Gee’s Reviews > Race And Crime: A Biosocial Analysis > Status Update

Note that r- or K-selected traits are mostly behavioral traits underpinned by physiological processes that help to maintain those traits, thus we are talking about facultative strategies, not genetically fixed ones (Rushton, 1997).

an enzyme called monoamine oxidase A (MAOA). This enzyme acts in the brain to maintain the healthy balance of several different neurotransmitters, including serotonin and dopamine, by breaking them down and recycling the excess. Low levels of MAOA may be insufficient to clear away the "chemical debris" within the synaptic spaces, which will then interfere with subsequent neurotransmissions.