This paper will attempt an analysis and evaluation of the meta-theory of evolutionary psychology from the framework of Rychlak's (1990) fundamental dimensions of theoretical orientation. There are some who believe that an evolutionary approach will become a popular paradigm in the social sciences. Some of the implications stemming from the analysis of this theoretical approach will be discussed.
Evolution by selection is the most viable scientific account for the origins and functions of complex physical organs such as the eye and brain. It would thus be quite reasonable to apply an evolutionary analysis to the complex mental and behavioral phenomena studied by psychology. The analyses of features in evolutionary terms would explain cognitive and behavioral mechanisms by their functional adaptiveness. The current psychological paradigm entails the description of phenomena, the production of empirical generalizations, and the explanation of these phenomena in terms of proximate causes, instead of ultimate causes (Buss, 1996).
An evolutionary approach may also be useful in making connections between a variety of structurally disparate phenomena, as well as serve to further integrate psychology with the accumulated understanding in the other fields of science. One may recognize that integration is one of the functions of theory, and truly insightful knowledge will cover more than one realm (Rychlak, 1990).
Rychlak (1990) has described five dimensions on which a theory may be described. These dimensions are: Abstraction, realism versus idealism, objectivity versus subjectivity, introspection versus extraspection, and formal versus informal. Each of these dimensions may by examined independently, although the objectivity-subjectivity dimension is often confused with realism-idealism.
One may picture a ladder of abstraction, where theories and hypotheses could be ordered from metaconstructs to the microscopic. Molecular concepts are precise, while molar concepts are global and leave out details in order to capture the general meaning.
Evolutionary psychology is multiordinal. The meta-theory is the overarching theme of selection, while more specific theories and hypotheses can be derived from various functional adaptations, which selection acts upon. There are two main processes in evolution, natural selection and sexual selection. Whereas natural selection determines evolutionary fitness with characteristics related to survival, sexual selection is the process that determines who is able to successfully reproduce. In the language of evolutionary theory, the probability that an individual will successfully reproduce by passing on her or his genes is called fitness. Classical, or Darwinian fitness bases an individual's reproductive success in passing on traits to future generations through direct decedents.
Inductive reasoning moves up the ladder of abstraction, for example, building a theory of interpersonal interaction to explain observable phenomenon. Deductive reasoning could derive predictions of observable behavior from a general theory about how people relate to their ecological environment. The hypothetico-deductive method makes use of both of these forms of reasoning (Rychlak, 1990). One may form a hypothesis based on a possible solution to an environmental problem or issue. This would then be tested through empirical observation. At the same time, researchers could take anthropological or other previously collected data and develop an interpretation based on some functional adaptation. The tendencies underlying this adaptation must be present cross-culturally, if it is truly inherent, although the expression may vary depending on the cultural and environmental context.
There is so much evidence for "theory" of evolution, that the generalities are universally accepted by scientists today [aside from "creation-scientists," who bicker about polonium halos and the archaeopteryx], since there are no real competing scientific theories for the origin of the species. At the same time, more specific theories of how organisms have adapted to survive and reproduce are open to debate. Just because a hypothesis has an evolutionary basis for the explanation of behavior does not make it correct. There may even be competing explanations for certain phenomena, each with a basis in functional adaptiveness. These theories will also be selected from, since psychology claims to follow the method of hypothesis-testing.
Evolutionary psychology falls near the realist end of the realism-idealism continuum. At the idealist extreme, it makes no difference whether or not there is a concrete reality. An idealistic theorist would claim that there is no external world apart from the perception and cognition of the perceiver (Rychlak, 1990). On the other end, the realist would claim that our perceptions map a concrete reality, and this reality would best be understood by precise, accurate, and narrow definitions. Knowledge would be abstracted from the delineation of reality. The idealistic could counter that knowledge is primarily an act of creation, and that one's perceptions of reality are influenced by preconceptions.
Since evolutionary psychology focuses on humans' adaptation to their natural environment, it takes the position that the world we perceive exists, entirely independent of our laments for more benevolent conditions. In fact, the cognitions and perceptions of the individual organism may vary, as long as they lead to behavior which ensures survival and reproduction. This will been seen in the evolutionary approach to "altruism," in the discussion of the extraspective-introspective dimension.
