Evolved psychological mechanism

Definition:

An evolved psychological mechanism is a set of processes inside an organism with the following properties:

An evolved psychological mechanism exists in the form that it does because it solved a specific problem of survival or reproduction recurrently over evolutionary history.

An evolved psychological mechanism is designed to take in only a narrow slice of information. Consider the human eye. Although it seems as though we open our eyes and see nearly everything, the eye is actually sensitive only to a narrow range of input from the broad spectrum of electomagnetic waves. … Similarly, the psychological mechanism of a predisposition to learn to fear snakes in designed to take in only a narrow slice of information - slithery movements from self-propelled elongated object. Our evolved preferences for food, landscapes, and amtes are all adesigned to take in only a limited subset of information from among the infinite array that could potentially constitute input. The limited cues that activate each mechanism are those that recurred during the EEA or those in the modern environment that closely mimic these ancestral cues.

The input of an evolved psychological mechanism tells an organism the particular adaptive problem it is facing. The input of seeing a slithering snake tells you that you are confronting a particular survival problem, namely, physical damage and perhaps death if bitten. … This almost invariably occurs out of consciousness. Humans do not smell a pizza baking and think, “Aha! I am facing an adaptive problem of food selection!” Instead, the smell unconsciously triggers food selection mechanisms, and no consciousness or awareness of the adaptive problem is necessary.

The input of an evolved psychological mechanism is transformed through decision rules into output. Upon seeing a snake, you can decide to attack it, run away from it, or freeze. … The decision rules are a set of procedures - “if, then” statements - for channeling an organism down one path or another. (ANN 등을 고려하지 않은, 계산에 대한 너무 경직된 견해가 아닌지. —AK, 2005-11-11)

The output of an evolved psychological mechanism can be physiological activity, information to other psychological mechanisms, or manifest behavior. Upon seeing a snake, you may get physiologically aroused or frightened (physiological output) you may use this information to evaluate your behavioral options such as freezing or fleeing (information to other psychological mechanisms); and the consequence of this evaluation is an action, such as running away (behavioral output).

The output of an evolved psychological mechanism is directed toward the soluition to a specific adaptive problem. … The main point is not that the output of a psychological mechanism always leads to a successful solution, but rather that the output of the mechanism on average tended to solve the adaptive problem better than competing strategies in the environment in which it evolved.

An important point to keep in mind is that a mechanism that led to a successful solution in the evolutionary past may or may not lead to a successful solution now. … The central point is that evolved mechanisms exist in the forms that they do because they led to success on average during the period in which they evolved. Whether they are currently adaptive - that is, whether they currently lead to increased survival and reproduction - is an empirical matter that must be determined on a case-by-case basis. —p50-52, Evolutionary psychology

Important properties:

This section examines several important properties of evolved psychological mechanisms. They provide nonarbitrary criteria for “carving the mind at its natural joints” and tend to be problem specific, numerous, and complex. These features combine to yuld the tremendous flexibility of behaivor that characterize modern humans.

Evolved psychological mechanisms provide nonarbitrary criteria for “carving the mind at its joints.” A central premise of evolutionary psychology is that the primary nonarbitrary way to identify, describe, and understand psychological mechanisms is to articulate their functions - the specific adaptive problems they were designed by selection to solve.

Consider the human body. In principle the mechanisms of the body could be described in an infinite number of ways. Why do anotomists identify as separate mechanisms the liver, the hear, the hand, the nose, and the eyes? What makes these divisions nonarbitrary compared with alternaive ways of dividing the human body? The answer is function. … Evolutionary psychologists believe that similar principles should be used for understanding the mechanisms of the mind. Although the mind could be divided in an infinite number of ways, most of them would be arbitrary. A powerful nonarbitrary analysis of the human mind is one that rests on function. If two components of the mind perform different functions, they can be regarded as separate mechanisms (although they may interact with each other in interesting ways).

Evolved psychological mechanisms tend to be problem specific. … Adaptive problems, like street addresses, are specific - don’t get bitten by that snake, select a habitat with running water and places to hide, avoid eating food that is poisonous, select a mate who is fertile, and so on. There is no such thing as a general adaptive problem. All problems are content specific.

Because adaptive problems are specific, their solutions tend to be specific as well. … General solutions fail to get you to the right adaptive solution. …

In summary, problem specificity of adaptive mechanisms tends to be favored over generality because (1) general solutions fail to guide the organism to the correct adaptive solutions; (2) even if they do work, general solutions lead to too many errors and thus are costly to the organism; and (3) what constitutes a “successful solution” differs from problem to problem (the criteria for successful food selection differ from the criteria for successful mate selection). The adpative solutions, in short, have dedicated procedures and content-sensitive elements to solve adaptive problems successfully.

Humans possess many evolved psychological mechanisms. … Because specific problems require specific solutions, numerous specific problems will require numerous specific solutions. Just as our bodies contain thousands of specific mechanisms - a heart to pump blood, lungs for oxygen uptake, a liver to filter out toxins - the mind, according to this analysis, must also contain hundreds or thousands of specific mechanisms. Because a large number of different adaptive problems cannot be solved with just a few mechanisms, the human mind must be made up of a large number of Evolved psychological mechanisms. (Massive modularity hypothesis)

The specificity, complexity, and numerousness. … In general, the more complex the mechanism, the greater the number of response options there will be. … With each new mechanism that is added to the mind, an organism can perform a new task. … This leads to a conclusion contrary to human intuitions, which for most of us holds that having a lot of innate mechanisms causes behavior to be inflexible. In fact just the opposite is the case. The more mechanisms we have, the greater the range of behaviors we can perform, and hence the greater the flexibility of our behavior.

Beyond Domain-Specific Psychological Mechanisms. … Some evolutionary psychologists, however, have recently argued that in addition to these specific mechanisms, humans also have evolved several domain-general mechanisms. Examples of proposed general mechanisms include General intelligence, concept formation, analogical reasoning, Working memory, and Classical conditioning.

—p53-58, Evolutionary psychology