Humans are mammals. The word mammal comes from the Latin mamma, meaning breast, because female mammals produce milk to nurse their babies. Nearly all mammals give birth to live young, and all are warm-blooded, maintaining a near-constant body temperature regardless of environmental conditions. They are vertebrates and use lungs to breathe air and are the only animals that grow hair. Mammals probably appeared on Earth some 200 million years ago.
See the World's Megafishes A diver shares a tank with an adult arapaima fish at an aquarium in Manaus, Brazil. Known as the pirarucu in Brazil and the paiche in Peru, this South America giant is one of the largest freshwater fish in the world. more»
African Elephant African elephants are the largest land animals on Earth. They are slightly larger than their Asian cousins and can be identified by their larger ears that look somewhat like the continent of Africa. more»
Tornadoes Tornadoes are vertical funnels of rapidly spinning air. Their winds may top 250 miles (400 kilometers) an hour and can clear-cut a pathway a mile (1.6 kilometers) wide and 50 miles (80 kilometers) long. more»