What is a Biome? The major terrestrial ecosystems are classified into units called biomes A biome is a large region characterized by certain conditions, including a range of climate, precipitation, and plants and animals that have adapted to those conditions. Every place on earth is part of one biome or another.

Driest biome on Earth Precipitation: less then 25 cm a year –When it does rain it evaporates rapidly, so the soil retains very little moisture –Because there is little water, plants are spread widely apart and the ground is mostly bare Few large animals are found because there is not enough food or water to support them.

The desert supports little plant life Plant adaptations: –Cactus plants, spiny leaves, large, shallow roots that quickly absorb water Animals and adaptations: –Owl, iguanas, fox, lizards –Kangaroo rat Never need to drink water; they get moisture from the food they eat They are only active in the early morning or late afternoon when the temperatures are less extreme

Precipitation: 200 cm to 225 cm each year Temperatures are warm and stable Tropical rain forests are lush, productive ecosystems containing more then half of all the species that exist on Earth. Plants: – Over 700 species of trees –Over 1,000 species of flowering plants

Plants: Vines, orchids, moss, ferns Adaptations: orchids grow on trees to get more sun light - many plants have large leaves to catch more sunlight Animals –150 different types of butterflies –Snakes, Lizards, Salamanders, Monkeys, Bats, Jaguars –Birds: toucans, cockatoos, hummingbirds

Found in northern and southern hemispheres Regions usually have 4 seasons a year Precipitation: 75 cm to 150 cm yearly When the weather gets colder and trees lose their leaves some animals migrate to warmer regions –Other animals hibernate

Plants –Coniferous trees ( pines) – Deciduous trees (oak, maple, hickory) Animals –Raccoon, Bald eagle, White tail deer, Red Fox

There are grasslands on almost ever continent Precipitation: 25 cm to 75 cm yearly –They have a dry season with little to no rain –This prevents larger plant from growing here Main plant is grass

Plants: Grass such as: – Wheat, Oats, Barley, Corn –Grasses have extensive root systems that can absorb water when it rains and can withstand drought during long dry spells Animals –Kangaroos, Wildebeests, Zebras, Prairie Dogs They eat the stems, leaves, and seeds of grass plants

Is located near the north pole Cold, dry, treeless region and is covered with ice most of the year Winters are 6 to 9 months long Precipitation ~ less then 25cm a year

Plants: – lichens (reindeer moss), True mosses, Grasses, Small shrubs Animals - in the summer –Mosquitoes – Birds (Geese, ducks, snowy owls) –Mice, voles, lemmings, artic hares, caribou, musk oxen

Which biome gets the least amount of precipitation? What is the difference between a ecosystem and a biome?