By explaining what they have done well, and what they have gotten wrong, in regards to introducing the subject hopefully this article will serve the dual purpose of providing a good explanation of basic concepts in the field, as well as providing an example of the sort of back and forth advocates of EP have with their detractors.
The article this was taken from was online at Rational Wiki circa January 2015. Some editing has been done for clarity and to remove links and citations that were deemed largely irrelevent. Please visit the page linked to above in order to appreciate the source in context.
Evolutionary psychology (EP) is an attempt to explain complex human behaviour in terms of the evolution of the human brain and its manifest psychological mechanisms. This includes fitness advantages that such behaviour gives, i.e., by natural selection. In the broadest sense, behaviours or social constructs are seen as adaptations in the same way as physical adaptations. However, evolutionary psychology also investigates behaviours as a by-product of natural selection (or "spandrels," to use Stephen Jay Gould and Richard Lewontin's term) or simple evolutionary noise.
Kudos to the author(s) for admitting here that evolutionary psychology admits to other evolutionary drivers besides natural selection in terms of what the origin of certain behaviours could be.
However, there are also things here that demonstrate the biases of the author(s).
Are the phenomena examined by evolutionary psychologists any more “complex” than those examined by other perspectives in psychology? Not necessarily, and that the impression intended by suggesting they are may be an attempt to make evolutionary psychology appear more audacious in its claims than other branches of psychology or social science.
It is misleading to claim that social constructs are seen as adaptations by evolutionary psychologists. Where there is controversy over whether or not something is a social construct evolutionary psychologists may have their own ideas about the degree to which innate factors influence the behaviour. Where social constructs have predictable effects on behaviour evolutionary psychology may also help explain why such effects are predictable. However evolutionary psychologists are generally happy to give other psychological perspectives their due when evidence for alternative or complementary explanations are available.
Proponents of evolutionary psychology argue that the long term evolutionary effects of such behaviours go a long way to explaining why some behaviours are universally seen among all humans or some groups of animals, while critics often regard much evolutionary psychology as pseudoscientific, in the sense of generating explanations that cannot be disproven and having extremely low standards of evidence when compared to studies of non-human animal behaviour (for instance, not requiring that any given behavioural trait be established to have a genetic component before evolutionary explanations are sought for it).There are plenty of studies of animal behaviour which include hypotheses about evolutionary justifications for such behaviour without mentioning which genes are responsible.
For example – the attraction peahens have for the tail feathers of peacocks is a classic illustration of sexual selection, and it was proposed before Mendel’s discoveries regarding genes were even published.
What might be fairer to say is that some types of animal behaviour studies are more stringent than much evolutionary psychology, because comparisons between genetics and behaviour can be confidently drawn.
But then it would also follow that it would be fairer to say that some evolutionary psychology is more stringent than some animal behaviour studies for the same reason (for example those that complement studies into conditions or pathologies that are linked to genetics).
In short – this paragraph seems to be comparing the most stringently understood studies into animal behaviour to EP as a gestalt, and suggesting that that’s the whole of the picture.
Assumptions of evolutionary psychology
Evolutionary psychology has one basic premise: that human behaviour and cognition (collectively known as psychology are governed to a great extent by Darwinian evolution. In other words, evolutionary psychology proposes that genetics is an important mechanism behind shaping psychology. When evo psychs formulate hypotheses they try to use the Darwinian evolutionary history of humans, even though there is little evidence to corroborate their specific account.The evidence backing up hypotheses will vary from hypothesis to hypothesis. Moreover it is often the generation of hypotheses that lead to the methodologies from which more evidence is gathered.
As an apparent objection this seems like the old creationist call of “but there are gaps in the fossil record”. That the evidence is patchy is not itself evidence that the field is making undue pronouncements.
Evolutionary psychology attempts to provide explanations for certain human behaviours. However, whether or not these generated explanations can then be established as plausible or consistent is a separate question. Areas in which an evolutionary approach to psychology is often applied include sex, morality, religion, and in-group/out-group effects.
The author(s) have chosen to provide a list of controversial subjects here. An evolutionary approach to psychology is also applied to things like aesthetics, memory, perception, diet, theory of mind, play, emotions, parenting and (to judge by Psychology Today articles) how and why humans and canines get along so well.
