As much as we may like to believe that mother animals are designed to nurture and protect their young, to fight to the death, if need be, to keep their offspring alive, in fact, nature abounds with mothers that defy the standard maternal script in a raft of macabre ways. There are mothers that zestily eat their young and mothers that drink their young's blood. Mothers that pit one young against the other in a fight to the death and mothers that raise one set of their babies on the flesh of their siblings. Among several mammals, including lions, mice,...