rkay, the porcupines I know definitely have longer quills than your hedgehogs. It seems to me that they are related but different. Porcupines, like most creatures confident of their defense, are not irascible but I think are less docile than hedgehogs. They cannot throw their quills. They will, however, strike at a threat with their tails, impaling the victim with nasty barbs which are very painful to get out (as more than one local dog can attest) and leave him looking like he's lost a fight with knitting needles.