Levels of organisation

Ecosystems and material cycles · Communities and interdependence · note 1 of 4

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Levels of organisationSpec 9.1

Living things can be described at different levels of organisation, from a single organism up to a whole ecosystem. Each level contains the one before it.

Levels of organisation in ecology
Level	What it means	Example
Organism	A single living thing	One badger
Population	All the organisms of one species living in the same area	All the badgers in a wood
Community	All the populations of different species living in the same area	The badgers, foxes, oak trees, insects and fungi in the wood
Ecosystem	A community together with the non-living (abiotic) parts of its environment	The wood, including its soil, water, light and temperature

An ecosystem is made of living (biotic) and non-living (abiotic) parts that interact with each other. Energy and materials move between them.

Nested boxes showing the levels of organisation in a wood: one badger (organism) inside all the badgers (population), inside the community with an oak tree, fungi and an insect, inside the ecosystem with light, temperature, water and soil. — Each level contains the one before it: **organism**, **population**, **community**, then **ecosystem** (the community plus its abiotic parts).