"Supernormal stimulus" (SNS) was developed in the 1930s by Lorenz and Tinbergen in ethological research on sticklebacks' aggression and gulls' feeding behavior (Gould & Gould, 1997; Hess, 1962). The greater the contrast with "natural stimuli," the greater the capacity for the SNS to compete with natural cues. Even though the concept was first applied to ethologist-produced stimuli, the methods revealed the power of specific cues that are larger, brighter, and perhaps livelier. (1) While the concept appears less frequently today, the processes it reflects could account for phenomena in several different realms including sexual selection, speciation, orthoselection, and mismatch. (2)
Sexual selection Generally, secondary sexual traits in the male are considered to be evolved as a consequence of female preferences; enhanced physical or behavioral displays are thought to advertise good genes or promise healthy sons (Dawkins, 1989). However, the correlation between having a larger tail and being healthier could be limited because a bird with a large tail and producing weaker sons would likely drift towards extinction. There may be no direct causal relationship between the magnitude of a secondary sexual display and children's having more than an average survival fitness. It could be that peacock or widowbird tails are the essential cues for the hen - through her own psychological adaptations - both to target a male of her species and to regulate the intensity of her attraction. Her sensory mechanisms may operate in a manner similar to those of sticklebacks and gulls ... the larger the display, the more effective it is to her in triggering mating responses. (3) A dad with a more colorful tail may produce children with colorful tails, who because of their color, are themselves more likely to mate. A positive feedback loop is established and rapid changes occur, limited only by homeostatic costs (Bateson, 1963).
Speciation Hess (1962) remarked that fixed action patterns appear to be relatively slow changing in closely related species except in the domain of sexual selection. Behavioral traits that function as releaser stimuli change far more rapidly and may act along with changing physical traits to create a mating distance between former kin. (Indeed, the traits may change more rapidly because they take on an SNS role.) It raises the possibility that animals classed as different species retain the capacity to interbreed but do not act on it because of differences in sensory coding for mate selection.
Orthoselection The apparent progression of a species across many generations in a consistent direction is another domain. Systematic changes over generations in a particular trait give the appearance of goal-direction or teleological purpose. This seems especially true in the absence of known selective pressures. Species often get bigger with generations. Again, the sensory mechanisms associated with SNS could operate to produce larger individuals as well as larger traits.
Mismatch Many refer to a gap between our present culture and our home environment, our Eden (Glantz & Pearce, 1989; Wright, 1994). (4) We are alleged to hurt in areas where we changed our culture but not ourselves. Mismatch accounts, perhaps, for some depressions, anxiety, and other personal distress. However, if our culture is mediated via our Psychological Adaptations as argued by Barkow et. al (1992), mismatch should be less extreme. Blaming mismatch on agriculture or technology is not particularly satisfactory even though we didn't have much technology or agriculture when we were youngsters. (5) While we appear to have a lot of "distortions" in our culture, they may be functional if on a smaller scale. Thus, mismatch seems more a function of our SNS preferences for larger or more conspicuous things (possessions or organizations) interacting with specific behavior traits linked to psychological adaptations.
The combination of our preferences for SNS and our Psychological Adaptations produces a range of things that once enlarged do not work so well as they did when smaller. Examples include residential institutions (prisons, hospitals, nursing homes, housing projects), welfare, Medicare, unions, churches, school districts, our towns and cities, and health care networks. Our institutions, our tools, our systems for caring for one another are expressions, perhaps cancerous, of sensory mechanisms drawing us towards the larger, the louder, the faster, the stronger. It's as if we make our own alphas when we form organizations or buy things. Take a sensory mechanism, mix it with any adaptation, throw in abundant resources and get a distortion with a bucket of mismatch.
Lateral Inhibition The bias in sensory mechanisms is a function of the two basic processes, excitation and inhibition. The former triggers a response chain, the latter attenuates the initial sequence as well as competing reactions in parallel receptors or weaker motivational systems. The more powerful the trigger, the greater the suppression of competing activity. Increasing resources or dispersal of output allows another excitation phase. The resulting oscillation applies to a range of phenomena spanning Beloussov-Zhabotinsky reactions up through amoebae and neurons, through the economic growth and decay of urban areas and perhaps star systems (Goodwin, 1994). The basic system is refined when the inhibitory function allows the suppression of competing activity, whether of neurons or of species. The term "lateral inhibition" applies. The phenomenon of lateral inhibition leads to contrast effects in all sensory modalities (Von Bekesy, 1967), to the absence of distraction, perhaps to task persistence, and eventually, to thinking and the Executive Functions. (6) Because lateral inhibition allows an increase in focus or of differences between similar events, it gains functional properties identical to the Darwinian concept of "diversity driven by competition." Thus, with SNS in combination with LI we summarize dynamic relationships in a highly general manner. It doesn't matter whether we plug molecules or civilizations into the statements, the relationships remain the same. SNS allows us to use a single mechanism on events from phototropisms to larger physical sizes and perhaps to symmetrical features and livelier temperaments. The process accounts even for bigger tail fins on our darn cars, for larger engines, and for faster speed in excess of what we need to travel safely. No one talks about car evolution and orthoselection but they could. LI leads to differentiation, to diversity. This concept also applies at nearly any content level.
T4T Exacerbation arises from our ESS for handling reciprocity, the strategies of Cheater and Sucker (Dawkins, 1989). "Generous Tit for Tat" has been demonstrated as an ESS resilient to invasions by cheaters. However, T4T only works in a series of exchanges between conspecifics. The absence of a continuing, personal relationship lets Cheaters (insurance swindlers, auto dealers, real estate developers) thrive. Thus, T4T is disrupted by large groups and populations with high individual mobility. It can also be disrupted by rotating staff, whether physicians or letter carriers. Staff rotation and the absence of repeated contact between the same individuals encourages loyalty to the company (if ever that relationship is a continuing one) rather than to patients or customers. Thus, organizational interests develop that are contrary to those of individual clients because the recurring relationships are those within the organization.
