary theory seems to be committed to the necessity of pre-biotic processes of chemical evolution if it wishes to provide a coherent and internally consistent naturalistic account of the origin of life that avoids the inexplicable evolutionary leaps known as saltationism.
Maynard Smith’s account of the pre-biotic origins of life in a purely chemical evolutionary phase provide a theoretical basis for a generalized evolutionary theory. If we are to reject saltationism and intelligent design then evolutionary theory seems indeed to be committed to non-biological manifestations of the evolutionary process, and these different functional forms are not merely analogous to the evolutionary process in biology, but are in fact functional instantiations of more broadly applicable principles.
My aim then is to investigate a general theory of evolution that applies to any and all contexts. However such a task is well beyond the scope of this paper, and as a consequence I will limit my discussion primarily to that of cultural evolution, as this is the area that has received considerable recent attention. I contend that before a coherent evolutionary account of human cultural or behavioural traits can be successfully advanced – regardless of what form that account may eventually take – a comprehensive, functional account of the essential elements of ‘evolution’ must be described. Such principles of generalized evolutionary theory can then be applied to a host of non-biological contexts where evolutionary processes appear to occur, and in the process we will undoubtedly learn something essential about questions relating to the nature, origin and development of life on Earth.
Application of Evolutionary Theory to Human Culture
Evolutionary theory developed out of the study of biological phenomena, and it is of course not surprising then that evolutionary theory has been intimately tied to the details of biology. However the past few decades have seen increasing attention paid to the application of evolutionary theory to the context of human behaviour and culture. Researchers, theorists and philosophers have called attention to patterns in various realms of study that appear to display key characteristics of evolution: Popper, E.O. Wilson, Dawkins, Dennett, Skyrms, Axelrod, Ruse, Richerson, Boyd, Tooby and Cosmides, Pinker, Buss and many others have made various attempts to apply evolutionary theory to understanding human behaviour and culture in fields such as sociobiology, evolutionary psychology, evolutionary epistemology, evolutionary ethics and memetics, to name but a few. Dennett has famously gone so far as to describe Darwinism as a “universal acid.” Some of these programs have met with more acceptance than others, however all remain controversial. A central problem is how much can biology – and therefore by extension biological evolution – account for observed phenomenon within human behaviour and culture?
To answer this question we need to examine the sorts of explanations that evolutionary theory is capable of deploying. Clearly biology plays a vital role in setting the parameters of what expressions of culture and behaviour are possible, but how can evolutionary theory rooted in genes begin to offer explanations for why some cultures bury their dead while others burn them, as the problem of moral relativism classically posed by Herodotus?
The Problem of Specificity
Such questions highlight what Allan Gewirth calls the problem of specificity. Gewirth deploys his objection primarily against the evolutionary ethics of Michael Ruse, but versions of his criticism cut against any project that seeks to derive explanatory power from evolutionary theory rooted in biology. Gewirth demonstrates there is a critical gap in what such theories can actually explain in their attempt to derive moral facts from evolutionary explanations.
Difficulties arise when it becomes clear that natural selection can produce biological adaptations in favour of aggression, violence, theft and other anti-social behaviours just as readily as it does for altruism and cooperation. How then is evolutionary theory at the biological level to differentiate the truth of moral or immoral claims? While biological evolution may provide necessary conditions for moral truth (eg. a moral proposition must be contained in language, which requires a brain, which requires a host of necessary biological adaptations) it can not provide sufficient causal explanations at the level of biological or genetic evolution; biological evolution is not sufficiently specific to normatively differentiate between the possible versions of right and wrong behaviour.
Gewirth’s objection raises serious impediments against all attempts to apply biologically rooted evolutionary explanations to culturally diverse phenomena. An appeal to biological predispositions will generate little or no traction on questions of cultural diversity because such an explanation would have to demonstrate a significant hereditary component to diverse cultural phenomena. It is of course ridiculous to suggest that the behaviour of “dancing waltz” or “dancing hip-hop” are phenotypes coded for in the genes by different alleles. Clearly any explanation of why some people dance one style and not another does not reside in an appeal to biological evolution.
Yet why then do many phenomena seem to demonstrate processes that prima facie appear evolutionary in nature, such as when grandma’s apple pie recipe gets better and better over the years, or “evolves” into something entirely new – a delicious rhubarb meringue pie perhaps?
At best biologically rooted evolution can offer only necessary but not sufficient causes to questions such as these. To see this clearly we need to recall in more detail what we mean by a causal explanation. If we seek to understand the causes of a house fire we can say that the fire was caused by the oxidization of gasoline in the immediate presence of combustible furniture. The presence of gasoline near combustible furniture is a necessary condition of that particular fire, however it is not sufficient to explain why the fire happened. A complete explanation – a sufficient explanation – of the fire would also require an account of how the combustion process began, in this case the striking of a match by an arsonist in the presence of the gasoline. It is obvious that any purported causal explanation of the fire that failed to highlight the central role of the lit match applied by the arsonist to the gasoline would have failed to provide the salient sufficient cause of the fire. Such an analysis would suffer from a lack of explanatory specificity of the variety proposed by Gewirth; it is true that rapid chain-reaction oxidation is a cause at the chemical level, but the chemical level of causation is not the level that is explanatorily salient in this particular case.
Similarly, the evolutionary process shaping the brain is a necessary and vital aspect for any explanation of human behaviour, however it can not – on its own – offer a sufficiently specific account of why some behaviours occur (eg. dancing waltz) and not others (eg. dancing hip hop) in a particular instantiation given a particular environmental context. Such sufficient causes would require an additional level of explanation based upon analysis appropriate to the level of specificity required to produce the sufficient cause. In the case of the arson fire it will require an analysis at something resembling the level of criminal psychology.
An account of human cultural behaviour that is based upon evolutionary principles in some form is needed for a sufficient and salient causal account of where grandma’s rhubarb meringue pie “came from”. However the appropriate level of analysis necessary to provide sufficient salient causes will vary: in some rare cases a biological/genetic account will be sufficient (as perhaps with rooting behaviour in infants), in others an account at the level of social or cultural dynamics will be dominantly salient (eg. why hip hop and not waltz), while still other cases will require a complex web of interacting necessary causes at many levels of analysis (biochemical, cultural, cognitive, behavioural, etc.) no one of which can be construed as salient alone, and only taken together producing a sufficient explanation of the observed phenomenon (eg. why grandma’s apple rhubarb pie is so prevalent and popular in the family but not in the wider community).
Clearly most individual behaviour is not coded in the genes. Human culture is a complex aggregate of human behavioural interaction, and if the behaviour of an individual is not coded in the genes then it is transparently ridiculous that large scale aggregates of human behaviour – in the form of culture – can be biologically determined. What then should we make of research in evolutionary psychology showing a species-wide human aversion to incest, or increased likelihood of infanticide by step-fathers, for instance?