Of course we should recognize one criticism from an idealistic perspective, that ideas may have an affect on how we perceive reality, and thus ideas must be taken seriously. Evolutionary psychologists may wear a pair of Kantian spectacles, tuned to see functional adaptation. From an evolutionary perspective, all common human motivational and affective states would have, on average, served to increase the survival of our ancestor's individual genes (Kendrick, 1991). This means that even something which would seem maladaptive for the individual, such as anger or depression, would be beneficial at a larger level since the ability to experience these affective states somehow lead to behaviors which improved our overall chances for survival.
One could speculate on situations where a negative affective state would lead to adaptive behavior. The important point to keep in mind is that if a trait has been selected for, there must be some genetic influence on the expression of the behavior. Kuo, a behaviorist, asserted that all behavior of humans and other animals is completely determined by the stimulus (1928). Evolutionary theorists do not take the analogous position with genetic influence.
Philosophers and certain social scientists continue to popularize the "nature-nurture" debate. In evolutionary psychology, as well as biology, this is seen as a false dichotomy. Genes are expressed in accordance with the context of the environment. Even height, a feature with a strong genetic component, will be influenced by the amount of nutrition one receives during development. The heritable genetic component may be seen as setting the parameters for the expression of a "trait," while the context of the environment sets the precise location on that continuum.
The position on the objective-subjective dimension theory is implicitly addressed by the very existence of a discussion of evolutionary psychology in the literature and in this paper. The objective perspective holds that a theoretical concept can be transmitted from one person to another, and it will be understood by the receiver. This does assume that the receiver has the ability to understand such terms, based on his or her experience, including the provision of meaning in terms understood by him or her. Of course, it is assumed that this begging question is answered in the very existence of language, which could not exist without shared meaning.
A more subjective perspective would hold that our abstractions and relations between them are somehow private, difficult or impossible to circumscribe, and cannot be generalized beyond the behavior of the abstractor in question (Rychlak, 1990). This is not the case with evolutionary psychologists, who would hold that anyone with a functional intelligence could understand the basic concepts, when given an education on the material. There may be a great deal of background material to explain to someone living in an Amazonian hunter-gather tribe, however, the knowledge common to industrialized societies is often successfully introduced into other cultures. The tribal member may even more readily recognize evolutionary processes, considering his or her closer ties with the natural environment than those of most citizens in industrialized nations.
Elements of the objectivity-subjectivity dimension form a bridge into the discussion of the extraspective-introspective dimension. Nomothetic study holds that a theoretical abstraction can be generalized to several members of a given class. Idiographic study emphasizes the uniqueness of personality manifestation (Rychlak, 1990). Evolutionary psychology's nomothetic approach ties in with its extraspective perspective, the observational standpoint from which the theoretical abstractions are discussed. The dimension of perspective has the potential for generating provocative issues for discussion. Introspective approaches, such as Freudian psychoanalysis, take the perspective of the object of study (Rychlak, 1990). Interpretations are based on this first person perspective, not from the experiences of the observer. Introspectionist methodology, also championed by structuralists like Titchner, fell out of favor after Watson and others attempted to reject all forms of introspectionism in psychological theory.
The behaviorists sought to replace introspection with an extraspectionist emphasis on experimental design. The extraspective perspective defines abstractions from the vantage point of the observer, regardless of the point of view of the object of study (Rychlak, 1990). Functional adaptations are mechanisms which organisms use to solve "problems" in their internal and external environment.
Unlike in ideographic study, anecdotes from one specific individual may add a qualitative dimension to phenomena, but they are not the focus of study. In fact, the "person" is not even the currency of the selection, our bodies are only vehicles for reproducing genes. This can be illustrated with a discussion on the psychological concept of "altruism" and the evolutionary concept of inclusive fitness.
According to classical fitness, members of a species that sacrifice their resources for the benefit of others will have fewer successful offspring, on average, and hence an inherent tendency towards this behavior would be selected against. Hamilton (1964a) expanded the basis of reproductive success to include relatives who become ancestors of offspring with similar genetic material. Hamilton's inclusive fitness theory leads to the prediction that natural selection will favor those characteristics which cause a person's genes to be passed on, regardless of whether or not the person is the actual direct ancestor. By assisting in a time of need, one would help his/her relative become an ancestor of offspring with similar genes.
