An ecological zone whose uniformity is defined by the type of plant life that dominates within it, since plant life will often give a strong indication of other ecological features of a zone, such as animal life and soil type. Because biomes are defined by plant life rather than region, some biomes can stretch around the world. For example, the Boreal Forest biome (defined by the predominance of conifers) covers much of northern Europe, Russia, and Canada (Woodward, no date, Env. Literacy Council). Other major biomes are: tundra, temperate (deciduous) forest, tropical rain forest (selva), tropical grassland (savanna), temperate grassland (steppe), and hot deserts. A biome is an idealized type; local variations within a biome are sometimes more significant than variations between biomes.