Tell myself this is all crazy but GrandDad keeps happening. I was schooled not to believe in genetic effects, whether on personality or on specific behaviors. In my lifetime, it's become acceptable to see temperament as genetically influenced.
My dilemma is making a responsible interpretation of the fine details, the idiosyncratic coincidences that leap to awareness, like one of those paintings of apparently random dots that build sailing ships if you look slightly past the surface of the picture.
The latest ... Pete is about 14, nastily rude and threatening regularly to his mother and weekly to his father. There has been talk of placement, foster care, and using the courts. Yet, much of the time Pete is polite and cooperative with strangers and with his teachers, unless one of them strikes him as being unfair. Certainly, Pete fits into the mania category. And, his father's brother (Pete's uncle) was/is obnoxious and rude to his own mother. So far, not a huge problem in terms of explanation. Obnoxious behavior is not exclusive to this particular family, especially in our culture. However, Pete and his uncle both cannot sleep unless they have locked their bedroom window, even on the hottest nights, because "Manson will come in and kill them." Of course, we learn fears easily and it could be coincidence, but ...
Pete's mother taps her lower knee when her legs are crossed; so does her brother, so does her father.
All of them have difficulty with "noise distractibility" and cannot filter the small repetitive sounds made by other family members.
Ernst Mayr (Evolution and the Diversity of Life, Harvard Univ Press, 1976) talks about "essentialism" and specificity. "Essentialism" characterized the work of continental biologists during the middle 19th century. Like Plato, they sought idealized patterns that were dimly reflected in factual data. England is said to have less of that influence, and to have less fear in discussing the fine particulars of behavior. Thus, Darwin and Wallace, even though outside academia, were able to discuss variation in traits rather than concentrating on their "pure" expressions, free of variation. The theory of evolution by natural selection of random variations was possible because of the possibility to focus on details, rather than ideals.
American psychology, attempting perhaps to emulate physics, also sought principles unsullied by facts, by variability. Variability was calculated into its own precise measures and used to assess differences between groups of observations. If the "signal" was greater than the "noise," then something was happening and science took a step forward. (1)
Familial traits, however, are not of a Platonic nature. Essentialism, statistical averaging, will obscure the events under study. "Temperament" is a relatively global term, describing the central tendency of many smaller units of conduct. If we track the smaller units, then we may find nothing in common across members of the same generation. All commonality will be across generations of the same family. And even that commonality will be diffused by the actions of meiosis, excitable fields, critical life experiences, and the whimsical impact of environment.
The most parsimonious model thus far is to: a) Admit that familial action patterns exist b) Develop a scheme, a set of procedures for recording them across generations. (Again, the SCID format orchestrated by an extensive, computerized algorithm makes the most sense in terms of current technology as well as the time constraints that exist in a typical clinic office.) c) Attempt matching their appearance with varied models for the expression of other genetic traits. d) Explore possible relationships between the highly detailed, familial action patterns, and more diffuse concepts such as Psychological Adaptations. (2)
These things will need some time. Meanwhile, pray-admonish-hope that these concepts are not again used to justify ideological campaigns based on illusory claims of superiority. "Superiority" is environmentally relative, our environment changes from day to day and will likely continue to do so. Thus, there is never an answer to determining "superiority," there is no endpoint possible so long as time and circumstance continue to recast life's dice.
1) This problem emerges every now and then. Clark Hull believed in a physics of behavior, derived averages, and drew curves of "best fit" for variable data. Skinner started with Hull's model (Check the "Behavior of Organisms" in the opening chapters and read Skinner's own behavior formulae that differed little from Hull's!) and rejected it for the study of functional relations between variables, relations of sufficient power to be reflected in the behavior of each individual creature.
2) Guilford once attempted a modular construct of psychological functions. Take his "structure of intellect" model and draw evolutionary connections between the different modules, relabeling many of them. You might get something familiar to more traditional psychologists as well as comfortable with the cognitive and evolutionary scholars.