At best genes provide necessary parameters that constrain or shape human behaviour. Those research programs that seek to provide salient sufficient accounts of human cultural or behavioural patterns through an application of evolutionary theory require a generalized evolutionary theory that can operate at levels of abstraction not dependent upon biology. Isolating the necessary functional characteristics of an evolutionary process will lend insight to prominent questions within the philosophy of biology and will powerfully shape the growing application of Darwinian thinking in other spheres.
Higher-Order Evolution and Gewirth’s Specificity Problem
While the problem of specificity is a significant stumbling block for any project that seeks to tie aspects of human behaviour or culture to biologically based evolutionary processes, it also suggests a solution posed by the puzzle of evolving pie recipes and other examples of apparent cultural evolution. Various non-biological phenomena may operate according to independent evolutionary principles, thus creating a hierarchy of abstraction between first- and second-order evolutionary processes. For this model to meet Gewirth’s specificity challenge it would need to provide evolutionary details that are at least partially independent of lower level biological processes.
For example, one could conceivably provide the following evolutionary account for the development of grandma’s apple rhubarb pie recipe that is internally independent of biological evolution:
Her “famous” apple pie recipe is subjected to social selection pressures in the form of praise and approval. The pie pattern is replicated each time a new pie is baked based upon her recipe, regardless if the replicating agent is grandma herself, one of the grandkids learning to bake, or someone from the bridge club who got their filthy hands on her “famous” recipe.
If a replicating agent changes the template – perhaps by adding some extra rhubarb that was “laying around going to waste” – then a ‘mutation’ is formed and selection pressures will determine the success of the new form. The pie may not ‘turn out’ properly in the oven, leading to a failed mess that does not even deserve the name ‘pie’ and gets culled to the garbage before it is tasted. Or it may ‘turn out’ but taste horrible, smell bad or in some other way receive strong selection pressures that also cull it to the garbage. Or perhaps the pie will be welcomed and praised, receiving considerable approval as tasting even better than the original – such an outcome could well lead to a permanent modification of the recipe itself, in which case future “apple rhubarb” pies will bear the phenotype traits of the mutant strain of pie.
Such an account of the ‘evolution’ of apple rhubarb pie employs the functional form of an evolutionary process but operates on a higher-order level of abstraction in which biological mechanisms are not the salient factors at work. We may call this level of abstraction “cultural evolution,” or provide some other suitable moniker to distinguish it from biological evolution. Whatever we call it we must be clear that the salient processes governing the evolutionary functions do not refer to the replication and lineage of some biological entity such as DNA but to stable patterns of culture.
When considering such a higher-order evolutionary account as caricatured above it is important to remember that first-order evolutionary processes will necessarily constrain and in many ways direct the higher-order evolutionary processes. Making a recipe requires memory and the ability to write and read – clear products of a brain shaped by biological evolution; dyslexics may well produce quite a different pie from that intended by grandma. Taste is constrained by what the taste-buds are capable of sensing. If the pie contains toxic substances that make the recipient sick this will be governed by first-order biological processes. However within the parameters constrained by biological level first-order selection is a vast terrain of potential second-order “evolutionary space” within which higher-order evolutionary processes can shape patterns of human behaviour and culture.
What is ‘Evolution’?
In advocating for a higher-order evolutionary analysis of cultural phenomenon I have focused on the need for a generalized evolutionary theory functionally independent of the peculiarities of biology. I now wish to propose the following functional definition of ‘evolution’, with the goal of capturing the essential elements that shall distinguish all true evolutionary processes, regardless of the substrate within which they manifest:
It is beyond the scope of the present paper to defend all of the elements of the definition I have here proposed. Instead I will direct my current discussion towards an analysis of the goal of evolutionary theory and will defend the principle of adaptive complexity as the most salient core property of evolution that functionally distinguishes evolutionary from non-evolutionary processes.
In his paper entitled “Universal Darwinism” Richard Dawkins sets out to advance a universal theory of evolution applicable to all forms of life, wherever they may reside in the cosmos. While he does not specifically attempt to develop abstract principles of evolution that can apply to non-biotic substrates he does provide us with a useful starting point by abstracting principles of evolution away from purely terrestrial biology and into the realm of what he calls ‘evolutionary exobiology’. By asking how extraterrestrial life might theoretically evolve he is required to disentangle the idiosyncratic details of terrestrial biology from the functional principles that define ‘evolution’.
At the root of his functional definition Dawkins follows John Maynard Smith in highlighting adaptive complexity as the explanatory goal of evolutionary theory and, significantly, the key diagnostic principle of what constitutes ‘life’ itself. “The main task of any theory of evolution is to explain adaptive complexity, i.e. to explain the same set of facts which Paley used as evidence of a Creator.”
The question of just what constitutes life elsewhere in the universe – where the basic biochemical components may be radically different from our own – is far from a trivial question, as the Viking spacecraft demonstrated when they landed on Mars and ran experiments to detect alien life. Interestingly Dawkins abstracts the definition of ‘life’ through a functional interpretation of evolutionary processes – if an entity displays properties that indicate adaptive complexity then he contends that entity is either alive, a relic of life, or an artefact of something that was alive. In so doing he has given us a useful start to our functionally generalized definition of evolution.
In advancing adaptive complexity as the defining characteristic of evolution Dawkins argues that evolution as an explanatory theory is only of value if we are confronted with adaptive complexity. Such an approach grapples directly with the question of saltationism that underlies many of the debates in philosophy of biology, from Stephen J. Gould’s ‘punctuated equilibrium’ to Michael Behe’s ‘irreducible complexity’ arguments for intelligent design theory. The debate concerning ‘macro-mutations’ or saltationary jumps in evolutionary history extends back to debates between Darwin and Alfred Russell Wallace. Such issues go to the heart of evolutionary theory itself.
For Dawkins the key factor is one of probability – how likely is a particular change to occur through random chance alone? Adaptive complexity can only arise through a process of differential selection compounded over time. As such evolution properly understood is driven only by the selective retention of randomly occurring changes – if a phenomenon fails this criterion then it is not evolution. Small changes are far more likely to occur than large changes, particularly large numbers of changes that occur simultaneously. Calculating probabilities for such things as random mutations is no simple task, however it is helpful to at least distinguish functional principles governing the process.
Changes must be small and incremental, lest they become so improbable as to effectively be impossible. However even very improbable changes may occur on occasion, given the vast periods of time which evolutionary change can operate in and the ability of selection to retain advantageous changes when they do occur. Thus, dramatic and complex changes that are retained by selection pressure may occur gradually through a process of cumulative change, whereas such dramatic and complex changes are vanishingly less likely if construed as happening simultaneously or as a single event.
