With several articles recently appearing that were based on various aspects of evolutionary psychology, I thought it would be worth taking a closer look.

One of the ironies in examining evolutionary psychology is how many stories we can make up for ourselves without a shred of conclusive evidence, beyond simply sounding plausible.  This doesn't mean that they may not be true, but they certainly can't be considered scientific.  I thought it would be interesting to examine several points regarding evolutionary psychology before going further:

It is not an area of study, like vision, reasoning, or social behavior. It is a way of thinking about psychology that can be applied to any topic within it. (1)

While this sounds like a very reasonable assessment, it is almost immediately ignored by framing everything that follows as a specific point of study.  Five principles are then presented that frame the basis for evolutionary psychology.

Principle 1. The brain is a physical system. It functions as a computer. Its circuits are designed to generate behavior that is appropriate to your environmental circumstances.

The big problem here is in reducing the brain to a computer, which it isn't.  While it might be a useful analogy within a very narrow context, it is simply foolish to define biology in terms of recent human technological developments (i.e. computers, machines, etc.).  This is simply unacceptable, in the same way that electrons are not like billiard balls, neither is the brain a computer.  In truth, there is nothing in the operation of a computer that could find an accurate comparison to the brain's neurobiology (unless one is content to make the comparison simply because signals may be sent electrically).  However, by that logic, a television, telephone, and radio are all computers too.

Organisms that don't move, don't have brains.  Trees don't have brains, bushes don't have brains, flowers don't have brains.

This kind of misunderstanding is simply ridiculous.  One has to wonder what kind of brain bacteria possess.  Let's also not forget the mimosa plant (Mimosa piduca).

Principle 2. Our neural circuits were designed by natural selection to solve problems that our ancestors faced during our species' evolutionary history.

In this case, the problem occurs with words like "designed", because that already indicates a fundamental failure to understand evolution and natural selection.  In the first place, why presume that the brain evolved to "solve problems"?  There are organisms that don't even have nervous systems that are capable of that function.  More importantly, what problems are so unique to humans that they should be the only species to have "evolved" such a brain?  Considering the simple reality that there are no particularly unique problems that humans solve, then we must conclude that this is an insufficient reason to explain the existence of the human brain.  It is a classic error in assuming that modern day biological structures are necessarily adaptive.  After all, it is equally plausible to assume that brain development diverged due to a random mutation, and that it's subsequent benefits moved humans down a different evolutionary path.

For you, that pile of dung is "disgusting".

Once again, an interesting story, but simply not true.  Dung is often used to assess an animal that someone is tracking, and certainly carries vastly different interpretations depending on the animal of origin.  In fact, given the cultures which still use dung for fires and fertilizers, this assertion is clearly a product of a modern urban mindset rather than anything to do with human evolution or psychology.  This is so basic, that one can't help but marvel at how myopic this "understanding" of human psychology is.

But what did the actual designer of the human brain do, and why? Why do we find fruit sweet and dung disgusting?

This kind of statement is simply embarrassing.

Principle 3. Consciousness is just the tip of the iceberg; most of what goes on in your mind is hidden from you. As a result, your conscious experience can mislead you into thinking that our circuitry is simpler that it really is. Most problems that you experience as easy to solve are very difficult to solve -- they require very complicated neural circuitry

This certainly appears to be true, but I don't see why it's a principle of anything.  Once again, it seems much more appropriate to turn this around and argue that the "mind" exists in numerous organisms and it is only recently in human development that consciousness emerged as a trait.  I'm not clear why an individual's perception of their personal brain circuitry is of any consequence as a "principle".

...so complex, in fact, that no computer programmer has yet been able to create a robot that can see the way we do.

Doing what comes "naturally", effortlessly, or automatically is rarely simple from an engineering point of view.

It seems like the point is to warn against over-simplifying and yet that's precisely what occurs when words like "engineering" are used to describe a phenomenon which has never been successfully engineered.

Principle 4. Different neural circuits are specialized for solving different adaptive problems.

