A popular approach to explaining consciousness and other attributes of the human mind and soul is to attribute all of it to evolutionary mechanisms. The purpose of the new field of evolutionary psychology (EP, or Evo Pyscho, my own invention) is to find “scientific” explanations for human characteristics within the context of evolutionary adaptation. The field is based on the premise that all human behaviors and characteristics are the result of evolutionary adaptations to survival conditions during the evolution of humanity. Sociobiology is a related area of study that also incorporates this premise and strives to find evidence for it.

There is of course, plenty of evidence to be found. Sexual jealousy, hunger for sweets, even altruism toward kin can all be “explained” as adaptations to primitive conditions. The problem with this approach is that it isn’t always scientific, since the evidence used is sometimes a “just so” story that sounds logical and meaningful. In these cases the premise is a more of a faith statement with no basis of proof. And it may not be falsifiable. There is no possible human trait, real or imagined, that cannot be postulated to result from some evolutionary selective advantage.

Take, for example the well-known human tendency to bite one’s fingernails when nervous. We could say that long finger nails present an impediment to manual dexterity, which is needed to properly wield a weapon, and therefore when nervous the human tends to be sure that his/her fingernails are as short as possible. This is complete nonsense which I just made up without more than a moment’s thought. But it sounds like it makes sense..

Or take a fictional trait, like the urge to urinate when undergoing high-speed movement. That arose because humans never moved at high speeds unless they were being dragged away by a large carnivore, and urination was a useful way to signal distress to any other human passing by and also disgusted the animal enough to let go. Before you laugh, read some actual examples and explanations given for real human behavior by the “science” of evolutionary psychology.

Here are few quotes:

Physically more attractive parents are more likely to have daughters than physically less attractive parents…

It is therefore reasonable to infer that our ancestors must also have limited their daily activities to daylight, and sustained nocturnal activities are largely evolutionarily novel.  The hypothesis would therefore predict that more intelligent individuals are more likely to be nocturnal than less intelligent individuals.

Black women have lower average level of physical attractiveness net of BMI. Nor can the race difference in intelligence (and the positive association between intelligence and physical attractiveness) account for the race difference in physical attractiveness among women.

Satoshi Kanazawa

To be sure, the entire field of evolutionary psychology should not be judged by the writings of one controversial individual. Some EP ideas are more logical, some have some degree of reliable data, and some are undoubtedly correct. But often there is no actual evidence for any of the claims made, other than that they sound logical.

Modern humans have been around between 50 and 100,000 years (according to the cultural evidence of anthropology) and emerged as a biological species about 100,000-200,000 years before that. These are extremely short time spans for any kind of Darwinian evolution, and the idea that somehow there was enough time for humans to evolve all the traits we see in thought processes, sexual activities, child rearing, thinking, language, art and so on, is not compelling. If, however, these traits evolved in earlier hominin species, we need to be sure that the environment and behavioral selection pressures for those earlier ancestors were equivalent to those of early H. Sapiens. This may or may not be true, depending on the particular situation.

Lets take a closer look at a couple of mainstream EP claims brought to my attention by Ben Goldacre writing in his blog Bad Science. “Women walk more sexily when they are at their least fertile,”  according to a study in the journal Archives of Sexual Behavior. The finding might be true, based on survey research, but the explanation for something that seems counter intuitive is one of those things that only an EP mind set could produce. In reporting on this “Science” the Daily Mail reports “The apparently contradictory finding – which belies earlier evidence that women’s behaviour becomes more alluring around the time of ovulation – amounts to an evolutionary con-trick on men, scientists said yesterday. Genuine signals of sexual availability, such as subtle changes in smell and facial expressions, can be detected only close up. If she flaunts herself too openly at fertile times, she could be made pregnant by an unsuitable man,”

Well, that makes sense, right? And if it isn’t true, we can always think of something else.

In another EP study, published in the respected journal Current Biology, scientists found that girls prefer pink or reddish hues, compared to boys who prefer blue. Again this was the result of a survey. But the conclusion, based on nothing, was this was probably due to female humans gathering berries, while the men hunted. Sounds logical until we find out that the female preference for pink is a modern Western cultural concept, and that a bit less than 100 years ago pink was considered a masculine color compared to the softer, more feminine blue. Oh well.

Lurking behind evolutionary psychology is a theological statement which is as follows: “There is no God, and therefore ALL human characteristics must be explainable by scientific (evolutionary)  principles”.  The converse of that statement is “Humans are NOT totally explained by evolutionary principles” which leads to the question of what other explanations for human behavior and human nature could there be? There are many answers to this question, some of them theological, others not.

The purpose of my argument here is not to suggest that the failure of Evo Psycho leads to a conclusion that humans were created by God (although I do believe that humans were created by God). What I am trying to suggest is that it is a bad mistake to allow a religious view (there is no such thing as a god) to lead to the acceptance of pseudoscience. It isn’t Christian theology, but the reputation of science that suffers from this error.