This leaves the impression that evolutionary psychology merely deals with divisive and controversial subject matter. Whilst there is no doubt that sexuality, morality, religion and group dynamics are subjects of interest to evolutionary psychology, they aren't the focus of the field in the way the author(s) suggest.
While no scientist worth their salt will dispute that humans are the product of evolution, they will posit that they are a product of culture as well. A very clear picture has emerged in the literature and it goes against evolutionary psychology's main assumption — recall that they claim human psychology is governed to a great extent by Darwinian evolution. So, it is not that human psychology is not in part governed by our evolutionary history, but that social and cultural (i.e., on the levels of analysis above genetics) factors override the genetic layer in the overwhelming number of cases. What this means is that many of the explanations and hypotheses evo psychs propose are fundamentally misplaced, leading to begging the question.“A great extent” and “in part” are not mutually exclusive states of affairs, so unless a sociocultural explanation can be definitively shown to be the sole phenomena behind a behaviour there is no begging of any question based on this assumption.
What could be begging the question would be to privilege any one psychological perspective over another when it comes to asking what influences a given behaviour. This isn’t something people working in psychology tend to do, even if they personally focus on a particular perspective for their own research.
Nor do the various perspectives trump one another, the answer to any particular question about human behaviour may include reference to several perspectives.
For example: why would a given individual wear a coat on a cold day?
On a personal level – maybe they don’t like being cold, and experience has taught them that wearing a coat mitigates against the cold.
On a social or cultural level – they may have peers or elders who advise them to wear a coat, it may be the custom to wear such clothing in certain seasons, they may have heard local idioms like “don’t cast a clout ‘til May be out”.
On an evolutionary level – humans generally experience low temperatures as unpleasant and seek warmth, and this behaviour helps them to survive and conserve energy.
None of these answers are wrong. None of them trump the others. Understood properly they even complement one another.
There seems to be this suggestion that evolutionary psychologists ignore culture. They don’t, but the focus of their work is either or cross cultural commonalities, or on variations between cultures that may yet illustrate a cross cultural commonality (such as predictable effects of cultural change). Presumably if you feel it somehow wrong for evolutionary psychologists to focus on evolutionary explanations then you also think it wrong for social psychologists to study how behaviours are influenced by culture. If not, why not?
In general, the idea of applying natural selection to human behaviour is controversial. The reason is that in order for natural selection to occur, a trait must both be genetically inherited and exposed to sufficient selective pressure.That it is controversial is without doubt – but is such controversy justified? The author(s) of the Wiki did say earlier that natural selection wasn’t the only evolutionary driver discussed by evolutionary psychology, and the reasons for discussing natural selection need to be examined on a case by case basis. So what changed?
In studies of animal behaviour, the first requirement can usually be assumed in animals that lack cultural transmission. In humans, it is often not possible to establish whether or not given behavioural traits have a genetic component, as controlled experiments are not available for ethical and historical reasons, and workarounds such as twin studies often suffer from fatal flaws. A further problem exists in that the definition of a discrete 'trait' is difficult to achieve; a behavioural trait exists in a behavioural context, and cannot be separated out the way that 'eye colour' can.
The author(s) are forcing a conclusion to say that such things “cannot” be done. For example would the author(s) agree that all the following behavioural traits are equally difficult to isolate and distinguish?
1) Ability to perceive differences between shades of red and green.
2) Improved processing in recognition of faces compared to that of objects.
3) Theory of mind - the ability to work out what someone else likely knows or does not know.
4) A shortcut to logical problem solving in situations where you might feel another person is trying to fool you.
All these proposed traits have been studied under control conditions, twin studies have not played an undue role in such a process, and they have strong cross-cultural support. This isn’t to say they are all equally solid in terms of how they are understood (colour-blindness is a much more studied phenomena than a cheater-detection module, for example) but they are all understood to a degree vastly beyond that illustrated in the wiki entry.
In regards to the presence or absence of selective pressure, critics allege that much of evolutionary psychology's claims about selective regimes are pseudoscientific in nature, as proposals about particular selective pathways often cannot be theoretically disproven.
As before, it’s true to suggest such critics exist – but are they credible? If not, is it really in the interest of a wiki devoted to rationality to mention them?