A genetic influence on the tendency to help relatives would increase the population of genes that promote giving assistance to relatives. This would be adaptive from an evolutionary perspective, since it is not the survival of the organism that is critical for natural selection, it is the survival of the genes. Despite the catchphrase "survival of the fittest," the ultimate criterion which determines whether an "altruistic gene" is spread is whether it benefits the gene itself, not whether it is of benefit to the bearer of the gene (Hamilton, 1964b). The alarm call of a bird probably involves a small extra risk to the individual making it by rendering it more noticeable to the approaching predator, but the consequent reduction of risk to a nearby bird previously unaware of any danger must be much greater, and an alarm call often warns more than just one nearby bird (Hamilton, 1964a).
One area of psychology which could address kin selection is the research on helping and altruism. Philosophers have pondered the existence of altruism throughout the ages without any clear resolution (Cialdini, Brown, Lewis, Luce, & Neuberg, 1997). It is notable that "the golden rule" is found in many systems of proscriptive norms, such as Christianity, Judaism, Hinduism, Taoism and Confucianism (Shroeder, Penner, Dovidio & Piliavin, 1995). This would seen to imply that helping others when the need arises is an action encouraged by the rules of society. The debate continues among social psychologists over whether "true altruism" exists. While some argue that empathy for others leads to altruistic actions (Batson, Sager, Garst, Kang, Rubchinsky & Dawson, 1997), others believe that conditions which lead to empathic concern also lead to a greater sense of self-other overlap. Helping others under these conditions would not be selfless but instead is directed towards the self (Cialdini et al., 1997).
In studies conducted by Cialdini et al. (1997), it was found that as relationship closeness increased, so did empathic concern for a needy other. The amount of helping which was costly to the donor decreased with an increasing distance of relationship. That is, helping a family member was more likely than helping a close friend, which was more likely than helping an acquaintance, which was more likely than helping a near stranger. In Batson's studies (Matthews, Batson, Horn & Rosenman, 1981), 71% of the variance in the amount of empathy is estimated to be accounted for by genetic relationship (Rushton, 1991). This strongly suggests the existence of a kin selecting influence on empathy.
The main distinction between the two perspectives is the definition of who or what is assisted. For the altruist advocate, that entity is another individual. An evolutionary theorist would consider the genetic information in that individual (which may be similar to that of the donor's) the ultimate benefactor. Consistent with evolutionary theory, felt oneness could arise as a consequence of attachment-related cues (kinship, friendship, familiarity) that signal relatively high genetic commonality. At the same time, an action that benefits the genes could be "altruistic" in terms of the cost to the helping individual. It is possible that the mechanism through which helping operates is the experience of empathy for another.
The implication is that ultimately, a great deal of influence on our behavior stems from predetermined patterns of survival and reproduction. There may be a reluctance in segments of the psychological community to ascribe behavior to something other than "free will," or consciously calculated decisions. This was one of the reactions to Behaviorism, which holds that an organism is programmed by the reward and punishment contingencies of the environment. One of the early behaviorists, Watson, saw people as a tabula rasa that could be modified to fit any chosen mold. The Humanistic orientation of many modern psychologists values the individuality of every person and holds the notion that people are in control of their own destiny. For many, it would be insulting to suggest that a considerable amount of the actions they perform have their ultimate causality in inherent adaptive tendencies. These tendencies could be expressed at the conscious or subconscious level, as long as the outcome is generally adaptive.
The discussion of the formal-informal dimension of theory is crucial when examining an evolutionary perspective. There is a great deal of historical baggage from those who have used arguments with a pseudo-evolutionary basis to advance their political agendas. The formal aspects of theory are the explicitly stated systematic union of all the loosely joined tenets, hypotheses and validated facts into a consistent, interdependent unity (Rychlak, 1990).
Since the formal aspects of theory are systematic, they may become crystallized, and lose the capacity to generate new hypotheses. The basic theories of selection are currently crystallized (unless another Hamilton induces a new paradigmatic shift). However, the multiordinal nature of evolutionary psychology allows for much speculation about specific areas of adaptation. The field of social psychology (such as concentric in-group/out-group effects) is rich with phenomena suitable for evolutionary interpretations.