The classic example here deployed by all sides of the debate is the evolution of the eye, advanced by fundamentalists and intelligent design advocates from Paley onward, and also featured prominently in Darwin’s The Origin of Species. The eye is clearly adaptive, in the sense that it is highly tailored to perform a certain function in accordance with the laws of optics that are imposed by the external environment. It is also vanishingly improbable to propose that the eye just “formed itself” by random chance, as fundamentalists rightly assert. How then to explain such a clear case of adaptive complexity? Fundamentalists argue that “only” a designer could be responsible, however evolutionary theory proposes a more likely process with a series of small, incremental steps, accumulating over countless ages, each step providing a selective increase in adaptive advantage and complexity.
It is then a simple matter to take such principles and apply them to non-biological context, and from there derive the basis for our functional account of evolutionary theory. If we return to pie recipes as a guiding example, how can we explain the existence of lemon meringue pie today? What was to stop a member of Homo sapien sapiens from inventing lemon meringue pie during the Upper Paleolithic era?
Lemon meringue pie is a highly tasty treat that generates strong behaviour reinforcement. By this virtue it produces strong selective pressures to retain and replicate such recipe patterns within human culture and therefore we may consider it to be a well adapted entity filling a cultural niche. But what of the question of complexity?
Such a dessert showing up during the Upper Paleolithic seems vanishingly improbable. There are many numerous components necessary to make a lemon meringue pie, and most of these are difficult to notice for us today because we take them for granted. We first must assume the development of flour as a baking ingredient, cream of tarter as a binding agent, or the best means of producing pie crusts. Each necessitates long periods of development.
The meringue itself seems like a highly counter-intuitive and unlikely product that requires significant independent development. We must know how to separate and beat egg whites, and must know how to cultivate and process caster sugar and cream of tarter. All together, the act of producing a lemon meringue pie is positively overloaded with a succession of small baking innovations that have accumulated over time, and which are retained and propagated through the processes of imitation and social teaching in which human beings uniquely excel.
Our Homo sapien sapien ancestors in the Upper Paleolithic would have been hopelessly incapable of producing a lemon meringue pie because it is deeply improbable that all the necessary baking innovations could have arisen at once. Lemon meringue is a highly complex pattern, and therefore highly unlikely to arise fully developed in a sudden leap.
It is even more unlikely that biological evolution can explain this observation, given that there is little biological difference between modern H. sapiens and our Upper Paleolithic ancestors. No one would argue that pie-making ability is a phenotypic trait coded by the genes.
How then should we explain the existence of such a dessert in today’s world? Did the recipe for lemon meringue pie – including the notion of how to make meringue and how to make a pie crust from “scratch” – just jump into some ingenious baker’s head many hundreds of years ago? I am unaware of any factual historical data concerning the origin of lemon meringue pie, but such a proposal seems highly improbable in precisely the same way that it is unlikely for the eye to jump into existence by random chance all at once in one generation.
Instead we must seek another explanation for how lemon meringue pie came into existence. Our pie is an example of adaptive complexity, and our alternate explanation must be an evolutionary explanation. I could easily substitute any other product of technological development for our pie example: the steel of Spanish swords, the internal combustion engine, sailing ships, the plow, Euclidian geometry, agricultural irrigation systems, space flight, firearms, smelting, quantum mechanics… all of these entities are adaptively complex patterns that did not leap into existence in one highly improbable step but were instead the culmination of a series of small and successively more adaptive improvements.
If a medieval Spanish smith tried a technique for forging steel that produced a better sword he remembered it and taught it to his apprentices. If the technique failed the experiment was discarded and forgotten. Over time a succession of such innovations lead to the technological improvement of Spanish weapon smithing by a process of differential selection. Notice that this second-order evolutionary process is completely divorced from whether or not the cultural pattern in question had a positive, negative or entirely negligible impact upon the underlying biological fitness of the first-order evolutionary process. Strong Spanish swords may increase biological fitness by increasing the likelihood of success in battle, or it may decrease fitness by increasing the potential appeal for invasion and subjugation of societies containing such technology. Or it may act like our rhubarb meringue pie and merely be an oddity with no appreciable effects upon biological fitness – except perhaps the ‘fitness’ around the waistline.
I must hasten to add that such a process is not limited to technological innovation, which is merely the case study I have chosen to follow. This process of cumulative selection can be deployed to offer explanations for observed moral phenomena, including the near-universality of adaptively complex ethical norms such as the ‘golden rule’ or taboos against incest and cannibalism. It can be deployed to explain the successful ‘fit’ of scientific theories to the world. Computer viruses may display similar patterns, as may dances, fashion, word etymologies, music, religion or many other cultural patterns. Such a model is generally applicable across human culture and can offer precisely the sort of second-order evolutionary account of human behavioural phenomena that is needed to overcome Gewirth’s problem of specificity. However we must be careful not to be too cavalier in our application of such a model, for it ought to be clear that not every trait arose by adaptation through differential selection.
Adaptationism and Genetic Drift
How then do we demarcate the boundaries between an evolutionary process and simple non-evolutionary change? The answer must again return to the principle of adaptive complexity. Any process that does not display the properties of adaptive complexity is by definition not ‘evolution’. Change may occur, but if it is not the product of selection pressure then it can not be adaptive, in which case the process that generated it can not be considered an evolutionary processes. Determining what traits are adaptive is no easy task in biology, and is a source of much vitriolic controversy which leads us to grapple with one of the central debates in philosophy of biology: adaptationism.
Much philosophical blood has been spilled over to what degree existing biological traits constitute products of selection pressure and hence adaptations, as opposed to mere qualities that have arisen by some other mechanism. For the purposes of developing a generalized theory of evolution I wish to sidestep the particulars of the various debates over concrete biological cases. Instead I wish to examine the process of genetic drift, a concept that has been advanced as a counter example to adaptationism within biology and will be most helpful to illuminate the boundary between true evolutionary processes and those that merely constitute some form of undirected change.
Genetic drift occurs within a reproducing population when the frequency of a particular trait changes over time by pure random chance, and hence without adaptive direction. For random chance to drive the frequency shift it is necessary that the trait in question have negligible fitness ramifications, else selection pressure would cull less fit varieties, thereby re-establishing the direction of trait frequency towards more adaptive versions. Thus, traits upon which there are weak or negligible selection pressures may experience drift. As a consequence such traits may well be complex, but will most certainly not be adapted and hence the process of drift ought not be considered evolutionary.
In biological settings genetic drift is usually only considered an ecological factor in small populations where the effects of chance variation are more able to have a lasting effect. If only a small number of individuals carry a particular trait it is far more possible for the trait to be eliminated from the gene pool due to random happenstance, whereas with a larger number it is more likely that the trait can re-establish itself in the pool from a small number of carriers, even in the event that a large percentage of the carriers are culled by chance. However for the purposes of examining genetic drift within the context of cultural evolution this need not be the case.