For example – the hypotheses in the experiments which led to the understanding of the phenomena discussed earlier were all individually falsifiable.
There is a difference between something which isn’t falsifiable and something which hasn’t been falsified. In retrospect some things that haven’t been falsified can look to be constructed in post-hoc fashion unless you know about how the body of evidence for such things was assembled. Even if they were constructed post-hoc (and they weren't) they could still be falsified, by coming up with further hypotheses for fair and logical tests of the proposed phenomena. If such hypotheses worked and were clearly demonstrated they would lead to a body of counter-argument that would undermine the proposed phenomena.
However such an effort would have to amount to more than pointing out some picayune sociocultural variation affecting the behaviour in question.
In a broader sense, they allege that EP has failed to produce any new insights into human evolution that move beyond a purely speculative character, remaining at the level of generating hypotheses without having generated evidence to build upon these initial hypotheses. As such, it hasn't matured into a field of study analogous to other areas of biology, remaining merely a novel proposal.
This line of argument suffers from a case of comparing apples and oranges. Evolutionary psychology isn’t in competition with biology, it’s applying insights and discoveries of biology to the questions of psychology.
Others argue that in some cases it works, in others it doesn't and it is important to keep this in mind. This is not to say that behaviours can't confer an advantage in the natural selection process, it's just that the law of "I'm sorry, it's a little more complicated than that" applies very well to evolutionary psychology. Most importantly, the evolution of (for example) aggression, would select for all genes correlated with aggression - including those that have far reaching effects on the other traits - but not for aggression itself.
The author(s) seem to be suggesting a hypothetical evolutionary psychologist who has provided a simple story for the development of aggression. Such a strawman caricature likely never existed. What may exist is discussion as to what sort of evolutionary problems aggression solves, the circumstances under which it is a benefit or a liability. Given the fact that such discussions are never framed along the lines of “and that’s all there is to aggression” the patronising advice as applying the law of "I'm sorry, it's a little more complicated than that" isn’t required. That putative law can be taken as implicit in any discussion of psychology.
As to the last point, it seems like semantic quibbling. Given that many different genes might feasibly contribute to aggression, might aggression develop without the selection of all of the genes correlated with aggression? Yes. The innate causes of Mantis Shrimp and Osprey aggression are not likely to be genetically identical.
Specific debates about evolutionary psychology
Straw men and heated arguments
Proponents and critics alike are prone to making straw man arguments in both popular literature and sometimes scholarly literature. Firstly, critics of EP are prone to dismissing it as genetic determinism, although such claims are rarely, if ever, made by proponents. On the other side, self-righteous promoters of EP (and especially its pop incarnations) will strawman critics as denying biology, "social constructionists," "politically correct," or even "radical feminists." However, prominent EP critics such as David J. Buller do not repudiate that the human brain is the product of evolution; he divides EP into what he sees as upper-case "Evolutionary Psychology" (i.e., EP of the Flintstones variety) and lower-case "evolutionary psychology" based on better research and a broader view of evolutionary theory. Similarly, Stephen Jay Gould argued that evolutionary psychology was only problematic insofar as it was concerned with finding selective, adaptationist explanations to the exclusion of others; he viewed human cognition as a spandrel that, once evolved, became subject to cultural and social factors.
He would have been insane to say that something as complex and useful as human cognition could be regarded, in its totality, as a spandrel.
Here’s something he did say:
“I welcome the acknowledgement of self-professed “evolutionary psychologists” (compared with the greater stress placed by the “sociobiology” of the 1970s on a search for current adaptive value) that many universal traits of human behaviour and cognition need not be viewed as current adaptations, but may rather be judged as misfits, or even maladaptations, to the current complexities of human culture.” – S. J. Gould, The Structure of Evolutionary Theory.
So rather than calling human cognition a spandrel he here seems to be suggesting that universal traits of human behaviour and cognition might well not be adaptive to the modern world, having been adaptive to the world of the past and now having inconsequential, or even counterproductive, influence. This is something which is no news to evolutionary psychologists, as he himself mentions.
This has led some to differentiate between two "senses" of evolutionary psychology in the sense that Buller has. "Capital EP" has also been referred to as "narrow-sense EP" or the "Santa Barbara school" due to its association with certain key assumptions and specific researchers. Many criticisms of evolutionary psychology are directed at this narrow-sense of EP.
