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Wild ZebraA population of different species living together is called a community. A lion, a zebra, a hyena and a giraffe living in one area in Kenya is an example. The distribution of living things in an area depends on the abiotic factors or the non-living variables present. Examples of abiotic factors in the savanna include: the amount of sunlight, precipitation and temperature.

All living beings need energy to survive. Plants are primary producers, they convert the energy from sunlight into glucose by a process called photosynthesis. Consumers depend on other organisms for their energy. Decomposers break down dead bodies into nutrients which can return into the soil. In the savanna, a zebra eats grass. The zebra is then eaten by a lion. The lion is attacked by another lion and dies. Worms will decompose the lion's body. This simple relationship is called a food chain.

In an ecosystem, relationships are more complicated than one species eating another. Somtimes, an organism called a parasite will live on or in a host organism and derive their food from the host, without killing it outright. This is called parasitism. For example, a tick living on an elephant will drink the elephant's blood without killing the elephant. Other times, species will live together in a relationship called symbiosis. Mutualism is a type of symbiosis that is beneficial for both partners. For example, a bird will eat the ticks on an elephant. The elephant gets rid of the ticks and the bird gets an easy meal. Commensalism is a type of symbiosis where one partner benefits without significantly affecting the other. For example, a plant seed will hook itself onto the fur of a lion and will land somewhere else. This aids in its dispersal but does not benefit the lion.