Doves and ducks and dragonflies. Ferns and worms and Arctic terns. Bears and beetles, tigers and frogs—they’re all part of the bountiful variety of life on Earth. This bounty of life is often called “biodiversity,” which is short for “biological diversity.” Today the biodiversity of many of Earth’s regions is in decline. Conservation is crucial to protecting biodiversity and to ensuring that plants and animals and other living things—and the places they live—will be here tomorrow and for future generations. Visit the Critical Mass: A Biodiversity Atlas of the U.S. and Canada Web site. Then click below for activities that help us take stock of life on Earth and explore the relationship between biodiversity and conservation.