The fundamental concept of ecology is that living organisms interact with and are dependent on their environment and each other. These interactions results in a flow of energy and a cycling of materials that are essential for life.
Competition can occur between members of different species for an ecological niche. Competition can also occur within species. Competition may be for abiotic resources, such as space, water, air, and shelter, and for biotic resources such as food and mates. Students should be familiar with the concept of food chains and webs.