courage. Not surprisingly, social interactions, as configured by the mouse’s own personality style, contributed significantly to their behavioral patterns. As an example, the C57BL strain of laboratory mouse has strong tendencies toward impulsively wild behavior. To be anthropocentric and using Hagen and Eysenck-like behavioral dimensions, we could describe the C57BL mouse as exhibiting high psychotocism, P, energetic sociability, high energy, E, and low emotionality, low neuroticism, N. The C57BL also loves alcohol and will dominate the low E, shy, low P, retiring, alcohol avoidant, high N, emotional, anxious, frequently defecating albino BALB strain of mouse when they are placed together for a limited time in a novel situation during the daylight hours. Over a more extended time, however, the BALB mouse comes to dominate the C57BL, beginning with attacks in the dark and finally as the persistent and patient survivor over days of aggressive fighting. BALB’s low E, social fear eventually turns into rage and aggression. The C57BL is quick to mate and ejaculate but very slow to recover sexually, so that the less post-orgasmically refractory BALB also wins in long term sexual competition in a cage full of fecund females. Modern social psychological approaches to human personality are beginning to approach the interactions of genetic brain proclivities and collective social dynamics in this way. Employing Eysenck categories of personality characteristics, similar results about style as influenced by genetic selection can be seen in humans. The correlations between factor scores based on B. Loehlen’s studies using the California Personality Inventory in twins demonstrated as much as threefold higher correlations among identical twins for extroversion (E) and neuroticism (N) factors compared with matched fraternal twins. The primacy of some of the in-born biological roots of these personality styles is suggested by G. Methany’s finding of higher correlations between iden