social hierarchy
ddobbs | April 8, 2009More or less alongside my piece on depression's wiring diagram, this months' Scientific American Mind has a piece I wrote on how social hierarchies develop among rats.
Darlene Francis, a psychologist at the University of California, Berkeley, placed 80 newly weaned rats in cages of four, with cage mates matched for size, activity level and early life environment. To Francis's amazement, it took weeks--until the rats were well past puberty--for a social hierarchy to evolve (as indicated by which mouse got first dibs at food and water, among other measures). Perhaps more surprising was that…