Hedgehogs possess a natural resistance to many toxins allowing them to eat creatures with chemical defenses like wasps and bees, even venomous snakes. The hedgehog is up to forty-five times as resistant to viper venom as a comparably sized guinea pig. It requires one tenth of a gram of cantharidin to kill one hedgehog. This amount, however, will kill up to twenty humans. They may also survive extended periods without food or water.
Hedgehogs live predominantly solitary lives.
Young are born in litters of one to six after a 40 day gestation. Young are born with soft spines under a protective film. Spines harden soon after birth. St. Tiggywinkles Dr. David Macdonald's Encyclopedia of Mammals is one of the great standards for mammal information including the hedgehogs. Although the photos are mixed quality black and white, this two volume set has great text.