All living and non-living things (biotic element )in a given area that interact with one other, make up an ecosystem. The non-living part of an ecosystem includes water, rocks, air, light, and soil. All the different organisms that live together in an ecosystem is called a community. Each ecosystem has its own community. A terrarium community, for example, can have small animals. A desert community may have cacti, small snakes, and scorpions. A pond community can have frogs, insects, snakes, and plants, and a forest community may have rabbits, foxes and pine trees. Communities are also divided into populations. A population is composed of only one type of species. A species is a group of similar organisms; for instance, all humans belong to the same species.
A community works like a team. Each member of the team has its own job to do but they are all interconnected. For example, in a forest community there are different populations, such as grass, rabbits, and foxes. The rabbits eat the grass. The foxes eat the rabbits. If there were no foxes, the rabbit population would grow too quickly and there wouldn't be enough grass for all of the rabbits to eat. Then the rabbits would begin to die, and the foxes would soon die because there is nothing but grass too eat. Predators and their prey are in every community. They help to keep it balanced so that all the members can survive. Three types of team members in a community help establish balance: the Producers, the Consumers, and the Decomposers.