Informal theory has not been explicitly stated, it often goes unrecognized by the theorists. While informal theory does not have the implicit goal of formalizing a logically consistent and mutually interdependent body of knowledge, it does have an impact on the nature of the data chosen for the study, the kinds of constructs, and the kinds of theoretical assertions made (Rychlak, 1990).
Since there may be preconceptions about evolutionarilly based theories, it would be useful to make clarifications on some of the perceived implications which may be considered informal assumptions. Sometimes evolutionary (and biologically) based theories are not given proper consideration because of the perceived political implications. As a scientific discipline, evolutionary psychology is primarily concerned with describing and explaining what exists. Political orientations also describe and explain what exists, but in addition, they are concerned with what should exist. G. E. Moore described the "naturalistic fallacy," deriving the "ought" from the "is," in his book Principa Ethica published in 1903 (Nitecki, 1993).
Social psychologists concur that activation of stereotypes with an evaluative component is automatic, it precedes conscious control and happens whenever the discriminating features of a group are present (Tesser & Martin, 1996). Still, this does not justify prejudice against stereotyped groups. Just because something is seen as "natural" does not make it morally correct. We are living in a vastly different world than our ancestors, and the tendencies we have are not necessarily appropriate in the present context. Understanding inherent psychological characteristics derived from evolution will help us to deal more effectively with the ones that are maladaptive in our modern, technologically advanced society.
Many social scientists have thought of evolutionary theories as derogating the value of women. These critics have focused on narrow, male-oriented definitions of power. Individuals expressing this view may not have realized that a female's choice of mates is generally more important than the male's choice in driving sexual dimorphism within a species (Kendrick, Trost, & Sheets, 1996). Since women have to make a greater obligatory investment in offspring though gestation and infant care, they are more choosy about whom they are going to mate with (Buss & Malamuth, 1996). This universal preference has selected for men who are able to provide for potential offspring through the resources they are able to devote. Men then have to be more competitive with each other for access to women. This has created a strong demand for men who are able to provide valuable resources, resulting in the characteristics of assertiveness, aggressiveness, and sensitivity to hierarchy found in men.
Two assumptions which are present have to do with the nature of human evolution. Although these are occasionally stated explicitly, they form a base of informal theory from which implications may be drawn. One of these assumptions is that humans evolved in an ancestral environment that bears little resemblance to our modern world.
There is no question that human culture has changed tremendously in the past few centuries. The vast majority of individuals living in industrial and post-industrial nations lead fast paced lives, and encounter a wide variety of situations and experiences. We are surrounded by technological advances and exist on an organizational scale far more complex than anything in past history. Archeological evidence reveals that humans lived in nomadic or semi-nomadic groups of twelve to fifty individuals throughout the bulk of our evolutionary history (Diamond, 1992).
Since our technologically advanced environment has existed less than five generations, it is just a blip at the end of the time line of humanity. We have had scarcely any time to adapt to this drastic change of context in evolutionary terms. At the same time, our previously acquired adaptations have influenced the way we shape our environment. For example, people prefer enclosed spaces that are visibly and audibly inaccessible to others, but allow them to maintain awareness of their surroundings. This concept of "defensible space," which was critical for habitat selection, has made a great impact on modern architecture and landscaping (Davis, 1984).
The notion that we are adapted to a drastically different environment than the one in which we currently live has implications for the research approach to phenomena. Evolutionary psychologists may only be confounded if they seek adaptations in our current context. While many inherent tendencies remain functionally adaptive, others have curious expressions in our cultures. An example of the latter can be seen in current expressions related to the process of sexual selection.
Sexual selection has two components, intrasexual competition and intersexual selection. Intrasexual competition consists of contests between members of one sex, where the winner of the contest gains preferential access to members of the opposite sex (Buss, 1996). The prototypical example of intrasexual competition is buck deer locking horns in combat during the mating season. The winner of the bout gains the territory and access to the females within it. The loser goes home with a broken horn. This process continues year after year (Darwin, 1871).
Intersexual selection involves both sexes. If members of one sex have a consensus about the desirable characteristics of the opposite sex, then those individuals with the desired characteristics will have a mating advantage. One example is the size and decorative coloration of feathers seen on many male birds. It is hypothesized that the underlying reason why female birds find a male peacock's tail feathers attractive is their indication of the survival ability of male birds. The feathers would not only be noticeable to females, but also to predators and a hindrance in movement, etc. It would seem easier to survive without this costly display, the females of the species usually possess coloration that blends in well with the features of the habitat. The birds that are able to survive with this handicapping display must also have some characteristics that would be valuable for the female's potential offspring to acquire (Darwin, 1871).
