Evolutionary Psychology - Research Methods

Research Methods

Evolutionary theory is heuristic in that it may generate hypotheses that might not be developed from other theoretical approaches. One of the major goals of adaptationist research is to identify which organismic traits are likely to be adaptations, and which are byproducts or random variations. As noted earlier, adaptations are expected to show evidence of complexity, functionality, and species universality, while byproducts or random variation will not. In addition, adaptations are expected to manifest as proximate mechanisms that interact with the environment in either a generally obligate or facultative fashion (see above). Evolutionary psychologists are also interested in identifying these proximate mechanisms (sometimes termed "mental mechanisms" or "psychological adaptations") and what type of information they take as input, how they process that information, and their outputs. Evolutionary developmental psychology, or "evo-devo," focuses on how adaptations may be activated at certain developmental times (e.g., losing baby teeth, adolescence, etc.) or how events during the development of an individual may alter life history trajectories.

Evolutionary psychologists use several strategies to develop and test hypotheses about whether a psychological trait is likely to be an evolved adaptation. Buss (2011) notes that these methods include:

Cross-cultural Consistency. Characteristics that have been demonstrated to be cross cultural human universals such as smiling, crying, facial expressions are presumed to be evolved psychological adaptations. Several evolutionary psychologists have collected massive datasets from cultures around the world to assess cross-cultural universalty.

Function to Form (or "problem to solution"). The fact that males, but not females, risk potential misidentification of genetic offspring (referred to as "paternity insecurity") led evolutionary psychologists to hypothesize that, compared to females, male jealousy would be more focused on sexual, rather than emotional, infidelity.

Form to Function (reverse-engineering – or "solution to problem"). Morning sickness, and associated aversions to certain types of food, during pregnancy seemed to have the characteristics of an evolved adaptation (complexity and universality). Margie Profet hypothesized that the function was to avoid the ingestion of toxins during early pregnancy that could damage fetus (but which are otherwise likely to be harmless to healthy non-pregnant women).

Corresponding Neurological Modules Evolutionary psychology and cognitive neuropsychology are mutually compatible – evolutionary psychology helps to identify psychological adaptations and their ultimate, evolutionary functions, while neuropsychology helps to identify the proximate manifestations of these adaptations.

Evolutionary psychologists also use various sources of data for testing, including experiments, archaeological records, data from hunter-gatherer societies, observational studies, self-reports and surveys, public records, and human products. Recently, additional methods and tools have been introduced based on fictional scenarios, mathematical models, and multi-agent computer simulations.