In order to disentangle the concept of genetic drift from the idiosyncrasies of biological factors we must describe the functional characteristics of the process in abstract form. The key principle that distinguishes the process of drift is a shift of trait frequency within the population that occurs entirely by chance; selection plays a negligible role with the result that the change of trait frequency over time occurs in a random direction. To distinguish drift in the biological context from a generalized abstract context I will therefore redesignate the generalized form of genetic drift as ‘frequency drift.’
‘Frequency drift’ may then be defined as a random change of extant trait frequency relative to the larger population of equivalent trait alternatives in the absence of selection pressure strong enough to overcome random forces and thereby direct the course of trait frequency shift in a non-random direction.
Let us return to our pie baking examples. Grandma could choose to bake her pie in a round pan and serve wedge shaped pieces, or a square pan serving square pieces. It is possible that some may dislike one method of serving versus the other, in which case selection pressure would act upon the two baking “styles”. However, the key question that must be resolved is whether the preference for one style over another is strong enough to overcome random factors.
Imagine that grandma has a very busy kitchen (she has a large extended family to bake for!) and a limited supply of baking sheets. Sometimes the square sheets are in use and so she must use the round sheets to bake her pies, and sometimes the situation is reversed. Which situation presents itself is essentially random. If her round pies are devoured, but the square pies go to waste then we may say that there is selection pressure against square pies. If this selection pressure results in grandma limiting the frequency with which she bakes square pies then we can say selection pressure has shifted the frequency of round versus square pies, and as a consequence round pies have ‘evolved’ because they are more adaptive to the fussy preferences of the grandkids.
However, if both square and round pies are eaten when they are served, we can say that there is no significant selection pressure favouring one “style” of pie shape over another. If then by random chance it happens that most of grandma’s round pie sheets disappear (perhaps donated to a niece who is moving out on her own) and replaced by square sheets the frequency of square pies may increase dramatically. Square pies would not have ‘evolved’ because squareness is not the subject of selection pressure and thereby not an adaptive trait – the propensity for square pies in the family arose merely by chance through frequency drift, not a process of ‘evolution.’
We can think of many similar examples of cultural traits where selection pressures are low. Any time we speak in common parlance about “fashion,” “preference,” “style,” “taste,” or other such words we are often indicating a situation in which choices are fickle and selection pressures are weak. Hair styles, hem lengths, musical preferences, dance styles, food tastes and a host of other cultural characteristics that are known to fluctuate randomly over time can be described as cases of ‘frequency drift’ within a cultural milieu. Such traits are not products of selection, hence they are not adaptive, and hence can not be described or explained according to evolutionary principles.
CONCLUSION
The goal of this paper has been to provide a preliminary sketch for a generalized functional account of evolutionary principles that can apply evolutionary theory to non-biological contexts. In the process I argue that Gewirth’s problem of specificity suggests the need for a second-order evolutionary analysis of cultural phenomena that display apparent evolutionary patterns. I then propose a functional definition of evolution that is founded on the notion of adaptive complexity through differential selection, and suggest the concept of ‘frequency drift’ as a process to distinguish evolutionary from non-evolutionary change.
The clear implications that can be drawn from this analysis of generalized evolutionary theory is that a great deal of cultural phenomena are likely to be non-evolutionary in nature, and thus beyond a strictly selectionist evolutionary account except in-so-far as to say that the phenomena in question arose as a consequence of random frequency drift or some other as-yet-undescribed phenomenon. This itself is not a trivial conclusion lacking in explanatory power; other fields such as quantum mechanics and chaos theory infuse random occurrence with explanatory power to great profit, and criterion are needed for the demarcation of evolutionary and non-evolutionary processes. Clearly not all change is evolutionary in nature.
However it is equally clear that a great deal of cultural change can be described and given explanatory weight through an appeal to the sort of generalized second-order evolutionary account demonstrated above. Any time a form of differential selection shifts the frequency of cultural phenomena in a particular non-random direction an evolutionary account will be explanatorily potent. The dividing line that distinguishes which cultural phenomena are evolutionary and which are not is an empirical question that can only be resolved through a case by case investigation of each phenomenon, but it is increasingly clear that a great deal of human culture is accessible to such an investigation.
BIBLIOGRAPHY
Boyd, Robert and Peter J. Richerson. The Origin and Evolution of Cultures. Oxford: Oxford University Press, 2005.
Boyd, Robert and Peter J. Richerson. Culture and the Evolutionary Process. Chicago: University of Chicago Press, 1985.
Cziko, Gary. Without Miracles: Universal Selection Theory and the Second Darwinian Revolution. Cambridge, MA: The MIT Press, 1995.
Dawkins, Richard. The Selfish Gene. Oxford: Oxford university Press, 1989.
Dawkins, Richard. “Universal Darwinism.” In Evolution from Molecules to Man by D.S. Bendall. Cambridge: Cambridge University Press, 1983, 403-25.
Dennett, Daniel C. Darwin's Dangerous Idea. New York: Touchstone, 1995.
Gewirth, Alan. “The Problem of Specificity in Evolutionary Ethics.” Biology and Philosophy I (1986): 297-305.
Maynard Smith, John and Eors Szathmary. The Major Transitions in Evolution. Oxford: W.H. Freeman and Company Limited, 1995.
Maynard Smith, John and Eors Szathmary. The Origins of Life: From the Birth of Life to the Origins of Language. Oxford: Oxford university Press, 1999.
Sterelny, Kim and Paul E. Griffiths. Sex and Death: An Introduction to Philosophy of Biology. Chicago: University of Chicago Press, 1999.
I argue that before a profitable account of evolution can be successfully applied to non-biological processes a generalized functional theory of evolution must first be developed. Biological first-order evolutionary accounts of cultural traits are unlikely to account for cultural phenomenon because of the intrinsic lack of specificity as described by Gewirth, however second-order evolutionary processes independent of biological mechanisms have the power to move beyond providing trivial necessary biological explanations. Finally, I offer a preliminary attempt to sketch a generalized functional evolutionary theory that is predicated upon the existence of adaptive complexity as a defining character of all bona fide evolutionary processes, against which I distinguish random ‘frequency shift’ as a key characteristic of non-evolutionary change.
Do evolutionary processes, strictly speaking, occur in non-biological contexts, or is ‘evolution’ purely confined to living entities? Can evolutionary processes be distinguished from the contingent details of biology and abstracted into a more generally applicable theory? Are apparent evolutionary patterns in culture truly ‘evolution’, and how are we to know?