Humans do not have brilliant plumage, so we must have some other criteria for sexual selection. In a study of 37 cultures on six continents and five islands, Buss (1989) found that women value prospective male suitors on a cluster of characteristics related to resource potential: good financial prospects, ambition, industriousness, older age, and emotional maturity. On the other hand, men value potential female partners in terms of fecundity, the ability to produce and care for children. This is expressed in a preference for youth and physical attractiveness (Tesser & Martin, 1996). Cunningham (1986) found that "baby face" features, i.e. large eyes and a small nose, were consistently positively correlated with attractiveness in women, perceived fertility, and perceptions of few medical problems.
Another salient characteristic in humans is the ratio of the circumference of the hips to the waist. Before puberty, men and women have a similar distribution of fatty tissues, but afterwards women have a greater hip-to-waist ratio. Singh (1993) noted that a larger hip-to-waist ratio was associated with better health status and greater reproductive capacity, and used archival data to examine the measurements of Miss America Pageant winners and Playboy centerfolds over the past fifty years. Singh found that a small waist set against full hips was a consistent feature of female attractiveness, while bustline, overall body weight, and physique varied over the years.
In our ancestral environment, gender specific intersexual attraction cues served as a basis for differentiating potential mates. These cues were fairly reliable, since the ancestral environment was much less forgiving than the one most of us live in today, the mortality rate was much higher for infants and adults alike. The attraction cues were a good indicator of whether someone was able to successfully reproduce and/or provide for and raise offspring. In industrialized societies, reproductive potential now far surpasses the estimates indicated by attraction cues, since these cues did not have to account for modern health care, shelter and nutrition.
We are still guided by these attraction cues today, although our technologically advanced environment has produced a spiral of increasingly stringent definitions of what qualifies as attractive. People are no longer limited to the few hundred individuals (of varying ages and reproductive potential) that would be encountered during the lifetime of a hunter-gatherer. Comparisons can now be made between thousands of individuals, and those which become media representations are often subjected to a high degree of selection. Today we are bombarded with images of "ouliers" which set the "standards" for attraction.
Another informal assumption of evolutionary psychology is the place of Homo sapiens in the web of life. There is a long historical precedent for a reluctance to consider the "animal nature" of humanity. For example, the worldview popular in Europe during the Middle Ages places humanity on a "Chain of Being" only one step lower than the angels. It is still common to hear a linguistic distinction made between "humans" and "animals." For a number of reasons, even today some are constantly searching for objective evidence that humans are somehow uniquely special and, therefore, "better" than the other members of our Kingdom.
This view may be enlightened by genetic research finding that humans share more than 98% of their genetic code with chimpanzees. In fact, chimpanzees are more closely related to humans than they are to any other primate (Diamond, 1992). Still, many choose to focus on differences rather than similarities. Even among social scientists, it would be disturbing for many to find that our ultimate concerns are survival and reproduction.
At the other extreme, many behaviorists have seen humans as interchangeable with other animals with regards to psychological research. This was based on a Lockean model of animal nature, Thorndike saw the study of "simpler" animals as a way to understand the behaviors of humans, which follows the same rules despite a greater degree of complexity. The study of animal learning had become so far removed from basic biological concerns by the late 1960s, species specific learning mechanisms were seen as a challenge to the viability of the entire enterprise (Galef, 1998). This approach fails to take into account the context specificity of adaptations, the species are not necessarily adapted to the same environment.
Rychlak (1990, p. 37) cautions that "we should study rats to learn about rats and man to learn about man." For an evolutionary approach, studies on a variety of animals would be important. The intent would not be to generalize the results of laboratory experiments from other animals to humans (or vice versa), but rather to compare how different organisms respond to similar problems and situations in the natural environment. Adaptional homologues and analogs could be examined to find general patterns and unique solutions. The resulting framework may even suggest "novel" solutions to problems currently faced by humans.
Evolutionary psychology can also be analyzed in the framework of Aristotelian causality. This will entail delving into the biological and physical sciences which explain the mechanisms of evolution by selection found in the organism and the environment.
