1001 Space Earth Nature Evolution Fossils and Prehistoric Life Dinosaurs Simple Animals Insects and Spiders Fish Amphibians Reptiles Birds Sea Mammals Land Mammals Plant Kingdom How Plants Live Unusual Plants Ecology Conservation Animal Behaviour Pets and Farm Animals History Human World Science and Technology	What is a species? Both plants and animals are classified, or grouped, into species. Members of a species usually look very similar to one another. An animal or plant of any particular species can only reproduce successfully with other members of the same species. A selection of mice   Previous: Back Book: 1001 Section: Nature Chapter: Ecology