Common criticisms of evolutionary psychology
1. genetic determinism. In some cases this is genuinely a straw man, as EP does attempt to describe the interaction between genes and environment in certain cases. EP generally claims that environmental input is necessary for genetic programs to operate. However, in situations where there is an unambiguous interaction between genes and environment (for example, human height is determined both by genetics and nutrition), both the genetic and environmental component of the given trait can be independently established to some degree. Critics allege that EP often imposes no requirement that a given behavioural trait be established as having a genetic component or overestimates the influence of that component. In many cases, EP assumes the genetic component to exist, and assumes that it has a substantive impact on human behaviour, when neither clause has actually been shown to be true.
The critics are right enough in this particular allegation – but they miss a wider point.
To repeat an earlier point – there are other perspectives of psychology investigating other reasons for human behaviour. If evolutionary psychology devoted it’s time investigating reasons other than evolutionary reasons for human behaviour it wouldn’t be evolutionary psychology any more.
Just like social psychologists concentrate on cultural reasons for differences in human behaviour without requiring settlement on which innate factors might be involved before doing so.
2. EP relies on guesswork about a hypothesised "Environment of Evolutionary Adaptedness" (EEA) because little is known about the environment of the late Pleistocene. The EEA does not refer generally to one single evolutionary environment, but specifically the environment in which a specific adaptation developed. Critics charge that this enables proponents of EP to shift the ground in debates and create a situation in which no EP claim can ever be disproven, as a new EEA can be established any time an old one is shown to be unlikely, a hallmark of pseudoscientific thinking.
Is there an example the author(s) can provide of such a shift in debate occurring? If so would such a shift be any more egregious than those shifts in other fields of science when new evidence is uncovered?
The EEA is simply the only honest way to think about the development of a phenotype over evolutionary time. There won’t have been any complex phenotype that appeared out of nowhere for a certain function in a given place. If such a notion is pseudoscientific just because it is nebulous then once again Creationists are right to complain about gaps in the fossil record. It’s obviously frustrating that the EEA can’t be fully detailed, but nevertheless it’s exactly what reason and evidence point to. What would make the charge of psuedoscience credible would be if there was a better explanation that suited the available evidence. There isn't one.
3. EP is selection-centred and adaptationist. While some EP crosses into Lamarckian "hyper-adaptationist" territory and Panglossian thinking, much research in EP explains certain psychological phenomena as by-products (or "spandrels"). Stephen Jay Gould regarded evolutionary psychology as a potentially legitimate field of research, and lamented that it was held in thrall by adaptationist, selection-centred approaches to problems, while actual human behaviour may not have been shaped by selective evolutionary processes. EP can and does cross into the territory of hyper-adaptationist, speculative, unfalsifiable "just-so stories." A number of concepts, findings, and methodologies in the field have been criticized for being implausible or false by the standards of neuroscience, evolutionary biology, and anthropology. Application of pop EP ideas, both by pop-science writers such as Steven Pinker and by fields outside of traditional EP have, again, been snarkily referred to as "Flintstones thinking."
At time of writing the wiki provides no citations of evolutionary psychology that can be fairly regarded as Panglossian or Lamarckian hyper-adaptationist. can we get some?
As mentioned above, Gould’s actual position on evolutionary psychology, at least by the end of his life, was somewhat more nuanced than the author(s) suggest.
4. EP ignores proximate explanations of psychological phenomena. EP attempts to explain proximate explanations provided by cognitive, social, etc. psychology with an ultimate evolutionary explanation. These explanations are not mutually exclusive, but complementary. However, the issue is whether or not the "ultimate evolutionary explanation" is ever necessary to explain observed phenomena to begin with. EP proposals often fail to pass the test of Occam's Razor, failing to establish that EP provides an explanation for data that can't be explained with more mundane approaches.
As explained earlier – there should be no privileging of a particular psychological perspective when it comes to an explanation of human behaviour. When it comes to social psychology evolutionary psychology can often help illustrate the framework within which predictable changes to human behaviour as a result of cultural shifts occur. To suggest the evolutionary psychology ignores cognitive psychology when it comes to these issues is particularly nonsensical, given that evolutionary psychology typically follows cognitive psychology’s lead when it comes to examining psychological mechanisms. In regard to cognitive psychology it's rather difficult to imagine where a "proximate explanation of psychological phenomena" might be provided that would render an evolutionary explanation moot. Any examples?