In this paper I explore the necessary criteria for a generalized theory of evolution that will apply beyond the biological sciences and enable a cohesive account of diverse phenomenological observations that appear prima facie to follow evolutionary processes. In order to adequately provide an evolutionary account of candidate processes external to biology it is necessary to uncouple the functional process of evolution qua ‘evolution’ from that very medium within which it was first understood – biology. Evolution as a process must therefore be defined in terms of the functional characteristics that govern the process, independent from the medium or substrate within which that process occurs.
To do this we must draw upon our knowledge of biological evolution while being careful not to confuse the particular details of the substrate with the functional characteristics of the process itself – not an easy task when only one instantiation of the evolutionary process is well understood. It is as if we were being asked to extrapolate a theory of fluid dynamics from studying only liquid water. Yet just as fluid dynamics can apply to different forms (e.g. gases, oils, plasma, etc.) that are composed of different substances (e.g. liquid nitrogen, mercury, ethanol, etc.) so too there is no reason to suppose that the evolutionary process itself need be tied to the particulars of biology. In fact evolutionary theory seems to be committed to the necessity of pre-biotic processes of chemical evolution if it wishes to provide a coherent and internally consistent naturalistic account of the origin of life that avoids the inexplicable evolutionary leaps known as saltationism.
Maynard Smith’s account of the pre-biotic origins of life in a purely chemical evolutionary phase provide a theoretical basis for a generalized evolutionary theory. If we are to reject saltationism and intelligent design then evolutionary theory seems indeed to be committed to non-biological manifestations of the evolutionary process, and these different functional forms are not merely analogous to the evolutionary process in biology, but are in fact functional instantiations of more broadly applicable principles.
My aim then is to investigate a general theory of evolution that applies to any and all contexts. However such a task is well beyond the scope of this paper, and as a consequence I will limit my discussion primarily to that of cultural evolution, as this is the area that has received considerable recent attention. I contend that before a coherent evolutionary account of human cultural or behavioural traits can be successfully advanced – regardless of what form that account may eventually take – a comprehensive, functional account of the essential elements of ‘evolution’ must be described. Such principles of generalized evolutionary theory can then be applied to a host of non-biological contexts where evolutionary processes appear to occur, and in the process we will undoubtedly learn something essential about questions relating to the nature, origin and development of life on Earth.
Application of Evolutionary Theory to Human Culture
Evolutionary theory developed out of the study of biological phenomena, and it is of course not surprising then that evolutionary theory has been intimately tied to the details of biology. However the past few decades have seen increasing attention paid to the application of evolutionary theory to the context of human behaviour and culture. Researchers, theorists and philosophers have called attention to patterns in various realms of study that appear to display key characteristics of evolution: Popper, E.O. Wilson, Dawkins, Dennett, Skyrms, Axelrod, Ruse, Richerson, Boyd, Tooby and Cosmides, Pinker, Buss and many others have made various attempts to apply evolutionary theory to understanding human behaviour and culture in fields such as sociobiology, evolutionary psychology, evolutionary epistemology, evolutionary ethics and memetics, to name but a few. Dennett has famously gone so far as to describe Darwinism as a “universal acid.” Some of these programs have met with more acceptance than others, however all remain controversial. A central problem is how much can biology – and therefore by extension biological evolution – account for observed phenomenon within human behaviour and culture?
To answer this question we need to examine the sorts of explanations that evolutionary theory is capable of deploying. Clearly biology plays a vital role in setting the parameters of what expressions of culture and behaviour are possible, but how can evolutionary theory rooted in genes begin to offer explanations for why some cultures bury their dead while others burn them, as the problem of moral relativism classically posed by Herodotus?
The Problem of Specificity
Such questions highlight what Allan Gewirth calls the problem of specificity. Gewirth deploys his objection primarily against the evolutionary ethics of Michael Ruse, but versions of his criticism cut against any project that seeks to derive explanatory power from evolutionary theory rooted in biology. Gewirth demonstrates there is a critical gap in what such theories can actually explain in their attempt to derive moral facts from evolutionary explanations.
Difficulties arise when it becomes clear that natural selection can produce biological adaptations in favour of aggression, violence, theft and other anti-social behaviours just as readily as it does for altruism and cooperation. How then is evolutionary theory at the biological level to differentiate the truth of moral or immoral claims? While biological evolution may provide necessary conditions for moral truth (eg. a moral proposition must be contained in language, which requires a brain, which requires a host of necessary biological adaptations) it can not provide sufficient causal explanations at the level of biological or genetic evolution; biological evolution is not sufficiently specific to normatively differentiate between the possible versions of right and wrong behaviour.
Gewirth’s objection raises serious impediments against all attempts to apply biologically rooted evolutionary explanations to culturally diverse phenomena. An appeal to biological predispositions will generate little or no traction on questions of cultural diversity because such an explanation would have to demonstrate a significant hereditary component to diverse cultural phenomena. It is of course ridiculous to suggest that the behaviour of “dancing waltz” or “dancing hip-hop” are phenotypes coded for in the genes by different alleles. Clearly any explanation of why some people dance one style and not another does not reside in an appeal to biological evolution.
Yet why then do many phenomena seem to demonstrate processes that prima facie appear evolutionary in nature, such as when grandma’s apple pie recipe gets better and better over the years, or “evolves” into something entirely new – a delicious rhubarb meringue pie perhaps?
At best biologically rooted evolution can offer only necessary but not sufficient causes to questions such as these. To see this clearly we need to recall in more detail what we mean by a causal explanation. If we seek to understand the causes of a house fire we can say that the fire was caused by the oxidization of gasoline in the immediate presence of combustible furniture. The presence of gasoline near combustible furniture is a necessary condition of that particular fire, however it is not sufficient to explain why the fire happened. A complete explanation – a sufficient explanation – of the fire would also require an account of how the combustion process began, in this case the striking of a match by an arsonist in the presence of the gasoline. It is obvious that any purported causal explanation of the fire that failed to highlight the central role of the lit match applied by the arsonist to the gasoline would have failed to provide the salient sufficient cause of the fire. Such an analysis would suffer from a lack of explanatory specificity of the variety proposed by Gewirth; it is true that rapid chain-reaction oxidation is a cause at the chemical level, but the chemical level of causation is not the level that is explanatorily salient in this particular case.
Similarly, the evolutionary process shaping the brain is a necessary and vital aspect for any explanation of human behaviour, however it can not – on its own – offer a sufficiently specific account of why some behaviours occur (eg. dancing waltz) and not others (eg. dancing hip hop) in a particular instantiation given a particular environmental context. Such sufficient causes would require an additional level of explanation based upon analysis appropriate to the level of specificity required to produce the sufficient cause. In the case of the arson fire it will require an analysis at something resembling the level of criminal psychology.
