The animal kingdom: how animals are classified -- Animal species: how many different kinds of animals are there? -- Size: from the small to the gigantic -- Biomass: how much do all the termites in the world weigh? -- More biomass: the world's heavyweight champions -- Speed: what are the fastest animals? -- Animal leapers: jump! -- Wingbeats: staying airborne -- Sleep: how many hours a night? -- Life spans: from one day to 500 years -- Heart rate: fast and slow -- Horns: different shapes and sizes, all with a sharp point -- Tongues: for reaching-or catching-a meal -- Animal sounds: loud and louder -- Defenses: how an armadillo stays safe -- Poisonous or venomous?: the most toxic animals in the world -- Deadly animals: human deaths caused by animals -- Deadlier: the most dangerous of all -- High land low: living on a mountain top or deep in the sea -- Hot and cold: surviving in extremes -- Migration: animal journeys -- Mass extinctions: life's greatest disasters -- Endangered animals: almost gone.