The orca's brain processes the information and the orca can then 'see' the image. Orca use echolocation to find out about their surroundings, where prey are and where other members of their pod are. Endangered means very few of a species is remaining and the animal is likely to become extinct if nothing is done to protect it and its habitat. The equator is an imaginary line which divides the world around the middle into the Northern Hemisphere and Southern Hemisphere. It is around the equator that some of the hottest places on earth are found such as the Sahara desert in Africa and the Gobi desert in Asia.
Erosion is the wearing away of a part of a habitat.
Many habitats are being destroyed by erosion, including over-used footpaths eorded by people's feet and the forest soil eroded by wind and rain when trees are cut down, which is happening at an alarming rate in tropical rainforests of South America and Africa. Evaporation occurs when an organism loses water. For example, during the day the sun heats up plant leaves and tiny droplets of water known as 'vapour' are 'evaporated' into the air from the plants. Evolution occurs constantly as habitats continuously change and plants and animals adapt with their habitat. This may occur instantly or slowly over many generations or even millions of years.