An account of human cultural behaviour that is based upon evolutionary principles in some form is needed for a sufficient and salient causal account of where grandma’s rhubarb meringue pie “came from”. However the appropriate level of analysis necessary to provide sufficient salient causes will vary: in some rare cases a biological/genetic account will be sufficient (as perhaps with rooting behaviour in infants), in others an account at the level of social or cultural dynamics will be dominantly salient (eg. why hip hop and not waltz), while still other cases will require a complex web of interacting necessary causes at many levels of analysis (biochemical, cultural, cognitive, behavioural, etc.) no one of which can be construed as salient alone, and only taken together producing a sufficient explanation of the observed phenomenon (eg. why grandma’s apple rhubarb pie is so prevalent and popular in the family but not in the wider community).
Clearly most individual behaviour is not coded in the genes. Human culture is a complex aggregate of human behavioural interaction, and if the behaviour of an individual is not coded in the genes then it is transparently ridiculous that large scale aggregates of human behaviour – in the form of culture – can be biologically determined. What then should we make of research in evolutionary psychology showing a species-wide human aversion to incest, or increased likelihood of infanticide by step-fathers, for instance?
At best genes provide necessary parameters that constrain or shape human behaviour. Those research programs that seek to provide salient sufficient accounts of human cultural or behavioural patterns through an application of evolutionary theory require a generalized evolutionary theory that can operate at levels of abstraction not dependent upon biology. Isolating the necessary functional characteristics of an evolutionary process will lend insight to prominent questions within the philosophy of biology and will powerfully shape the growing application of Darwinian thinking in other spheres.
Higher-Order Evolution and Gewirth’s Specificity Problem
While the problem of specificity is a significant stumbling block for any project that seeks to tie aspects of human behaviour or culture to biologically based evolutionary processes, it also suggests a solution posed by the puzzle of evolving pie recipes and other examples of apparent cultural evolution. Various non-biological phenomena may operate according to independent evolutionary principles, thus creating a hierarchy of abstraction between first- and second-order evolutionary processes. For this model to meet Gewirth’s specificity challenge it would need to provide evolutionary details that are at least partially independent of lower level biological processes.
For example, one could conceivably provide the following evolutionary account for the development of grandma’s apple rhubarb pie recipe that is internally independent of biological evolution:
Her “famous” apple pie recipe is subjected to social selection pressures in the form of praise and approval. The pie pattern is replicated each time a new pie is baked based upon her recipe, regardless if the replicating agent is grandma herself, one of the grandkids learning to bake, or someone from the bridge club who got their filthy hands on her “famous” recipe.
If a replicating agent changes the template – perhaps by adding some extra rhubarb that was “laying around going to waste” – then a ‘mutation’ is formed and selection pressures will determine the success of the new form. The pie may not ‘turn out’ properly in the oven, leading to a failed mess that does not even deserve the name ‘pie’ and gets culled to the garbage before it is tasted. Or it may ‘turn out’ but taste horrible, smell bad or in some other way receive strong selection pressures that also cull it to the garbage. Or perhaps the pie will be welcomed and praised, receiving considerable approval as tasting even better than the original – such an outcome could well lead to a permanent modification of the recipe itself, in which case future “apple rhubarb” pies will bear the phenotype traits of the mutant strain of pie.
Such an account of the ‘evolution’ of apple rhubarb pie employs the functional form of an evolutionary process but operates on a higher-order level of abstraction in which biological mechanisms are not the salient factors at work. We may call this level of abstraction “cultural evolution,” or provide some other suitable moniker to distinguish it from biological evolution. Whatever we call it we must be clear that the salient processes governing the evolutionary functions do not refer to the replication and lineage of some biological entity such as DNA but to stable patterns of culture.
When considering such a higher-order evolutionary account as caricatured above it is important to remember that first-order evolutionary processes will necessarily constrain and in many ways direct the higher-order evolutionary processes. Making a recipe requires memory and the ability to write and read – clear products of a brain shaped by biological evolution; dyslexics may well produce quite a different pie from that intended by grandma. Taste is constrained by what the taste-buds are capable of sensing. If the pie contains toxic substances that make the recipient sick this will be governed by first-order biological processes. However within the parameters constrained by biological level first-order selection is a vast terrain of potential second-order “evolutionary space” within which higher-order evolutionary processes can shape patterns of human behaviour and culture.
What is ‘Evolution’?
In advocating for a higher-order evolutionary analysis of cultural phenomenon I have focused on the need for a generalized evolutionary theory functionally independent of the peculiarities of biology. I now wish to propose the following functional definition of ‘evolution’, with the goal of capturing the essential elements that shall distinguish all true evolutionary processes, regardless of the substrate within which they manifest:
Evolution is the frequency shift of reproducing stable patterns caused by differential selection that explains adaptive complexity too improbable to come about at random by a single occurrence.
It is beyond the scope of the present paper to defend all of the elements of the definition I have here proposed. Instead I will direct my current discussion towards an analysis of the goal of evolutionary theory and will defend the principle of adaptive complexity as the most salient core property of evolution that functionally distinguishes evolutionary from non-evolutionary processes.
In his paper entitled “Universal Darwinism” Richard Dawkins sets out to advance a universal theory of evolution applicable to all forms of life, wherever they may reside in the cosmos. While he does not specifically attempt to develop abstract principles of evolution that can apply to non-biotic substrates he does provide us with a useful starting point by abstracting principles of evolution away from purely terrestrial biology and into the realm of what he calls ‘evolutionary exobiology’. By asking how extraterrestrial life might theoretically evolve he is required to disentangle the idiosyncratic details of terrestrial biology from the functional principles that define ‘evolution’.
At the root of his functional definition Dawkins follows John Maynard Smith in highlighting adaptive complexity as the explanatory goal of evolutionary theory and, significantly, the key diagnostic principle of what constitutes ‘life’ itself. “The main task of any theory of evolution is to explain adaptive complexity, i.e. to explain the same set of facts which Paley used as evidence of a Creator.”
The question of just what constitutes life elsewhere in the universe – where the basic biochemical components may be radically different from our own – is far from a trivial question, as the Viking spacecraft demonstrated when they landed on Mars and ran experiments to detect alien life. Interestingly Dawkins abstracts the definition of ‘life’ through a functional interpretation of evolutionary processes – if an entity displays properties that indicate adaptive complexity then he contends that entity is either alive, a relic of life, or an artefact of something that was alive. In so doing he has given us a useful start to our functionally generalized definition of evolution.
In advancing adaptive complexity as the defining characteristic of evolution Dawkins argues that evolution as an explanatory theory is only of value if we are confronted with adaptive complexity. Such an approach grapples directly with the question of saltationism that underlies many of the debates in philosophy of biology, from Stephen J. Gould’s ‘punctuated equilibrium’ to Michael Behe’s ‘irreducible complexity’ arguments for intelligent design theory. The debate concerning ‘macro-mutations’ or saltationary jumps in evolutionary history extends back to debates between Darwin and Alfred Russell Wallace. Such issues go to the heart of evolutionary theory itself.
