The ecosystem refers to all the biological communities as well as the nonliving abiotic components-soil, light, air, water, etc. in a given area. Ecosystems are part of the biosphere--places on Earth where life exists. The organisms living in a particular ecosystem are adapted to the conditions that exist there and due to natural selection, the best adapted are deemed fit and pass their traits along to the next generation. If global warming occurs, climates will change. Places that were once temperate or even cold may become warmer and the organisms adapted to the previous conditions may become endangered or even extinct. Other organisms may find their habitats have expanded. For instance, Anopheles mosquitoes that transmit malaria may have new habitats to exploit when the planet becomes warmer. Coastal areas will become flooded due to rising sea levels, as the polar ice caps melt. Organisms such as the polar bear, which is adapted to the conditions of the Arctic tundra will lose habitat as the polar ice becomes scarce. Global warming will affect all components of Planet Earth both biotic and abiotic.