In the comments below Nathaniel Comfort asks:
What I do, as a historian, is take something apparently simple and make it more complicated. I wonder about how your curves, e.g., would be applied in real life. *Specific* couples, *particular* children–individuals, cases, persons, context.
I’m asking things like:
-What would your hypothetical psychopathic lovebirds do with that information?
Comfort is referring to this figure I generated, which shows the potential distribution of outcomes for two individuals who tend toward more psychopathy than the general population. It seems to me that this question is easily answered if simply replace “psychopathy” with “odds for heart disease.” Endophenotypes aren’t magical, they’re just sometimes hard to characterize. But once you get a good grip on them you can make standard quantitative genetic predictions. One of the points I wasn’t clear about in the chart is that I assume that the “trait” being measured is the tendency toward psychopathy as measured by a paper & pencil test in one’s youth. This does not entail that an individual in fact behaves like a psychopath. Rather, it simply implies that they’re odds of behaving like a psychopath as an adult …