Interesting idea, but where's the evidence for this?  This requires a level of study that simply doesn't exist.  In the first place, we have to demonstrate that there are specific psychological responses that are unique to particular adaptive problems.  We then have to demonstrate that these behaviors are heritable and governed by neural circuits that fulfill no other more general purpose.  This is exceedingly unlikely and the most likely explanation is that our brain is much more flexible than it is specialized to specific problems.

This isn't to say that there aren't specific capabilities that our brain has evolved for, but it is unlikely that they are unique to humans and instead will likely prevail throughout many other mammal's brains.  So while we can certainly agree that there are visual or auditory centers in the brain, it is not at all clear that they are uniquely human, nor does it explain anything about how the brain actually maps such sensory data into the context of a "mind" or consciousness.

For example, we all have neural circuitry designed to choose nutritious food on the basis of taste and smell -- circuitry that governs our food choice. But imagine a woman who used this same neural circuitry to choose a mate.

It is also difficult to determine whether these principles are being written as serious definitions or whether they are intended to entertain school children.  To suggest that our brain is operating substantively different in choosing food versus choosing mates, indicates such a fundamental misunderstanding about neurobiology, it is mystifying.

Principle 5. Our modern skulls house a stone age mind.

This makes little sense, since it arbitrarily separates "mind" from "brain".  After all, this assertion basically argues that evolution has stopped or is unresponsive to human needs.  This claim flies in the face of the actual evidence which indicates that humans are a phenomenally adept species and are extremely well adapted to their environment.  In fact, the fallacy appears to be based on the notion that somehow we shouldn't experience any challenges, but that rather we should have evolved so that anything we engage in is "effortless".  However, it should be obvious that we cannot behave or perform in ways that our brain can't handle.  So, while we may personally believe that it isn't as easy as we might wish, there is no evidence to suggest that we aren't adapted to everything we do.

This becomes especially relevant when we want to argue about how our culture has changed us and somehow our behaviors have difficulty keeping pace with those changes.  Where is the evidence for this?  Is this being assumed simply because of the perception of increased psychological disorders or stresses?  Once again, what evidence do we have that such disorders haven't always been present?

Generation after generation, for 10 million years, natural selection slowly sculpted the human brain, favoring circuitry that was good at solving the day-to-day problems of our hunter-gatherer ancestors -- problems like finding mates, hunting animals, gathering plant foods, negotiating with friends, defending ourselves against aggression, raising children, choosing a good habitat, and so on. Those whose circuits were better designed for solving these problems left more children, and we are descended from them.

This statement is simply stupid, because it presumes that we are the hapless victims of a natural selection process that simply can't keep up.  It demonstrates a uniform failure to understand that natural selection does not "sculpt" nor "design", but simply ensures that an organism has the necessary traits to survive in the environment in which it exists.  No matter how it is considered, the filter of natural selection doesn't only work sometimes.  If a species survives (including humans) then it has passed the "selection test".  If the point is to argue that our brain is maladaptive, then it requires a bit more than fantasy stories about how cavemen are believed to have lived.  It is also curious that of all the attributes listed, virtually none of them are demonstrably "hard-wired".  With this kind of basic misunderstanding, it's difficult to assign much credibility to Evolutionary Psychology claims.

After examining these principles and many other points regarding various debating points such as "nature vs nurture" it becomes clear that evolutionary psychology simply isn't ready for prime time, either as a discipline or even as a perspective.  In fact, a strong argument can be made that when using evolutionary biology as a perspective in examining behavior there is a real risk of telling oneself convenient stories based on little more than conjecture or imaging what "things must've been like".  

Without some insight that is nothing short of miraculous, there is no such thing as evolutionary psychology.  So for those that want to insist otherwise, here's the criteria that must be met:

1.  Demonstrate that the behavior is neurologically specific enough to be predicted.
2.  Demonstrate that such behavior is heritable (Note:  Learning, by itself, is not sufficient).
3.  Demonstrate that such heritability actually is adaptive.

These requirements are quite difficult to meet for many aspects of biology, especially that of establishing that a trait is adaptive.  However, to glibly toss off explanations based on some arbitrary notion about how early humans lived is simply idle speculation and nonsense.
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(1) All quotes and references come from the Center of Evolutionary Psychology, "The Evolutionary Psychology Primer" 
http://www.psych.ucsb.edu/research/cep/primer.html