For Dawkins the key factor is one of probability – how likely is a particular change to occur through random chance alone? Adaptive complexity can only arise through a process of differential selection compounded over time. As such evolution properly understood is driven only by the selective retention of randomly occurring changes – if a phenomenon fails this criterion then it is not evolution. Small changes are far more likely to occur than large changes, particularly large numbers of changes that occur simultaneously. Calculating probabilities for such things as random mutations is no simple task, however it is helpful to at least distinguish functional principles governing the process.
Changes must be small and incremental, lest they become so improbable as to effectively be impossible. However even very improbable changes may occur on occasion, given the vast periods of time which evolutionary change can operate in and the ability of selection to retain advantageous changes when they do occur. Thus, dramatic and complex changes that are retained by selection pressure may occur gradually through a process of cumulative change, whereas such dramatic and complex changes are vanishingly less likely if construed as happening simultaneously or as a single event.
The classic example here deployed by all sides of the debate is the evolution of the eye, advanced by fundamentalists and intelligent design advocates from Paley onward, and also featured prominently in Darwin’s The Origin of Species. The eye is clearly adaptive, in the sense that it is highly tailored to perform a certain function in accordance with the laws of optics that are imposed by the external environment. It is also vanishingly improbable to propose that the eye just “formed itself” by random chance, as fundamentalists rightly assert. How then to explain such a clear case of adaptive complexity? Fundamentalists argue that “only” a designer could be responsible, however evolutionary theory proposes a more likely process with a series of small, incremental steps, accumulating over countless ages, each step providing a selective increase in adaptive advantage and complexity.
It is then a simple matter to take such principles and apply them to non-biological context, and from there derive the basis for our functional account of evolutionary theory. If we return to pie recipes as a guiding example, how can we explain the existence of lemon meringue pie today? What was to stop a member of Homo sapien sapiens from inventing lemon meringue pie during the Upper Paleolithic era?
Lemon meringue pie is a highly tasty treat that generates strong behaviour reinforcement. By this virtue it produces strong selective pressures to retain and replicate such recipe patterns within human culture and therefore we may consider it to be a well adapted entity filling a cultural niche. But what of the question of complexity?
Such a dessert showing up during the Upper Paleolithic seems vanishingly improbable. There are many numerous components necessary to make a lemon meringue pie, and most of these are difficult to notice for us today because we take them for granted. We first must assume the development of flour as a baking ingredient, cream of tarter as a binding agent, or the best means of producing pie crusts. Each necessitates long periods of development.
The meringue itself seems like a highly counter-intuitive and unlikely product that requires significant independent development. We must know how to separate and beat egg whites, and must know how to cultivate and process caster sugar and cream of tarter. All together, the act of producing a lemon meringue pie is positively overloaded with a succession of small baking innovations that have accumulated over time, and which are retained and propagated through the processes of imitation and social teaching in which human beings uniquely excel.
Our Homo sapien sapien ancestors in the Upper Paleolithic would have been hopelessly incapable of producing a lemon meringue pie because it is deeply improbable that all the necessary baking innovations could have arisen at once. Lemon meringue is a highly complex pattern, and therefore highly unlikely to arise fully developed in a sudden leap.
It is even more unlikely that biological evolution can explain this observation, given that there is little biological difference between modern H. sapiens and our Upper Paleolithic ancestors. No one would argue that pie-making ability is a phenotypic trait coded by the genes.
How then should we explain the existence of such a dessert in today’s world? Did the recipe for lemon meringue pie – including the notion of how to make meringue and how to make a pie crust from “scratch” – just jump into some ingenious baker’s head many hundreds of years ago? I am unaware of any factual historical data concerning the origin of lemon meringue pie, but such a proposal seems highly improbable in precisely the same way that it is unlikely for the eye to jump into existence by random chance all at once in one generation.
Instead we must seek another explanation for how lemon meringue pie came into existence. Our pie is an example of adaptive complexity, and our alternate explanation must be an evolutionary explanation. I could easily substitute any other product of technological development for our pie example: the steel of Spanish swords, the internal combustion engine, sailing ships, the plow, Euclidian geometry, agricultural irrigation systems, space flight, firearms, smelting, quantum mechanics… all of these entities are adaptively complex patterns that did not leap into existence in one highly improbable step but were instead the culmination of a series of small and successively more adaptive improvements.
If a medieval Spanish smith tried a technique for forging steel that produced a better sword he remembered it and taught it to his apprentices. If the technique failed the experiment was discarded and forgotten. Over time a succession of such innovations lead to the technological improvement of Spanish weapon smithing by a process of differential selection. Notice that this second-order evolutionary process is completely divorced from whether or not the cultural pattern in question had a positive, negative or entirely negligible impact upon the underlying biological fitness of the first-order evolutionary process. Strong Spanish swords may increase biological fitness by increasing the likelihood of success in battle, or it may decrease fitness by increasing the potential appeal for invasion and subjugation of societies containing such technology. Or it may act like our rhubarb meringue pie and merely be an oddity with no appreciable effects upon biological fitness – except perhaps the ‘fitness’ around the waistline.
I must hasten to add that such a process is not limited to technological innovation, which is merely the case study I have chosen to follow. This process of cumulative selection can be deployed to offer explanations for observed moral phenomena, including the near-universality of adaptively complex ethical norms such as the ‘golden rule’ or taboos against incest and cannibalism. It can be deployed to explain the successful ‘fit’ of scientific theories to the world. Computer viruses may display similar patterns, as may dances, fashion, word etymologies, music, religion or many other cultural patterns. Such a model is generally applicable across human culture and can offer precisely the sort of second-order evolutionary account of human behavioural phenomena that is needed to overcome Gewirth’s problem of specificity. However we must be careful not to be too cavalier in our application of such a model, for it ought to be clear that not every trait arose by adaptation through differential selection.
Adaptationism and Genetic Drift
How then do we demarcate the boundaries between an evolutionary process and simple non-evolutionary change? The answer must again return to the principle of adaptive complexity. Any process that does not display the properties of adaptive complexity is by definition not ‘evolution’. Change may occur, but if it is not the product of selection pressure then it can not be adaptive, in which case the process that generated it can not be considered an evolutionary processes. Determining what traits are adaptive is no easy task in biology, and is a source of much vitriolic controversy which leads us to grapple with one of the central debates in philosophy of biology: adaptationism.
