The North American wood frog Rana sylvatica can survive being frozen solid - no heartbeat, no brain activity. This animal survives the winter in a frozen state. In the Spring, the wood frog thaws out and spontaneously reanimates itself. The wood frog holds the key to organ cryopreservation, understanding how we can rapidly chill people in trauma cases while transporting them to hospital, as well as the key to long-term suspended animation.