5. EP is unfalsifiable, In some cases, EP generates explanations for behaviour that cannot be falsified, opening it up to charges of classical pseudoscience. One example is the changing EP explanations for traits such as altruism, in which multiple EP explanations have been put forward to explain the trait. Ground can be shifted between group selection, reciprocal altruism, and kin selection; if one explanation is shown to be inappropriate, the other can be invoked.
There is a difference between the existence of competing and complicated explanations, or even controversies within a field, and something being unfalsifiable.
Is there any coherent argument as to why, when discussing something as complicated as altruism, there should be a problem with ceding that reciprocity and social and/or genetic kinship should not all play a part? No? Then any discussion of altruism will cover such topics, and shifts in emphasis depending on what sort of questions are raised and what sort of evidence is under scrutiny can be expected.
6. EP relies on the assumption of massive modularity. EP posits domain-specific modules that are shaped by natural selection to perform a specific task as well as claiming that the brain is composed largely of these modules (hence "massive modularity"). Critics contend that neuroscientific data does not support massive modularity.
Such critics just don’t know what they’re talking about. The brain is not “composed” of modules in a physical sense because modules aren’t things the brain is, but things the brain does. You can’t see “perceiving the colour green” in the brain as a physical thing, but nevertheless it is something the (typical human) brain does. You might be able to see what parts of the brain are more active when a given individual perceives the colour green, and this might lend some support to the notion that certain brain architecture is associated with a certain mental module, but they aren’t the same thing.
Many different mental modules may make use of the same parts of the physical brain.
The media discovers evo psych
The mainstream media and pop science love evolutionary psychology. In the specific cases or studies brought to the public's attention in newspaper articles, situations are often over-simplified to the point of being plain silly. Even qualified scientists who should know better can sometimes not resist the temptation to attribute every behavior that is (stereotypically) associated with a particular gender in contemporary society is actually the result of something our remote ancestors did to survive on the savannah. In fact evolutionary psychology, at least in its "popular" incarnation, can be an example of using "science" to imbue just-so stories with an air of credibility that actually justifies sexism and discriminatory behavior.
An example is a supposed "study" which explains why boys prefer blue and girls prefer pink.
Poor Anya Hurlbert and Yazhau Ling, will a day come when they aren’t held up as undeserving pariahs by those who want to criticise evolutionary psychology? Very brief defence of them: they are neuroscientists who have authored a huge number of papers and colour perception is a particular area of expertise. This study (not a ‘supposed “study”’ by the way – it’s just a plain old study) looks into colour preferences with two sets of independent variables: woman or male, and British Han Chinese or British Other. Neither of the researchers identify as evolutionary psychologists and the paper hasn’t exactly set the evolutionary psychology world alight. It does show some sex and cultural differences in colour preference. They conclude a socio-cultural influence (demonstrable because British Han Chinese tended to state a preference for red more than Other British participants) and speculate that there might be an evolutionary reason for why the sex difference observed holds cross culturally (note that by speculating they would allow for alternative explanations, such as an enhanced socio-cultural effect, even if they hadn't openly acknowledged such a thing ... which they did anyway).
In the view of pop-evolutionary psychology, this is because women being gatherers and men being hunters, liking pink was most likely to allow you to find berries so women grew to be attracted to pink. So far, so common sense, however, the idea completely ignores many established facts (and blueberries).
Red-Green colour sensitivity is always going to be more useful in foraging than Blue-Yellow colour sensitivity because the leaves rather than the fruit are primary indicators of the species of plant (and also form a lot of the edible matter). So even if blueberries did predominate as a food crop in the EEA (unlikely) RG sensitivity may well be useful in locating them.
It’s not that women don’t mentally appreciate blue less than men, it is that 10% of men (about 1 in 10 are RG colour-blind) are worse than almost all women at distinguishing shades of red and green. Does this mean such a thing is an adaptation? In all likelihood no (hence why the authors of the study just speculate), but phenomena beyond the purely socio-cultural are at play here.