Much philosophical blood has been spilled over to what degree existing biological traits constitute products of selection pressure and hence adaptations, as opposed to mere qualities that have arisen by some other mechanism. For the purposes of developing a generalized theory of evolution I wish to sidestep the particulars of the various debates over concrete biological cases. Instead I wish to examine the process of genetic drift, a concept that has been advanced as a counter example to adaptationism within biology and will be most helpful to illuminate the boundary between true evolutionary processes and those that merely constitute some form of undirected change.
Genetic drift occurs within a reproducing population when the frequency of a particular trait changes over time by pure random chance, and hence without adaptive direction. For random chance to drive the frequency shift it is necessary that the trait in question have negligible fitness ramifications, else selection pressure would cull less fit varieties, thereby re-establishing the direction of trait frequency towards more adaptive versions. Thus, traits upon which there are weak or negligible selection pressures may experience drift. As a consequence such traits may well be complex, but will most certainly not be adapted and hence the process of drift ought not be considered evolutionary.
In biological settings genetic drift is usually only considered an ecological factor in small populations where the effects of chance variation are more able to have a lasting effect. If only a small number of individuals carry a particular trait it is far more possible for the trait to be eliminated from the gene pool due to random happenstance, whereas with a larger number it is more likely that the trait can re-establish itself in the pool from a small number of carriers, even in the event that a large percentage of the carriers are culled by chance. However for the purposes of examining genetic drift within the context of cultural evolution this need not be the case.
In order to disentangle the concept of genetic drift from the idiosyncrasies of biological factors we must describe the functional characteristics of the process in abstract form. The key principle that distinguishes the process of drift is a shift of trait frequency within the population that occurs entirely by chance; selection plays a negligible role with the result that the change of trait frequency over time occurs in a random direction. To distinguish drift in the biological context from a generalized abstract context I will therefore redesignate the generalized form of genetic drift as ‘frequency drift.’
‘Frequency drift’ may then be defined as a random change of extant trait frequency relative to the larger population of equivalent trait alternatives in the absence of selection pressure strong enough to overcome random forces and thereby direct the course of trait frequency shift in a non-random direction.
Let us return to our pie baking examples. Grandma could choose to bake her pie in a round pan and serve wedge shaped pieces, or a square pan serving square pieces. It is possible that some may dislike one method of serving versus the other, in which case selection pressure would act upon the two baking “styles”. However, the key question that must be resolved is whether the preference for one style over another is strong enough to overcome random factors.
Imagine that grandma has a very busy kitchen (she has a large extended family to bake for!) and a limited supply of baking sheets. Sometimes the square sheets are in use and so she must use the round sheets to bake her pies, and sometimes the situation is reversed. Which situation presents itself is essentially random. If her round pies are devoured, but the square pies go to waste then we may say that there is selection pressure against square pies. If this selection pressure results in grandma limiting the frequency with which she bakes square pies then we can say selection pressure has shifted the frequency of round versus square pies, and as a consequence round pies have ‘evolved’ because they are more adaptive to the fussy preferences of the grandkids.
However, if both square and round pies are eaten when they are served, we can say that there is no significant selection pressure favouring one “style” of pie shape over another. If then by random chance it happens that most of grandma’s round pie sheets disappear (perhaps donated to a niece who is moving out on her own) and replaced by square sheets the frequency of square pies may increase dramatically. Square pies would not have ‘evolved’ because squareness is not the subject of selection pressure and thereby not an adaptive trait – the propensity for square pies in the family arose merely by chance through frequency drift, not a process of ‘evolution.’
We can think of many similar examples of cultural traits where selection pressures are low. Any time we speak in common parlance about “fashion,” “preference,” “style,” “taste,” or other such words we are often indicating a situation in which choices are fickle and selection pressures are weak. Hair styles, hem lengths, musical preferences, dance styles, food tastes and a host of other cultural characteristics that are known to fluctuate randomly over time can be described as cases of ‘frequency drift’ within a cultural milieu. Such traits are not products of selection, hence they are not adaptive, and hence can not be described or explained according to evolutionary principles.
CONCLUSION
The goal of this paper has been to provide a preliminary sketch for a generalized functional account of evolutionary principles that can apply evolutionary theory to non-biological contexts. In the process I argue that Gewirth’s problem of specificity suggests the need for a second-order evolutionary analysis of cultural phenomena that display apparent evolutionary patterns. I then propose a functional definition of evolution that is founded on the notion of adaptive complexity through differential selection, and suggest the concept of ‘frequency drift’ as a process to distinguish evolutionary from non-evolutionary change.
The clear implications that can be drawn from this analysis of generalized evolutionary theory is that a great deal of cultural phenomena are likely to be non-evolutionary in nature, and thus beyond a strictly selectionist evolutionary account except in-so-far as to say that the phenomena in question arose as a consequence of random frequency drift or some other as-yet-undescribed phenomenon. This itself is not a trivial conclusion lacking in explanatory power; other fields such as quantum mechanics and chaos theory infuse random occurrence with explanatory power to great profit, and criterion are needed for the demarcation of evolutionary and non-evolutionary processes. Clearly not all change is evolutionary in nature.
However it is equally clear that a great deal of cultural change can be described and given explanatory weight through an appeal to the sort of generalized second-order evolutionary account demonstrated above. Any time a form of differential selection shifts the frequency of cultural phenomena in a particular non-random direction an evolutionary account will be explanatorily potent. The dividing line that distinguishes which cultural phenomena are evolutionary and which are not is an empirical question that can only be resolved through a case by case investigation of each phenomenon, but it is increasingly clear that a great deal of human culture is accessible to such an investigation.
BIBLIOGRAPHY
Boyd, Robert and Peter J. Richerson. The Origin and Evolution of Cultures. Oxford: Oxford University Press, 2005.
Boyd, Robert and Peter J. Richerson. Culture and the Evolutionary Process. Chicago: University of Chicago Press, 1985.
Cziko, Gary. Without Miracles: Universal Selection Theory and the Second Darwinian Revolution. Cambridge, MA: The MIT Press, 1995.
Dawkins, Richard. The Selfish Gene. Oxford: Oxford university Press, 1989.
Dawkins, Richard. “Universal Darwinism.” In Evolution from Molecules to Man by D.S. Bendall. Cambridge: Cambridge University Press, 1983, 403-25.
Dennett, Daniel C. Darwin's Dangerous Idea. New York: Touchstone, 1995.
Gewirth, Alan. “The Problem of Specificity in Evolutionary Ethics.” Biology and Philosophy I (1986): 297-305.
Maynard Smith, John and Eors Szathmary. The Major Transitions in Evolution. Oxford: W.H. Freeman and Company Limited, 1995.
Maynard Smith, John and Eors Szathmary. The Origins of Life: From the Birth of Life to the Origins of Language. Oxford: Oxford university Press, 1999.
Sterelny, Kim and Paul E. Griffiths. Sex and Death: An Introduction to Philosophy of Biology. Chicago: University of Chicago Press, 1999.
