An earthquake decimates a ground-squirrel population, killing 98 percent of the squirrels. the surviving population happens to have broader stripes, on average, than the initial population. if broadness of stripes is genetically determined, what effect has the ground-squirrel population experienced during the earthquake?

Which of the following  bestillustrates a negative reinforcer?               a.  copland gives up candy to stave off chronic acid indigestion.    b.  nancy learns that she prefers chocolate over vanilla.    c.  carmine changes his major to english lit after failing a math exam.    d.  on a hot day, lindberg always drinks lemonade.