Such that colour preferences change from place to place, and even that in the Western world (where the concept of gender-specific colours is strongest) 100 years ago it was reversed; i.e., the soft colour of blue was associated with the Virgin Mary, and was thus feminine, while men preferred associations with strong, passionate colours such as red and pink.
The author(s) of the Wiki are confusing two different phenomena:
1) What colours people express a preference for under control conditions.
2) What colours were associated with particular genders at different times.
It might be perfectly logical for men to have preferred looking at blue, and for women to wear blue. Socio-cultural changes in fashion could well indicate changes in preference, but seeing as what colours you like to look at does not necessarily influence what colours you wear (or buy for your children to wear) this sort of reasoning isn’t an argument against notions of evolved colour preference. What would demonstrate it? More experiments of the kind organised by Hurlbert/Ling with different populations that demonstrate a break in the pattern. If the pattern continues to hold cross culturally then the notion will have more support. If the pattern varies wildly between cultures it will be undermined. A good experiment to test the specuilation might be to see if women can, cross-culturally, learn plant identification better than men under control conditions. If not then we can probably forget this whole thing - but bringing up the fact that fashions have changed over the years does nothing to challenge the ideas expressed in the study.
Another colour that's now seen as feminine, purple, was once associated with the Roman Empire, and with it, was seen as masculine back in the day. Indeed, a purple cloak was part of the Roman Emperor's regalia. To "wear the purple" was a euphemism for assuming this position, and the word itself became used for royalty in general.
The reason purple clothing was considered suitable for royalty by the ancients surely has more to do with it being dangerous and expensive to produce, rather than inherently gendered one way or the other? (The only way to produce a lasting purple dye at the time was a notoriously noxious process involving caustic fluid and rotten shellfish – it was therefore a luxury to own purple cloth).
That purple was associated with effete bluebloods may explain why it gained a “feminine” association. That women may perceive the red hues in purple more vividly than men in gestalt may exacerbate the association. This is another example of why sociocultural explanations may be better understood through appreciation of an innate psychological difference.
The curious case of Kevin MacDonald
Another example of how evolutionary psychology can go in a wrong direction is the work of Kevin B. MacDonald, who uses evolutionary psychology to explain stereotypical Jewish characteristics as being part of a group evolutionary strategy. His trilogy of books on the subject, especially The Culture of Critique (1998), has been called anti-Semitic for its assertion that Jews gravitate toward politics to promote policies in opposition to the dominant culture. In 1995 he was elected to a six year term on the executive council of the Human Behavior and Evolution Society, but by 2007 he had increasingly associated on a working level with anti-Semitic and white nationalist groups, causing the California State University at Long Beach, where he is a professor, to publicly distance itself from his views. In 2010 he became the director of the newly-founded American Third Position political party. His "theory" essentially asserts Jewish biological superiority, but turns this around and uses it to argue that anti-Semitism is justified as "self-defense."
It does seem odd that this apparently rebarbative individual is the only person associated with evolutionary psychology who receives an entry of his own in the Wiki, and I take it as another sign of the biases of the author(s). I do note the Rational Wiki pages on medicine aren't filled with guff about Josef Mengele (at time of writing).
Other evolutionary approaches
Despite the fact that the field explicitly calling itself evolutionary psychology is relatively new, the idea goes back to Charles Darwin. Darwin's works The Descent of Man and The Expression of the Emotions in Man and Animals included applications of evolutionary thought to psychology. Other evolutionary approaches to human psychology and behavior have variously gone under the names of "sociobiology," "human behavioral ecology," "gene-culture co-evolution," and "human behavior and evolution." Some critics have contended that evolutionary psychology is a rebranding of sociobiology. While a number of former sociobiologists have moved into the field of evolutionary psychology, the focus on psychological mechanisms is what distinguishes the two approaches. As Leda Cosmides and John Tooby write: "...in the rush to apply evolutionary insights to a science of human behavior, many researchers have made a conceptual 'wrong turn,' leaving a gap in the evolutionary approach that has limited its effectiveness. This wrong turn has consisted of attempting to apply evolutionary theory directly to the level of manifest behavior, rather than using it as a heuristic guide for the discovery of innate psychological mechanisms."