The genetic code was not discovered until the 1950s, Watson and Crick's description of deoxyribonucleic acid was nearly a century after Darwin's Origin of the Species and Mendel's observations of inherited traits in peas. The molecules which comprise this genetic code are in themselves a material cause, and act as an efficient cause in the formal cause pattern of replication and reproduction. DNA is the proximate origin of the efficient cause which shapes organisms at the cellular level. Through transcription and translation, genetic material is the formal cause blueprint for an organism's structure and function, which is also shaped by efficient causes from the environmental context.
The chain of efficient cause events that lead from genetic code to influences on behavior are largely uncharted. Even when the Human Genome Project eventually sequences the entire human genotype, it is not likely that most complex behaviors will be reduced to deterministic genetic instructions. This will be a productive area for future research, since the complex relationship between genes, environment and behavior offers many directions for study.
The environmental component of selection can be seen as the efficient cause that determines which characteristics are adaptive in their present context. Individuals also participate in the efficient cause process, through their actions relevant to survival and reproduction. In a way, the efficient cause pattern is less like a chain than a complex web of influence.
Evolutionary theory contains a final cause. It is noted that the will of the individual has not yet been mentioned. This is an extraspective teleology, as genes are not considered to have a point of view. This fourth Aristotelian cause often contains the answer to questions of meaning and purpose. Thus, evolutionary theory provides an answer to one of philosophy's most basic questions.
The purpose of life is to ensure the continuation of life. Our bodies are temporary vehicles for a process that has occurred for billions of years. From viruses to human beings, the preservation and propagation of genetic code is the ultimate goal of an organism's design.
In this case, the designer is blind to the patterns it creates. The current species are the result of billions of generations of organisms, which have gradually been shaped into their current state by the processes of selection. When such an explanation is postulated, some may try to trace the network of efficient causality to an origin. This puzzle in Aristotelian logic has been previously been answered with the concept of the unmoved mover, an entity which starts the entire process in motion. This, of course, begs the question of where the unmoved mover originated.
The unmoved mover of evolution could be considered to be the first molecules which began replicating themselves in the "primordial soup." Scientific explanations for the origin of genetic code cite the creation of amino acids from basic chemicals which were common in earth's ancient existence, along with electricity. The origin of the substance of the earth is beyond the scope of this paper, since the molecules are being discussed only with regard to their role in a biological and psychological context.
Like the fractal patterns in mathematical chaos theory, out of simple building blocks came more complex and elaborate patterns. Only after these patterns had been established did the "directions" come from the top down, instructing the production of another organism.
The genetic final cause carries a blueprint, as well as an intention. The goals are proximate, the ends for which this process occur simplistic. Evolution is not directional, Darwin has compared it with a bush that grows in every direction. Some of the branches are successful, some get pruned. This implies that human intelligence exists because increasing levels of mental ability allowed our ancestors to form better solutions to problems in their environment. The structure and likeness of our bodies stem from a sequence of modifications, each adaptations to environmental changes across the millennia.
This analysis of evolutionary theory raises many philosophical and psychological issues. From a psychological perspective, the secondary importance of the individual to genetic material may be a strong concern. The cognitive and affective aspects of the individual in this process is not ignored by evolutionary theorists, some have taken cognitive approaches to research involving evolutionary hypotheses. By the inherent nature of evolutionary adaptations, a nomothetic approach is necessary.
From a philosophical perspective, the evolutionary explanation for the purpose of life may be persuasive, while leaving a sense of emptiness, as if one has finally solved a puzzle only to be disappointed by the simplicity of the solution. One may argue that an intention exists only when there is the conscious awareness of a goal. Thus, those who are not aware of the underlying reasons for many of their cognitions and emotions may focus solely on proximate intentions. These proximate intentions have a pervasive impact in our societies, such as the ubiquitous concerns about sex.
A thorough understanding of evolutionary psychology, including the issues raised here, may become of increasing importance. Adaptionist theory has been surprisingly dormant in the social sciences throughout most of this century, possibly due to the damage done by those making misinterpretations to further their own goals. Social scientists would be well advised to become aware of the implications of evolutionary theory in their field, since they would be in a better position to critique misunderstandings, debate on genuine theoretical conflicts, and look for functional adaptations in their own topics of study.
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