As organizations grow, oscillation between Cheater/Sucker is slowed. There is less inhibitory effect from patient feedback onto the organization's behavior and Cheaters increase on both sides of the relationship. Practitioners cheat and cover for each other; patients cheat and see it as their rightful due. They both form alliances with each other and cheat the insurer.
These shifts in social (reproductive?) advantage for Cheaters or T4T has a functional identity to the oscillation seen at cellular or bacterial levels. Action creates its own negative feedback and shuts itself down unless there is a large input (lots of customers) and little inhibition (no costs to the organization for mistakes). An inhibitory phase, patient surveys elicited by competition between organizations reinstates concern for the patient. (7)
Finally, any of the above can be aggravated by manic traits, an excess of the alpha stuff as reflected by too much drive for territory, for standing, for resources, for sexual choices. The urge to take something big and make it bigger can eventually betray us. (8) Thus, H&G minds build H&G cultures, including ones with mismatch. (9) And, by this analysis, even peacock tails become an example of it.
1)This essay has also been submitted to ASCAP (Across Species Comparisons & Psychopathology) Liveliness may be a more powerful attractor than size and color. Our sensory mechanisms are generally cued to react best to stimulus change. Thus, the bouncier the girl, the more we look her way. The faster the male's pace, generally the less depressed he is and possibly the more attractive. I'm not aware that anyone has examined liveliness as an attractor in its own right although Hess (1962) refers to Tinbergen's description of Fixed Action Patterns as also having cue properties and filling the role of SNS. Even the choice of study material suggests a preference for SNS in ethologists; they usually study increases, not decreases, in the amplitude or duration of a creature's behavior.
2) Another domain is K-Selection, associated with stable environments carrying near their capacity for a particular species. K-selection is characterized by more cooperation, less altruism, fewer children, greater parental investment, and LARGER children than under r-selection conditions. Sensory processes for SNS could account for at least one aspect of K-selection. SNS could be a fundamental module in a Grand Theory of Everything so I'm puzzled as to its relative absence in discussions of mate selection as well as other evolutionary processes. Gould & Gould (1997) mention it for several pages near the end of their compilation but little else is made of the phenomenon. Mayr (1976) doesn't mention it at all. Certainly, the other mechanisms and processes that people have laboriously defined for sexual selection, orthoselection, and K-selection also have merit. However, the simpler and more general concept is that of sensory mechanisms guiding preferences largely on the basis of contrasts in size, color, and physical activity.
3) The lopsided sexual nature of these phenomena is troubling. Males will copulate with most any female while the females of many species, more selective themselves, can wear just any frock and catch a guy. But, human males, despite their copulatory zest, appear to have their own preferences for intelligence, body shape, clear skin, and symmetrical features. These preferences seem most persuasive when the anticipated partnership is to be sustained (Buss, 1994). It could be that male birds also have preferences but our own psychological adaptations aren't sensitive to the relevant cues. We need a peacock to to judge the color, vocal quality, symmetry, and liveliness of a peahen.
4) "Mismatch" has some distinguished fathers besides Rousseau. JBS Haldane (1928) referred to it in an essay on "Food Control in Insect Societies." Psychological Adaptations (Barkow, et al., 1992) promise to give a higher level of detail as to the nature of "mismatch" so that it becomes situational and plural.
5) Take some bees and a lot of flowers and get more bees. If you add still more flowers and transitorized honey scoopers, you likely will get still more bees rather than depressed or bizarre ones.
6) Bronowski (1977) argued that response inhibition instills a necessary delay in reflex sequences, a delay that becomes the foundation for planning, language development, emotional regulation, and the cognitive processes of analysis and synthesis. Barkely (1977) picked up on this model and applied it to a range of deficits seen in the same domains in ADHD children and adults.
7) Managed Health Care may be shifting its ESS. There are many recent advertisements about "they care." Blue Cross lately sends birthday cards to women approaching age 50. The cards say, "Happy Birthday, go get a mammogram." Computers may eventually make it possible for an organization to serve a huge audience and remember all the birthdays and names of the kids. A recently deceased politician was immensely popular and said to know the parents, children, aunts, uncles and cousins of some 30,000 local families. "Knowing" someone is the first step towards maintaining an alliance. Likewise, zoning codes and buyers protection plans are inhibitory reactions to initial r-selection conditions. As resources diminish, "cooperation" (an aspect of lateral inhibition?) increases so long as population is still below the carrying capacity of the environment. Liberal political beliefs, the NHTSB, and Buddhism are more likely in Cambridge or Los Angesle than in central Pennsylvania. A gradual onset of diminished petroleum availability should increase the popularity and enforcement of affiliative belief systems. A rapid onset should elicit the desperate conditions of a behavioral sink.
8) There's a saying from some Greeks, I believe. "The gods first make proud those whom they wish to destroy." There is a good argument that manic characters are adaptive in r-Selection but maladaptive in K-Selection.
9) We could discourage Cheater tactics if we decentralize providers, consumers, and organizations. Smaller groups could exist in the middle of huge populations for most social functioning and with computer support, develop greater efficiency when handling diminished resources such as food or petroleum. It is likely that selection pressures will build for people to function smoothly in hives such as McDonalds or Toyota assembly lines. (Does McDonalds meet criteria for "eusociality," defined by Wilson (1980) as the "cooperative care of the young, reproductive division of labor with the sterile working on behalf of individuals engaged in reproduction (aka "management), and overlap of at least two generations contributing to colony labor"? Probably.)
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